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The brain as interconnected boxes: autonomy, distributed signals, and an "I-function"

Paul Grobstein's picture

Welcome to the on-line forum associated with the Biology 202 at Bryn Mawr College. Its a way to keep conversations going between course meetings, and to do so in a way that makes our conversations available to other who may in turn have interesting thoughts to contribute to them. You're welcome to post here any thoughts that have arisen during the course this week (and to respond to thoughts others have posted).

Some issues worth thinking about this week is thinking about the nervous system in terms of interconnected boxes that can generate signals on their own, input and output as distributed signals, and the existence of an "I-function". Are these good summaries of observations? stories? What observations do they not incorporate? What new questions do they raise?

jwong's picture

This whole discussion

This whole discussion regarding the I-function and the idea of a “self” inside of us has been really interesting to read about. It reminds me of a Law & Order: SVU episode that I watched about this teenage boy who reportedly could not control his sexual inclination due to some increased levels of --- in his brain. When asked whether or not he had a sense of himself or a sense of right and wrong while he was infringing on the law, the teenage boy responded that he knew what he was doing the whole time—he just could not control himself. This convoluted storyline kind of got me thinking about that idea of “self-awareness” and people who break the law. Having poor “executive functions” in the brain, meaning an impairment in controlling one’s actions, planning, or abstract reasoning, are symptoms of aggressive boys, according to an article I found online ( Researchers noted that aggressive behavior has been linked to hyperactivity in the brain and that reasons behind such behavior might only be answerable by some unknown neuroanatomical chemical or physiological handicap.


Going back to the point of this entry… I think inputs and outputs occur with reason, whether or not the final outcome seems reasonable at all to others but the person performing the action. Perception itself is an action that is a response to social standards, and thus can be seen as a result of conditioning of the brain to specific inputs to produce specific outputs. Also, the presence of the “I-function” can be seen to have been present in the boy’s psyche. Even though his actions were seen as illegal and violently wrong, he was aware of his conduct the whole time, and thus could be said to have been aware of himself, of his ability to reason. With this ability, one would wonder why he would willingly continue to perform such heinous criminal actions; if he was aware of himself and of his ability to stop what he was doing, what prevented him from actually going ahead and doing so? The episode concludes with the explanation simply that his inability to stop himself or react to his own self is something that relates back to the I-function and some chemical imbalance in his brain. I thought it was interesting to see how such a radical pattern of activity could be related to a person’s sense of self and awareness (in terms of morality and being capable of determining right and wrong). How strange to think that a few missed relayed inputs/outputs in the brain can cause such detrimental behavior in a fellow human being.

heather's picture

a site, and a thought

so here is a site that i stumbled upon:
many links related to reptile brain research.
maybe a few will bear fruit worthy of contemplation for some of you... i'll hold off on my reactions for the moment for there are too many of them to choose between.

one thing though:

i think it's important to state that we should not confuse our lack of knowledge about non-mammalian neurological function with non-mammalian neurological inferiority.

we have a lot to learn.

Lyndsey C's picture

alpaca farm girl

After class I went back and looked at the action potential propogation simulation and i am still trying to figure out why there are a series of action potentials being carried out during movement instead of just one message being passed along the axon. Then I realized maybe each movement is enabled by a series of action potentials, one after the other, resulting in a fluid movement. (ok, i didnt exactly come to this epiphany, i got some guidance from a really smart friend who actually took this course last year). but now i am confused about why the action potentials are triggered in both directions of the axon in the action potential propogation excercise when you begin an electode in the middle of the axon. i was under the impression that messages are only carried in one direction on a nerve cell (down the axon). and then i got to thinking about reuptake processes, and how neurotransmitters are sometimes reupaken (word?) into the neuron for storage or reuse. is that what the excercise is trying to illustrate? if not, why are the action potentials going in both directions of the axon? and why would you begin an electrode in the middle of an axon in the first place? that sort of goes back to the idea of having output with no input because the typical starting point of the first action potential is usually at the top of the axon. right? i am really confused, and this might sound very trivial to people who have a more advanced background in neuroscience, but if anyone can make this a little clearer id really appreciate it! see ya'll thursday!
K. Smythe's picture

Who has a sense of self?


Much of the science i've been taught in my high school and college years is in essence reductionist theory.  We give lip service to the idea that other animals may have "at least some concept" of self, that the "mind" or "soul" exists outside of the physical nervous system and then we quickly dismiss these ideas or at least let them take second place to theories that are easier to support.  Off of what EB Ver Hoeve was saying our observations of animals are really just that-external observations.  Some of the things that we do, in all of our glorious consciousness, would probably be hard to prove as the workings of the neocortex if we did not have the subjective view that we do.  Unfortunately it seems as if all of our observations of other creatures will have to be from outside their minds unless we find a better means of cross species communication.  It is tough for me to believe that as humans, we are the only animals with a sense of self when my only evidence/observations toward this end are a lack thereof.  I could just as easily attribute my observations to naïveté on my part as to the internal workings of an animals "mind".  A cute quote from Douglas Adams that sort of has to do with this (okay, so mostly i like it and want to share it with you all):

"Man had always assumed that he was more intelligent than dolphins because he had achieved so much... the wheel, New York, wars, and so on, whilst all the dolphins had ever done was muck about in the water having a good time. But conversely the dolphins believed themselves to be more intelligent than man for precisely the same reasons."


MarieSager's picture

I think the "smooth eye"

I think the "smooth eye" experiment we did in class on Thursday was REALLY cool. The idea that we are only A PART of our nervous system both intrigues me and freaks me out. I feel like there is some kind of alien/machine inside of me...and I've always thought that everything in my body/everything my body did and achieved was ME, but this experiment raises new doubts and avenues for exploration....
evanstiegel's picture

The new incorporation of

The new incorporation of an I-function in our brain model was a signficantly more less wrong model than our last.  This model accounts for the self-recognizing property that we humans have.  However, a problem that is still not accounted for is what differentiates that I-function input-output boxes from other boxes.   Perhaps it is located in the neocortex, a part of the brain that makes us and other mammals unique.  But is that suggesting that organisms that lack a neocortex lack an I-function box? It is difficult for me to believe that some organisms lack I-function.  Maybe, my inability to believe is attributed to the fact that I possess a neocortex which prohibits me from accepting that some organisms are simply more primitive than I am.

EB Ver Hoeve's picture

Hold up!


Last week, we were introduced to several new observations. One of those observations was that the neocortex was found only in mammals and in no other animals. We were shown a picture of our brain (with the identified neocortex) and then we were shown the frog brain (missing a recognizable neocortex). After being shown these observations we were asked, what is the behavioral difference between mammals and all other animals? To that, we have had many responses in the forum. Some are revealing that we are having difficulty finding behaviors that are entirely unique to mammals. However others, many others, have jumped on board behind the wiki definition of neocortex stating that the neocortex, “is involved in higher functions such as sensory perception, generation of motor commands, spatial reasoning, conscious thought and, language” and that therefore, it is these behaviors that separate mammals from all other animals. This is where the problem begins.

Just because the difference between mammals and all other animals appears to be in the existence of the neocortex, this should not imply that mammals (exclusively) are “capable of higher functions such as sensory perception, generation of motor commands, spatial reasoning, conscious thought and, language” and that all other animals are not. Let’s think carefully about what observations/behaviors we are looking at to come to this conclusion.

Perhaps this analogy has been carried too far. Perhaps we humans are being too self complimentary. Frogs do pretty well for themselves. They perform some if not most of the said neocortex behaviors. Reptiles may not have a distinctive 6-layer neocortical structure, but so what? That should not necessarily imply that they are not capable of performing complex behaviors. They could, for example, be performing complex behaviors in different areas of their brains. I guess what I am saying is that just because we have a neocortex and we have higher order thinking, we should not imply that the neocortex is the only structure capable of thinking.

I read an article in the science times about a bird (a godwit) that flew non-stop for 8 days from Alaska to New Zealand. Scientists are trying to study the brain to see how that can be possible. I guess I think there is just a lot more we have to learn before making too definitive cross mammal comparisons.

(see :

heather's picture


thank you for articulating this argument so well.
Penn Tong's picture


It's interesting that currently, only mammals have neocortex's, but have scientists made any discoveries about dinosaurs having a neocortex?

Skye Harmony's picture

what is consciousness?

I left class wondering if we are going to talk about definitions of consciousness in class this week. It seems that humans have been questioning consciousness for centuries and yet we don't quite know what it is.

I read the article posted by Jessica Varney above. It addressed one of the things I have been thinking about: theory of mind and how it relates to consciousness. Cheney and Seyfarth, two researchers mentioned in the article, came to Haverford last semester and gave lectures on primate brain and behavior. They said primatologists still haven't come to a conclusion as to whether nonhuman primates demonstrate theory of mind, attributing mental states to others. One researcher in the article thinks that upbringing by humans influences awareness, so so-called feral children might not have the same "consciousness" we do, and nonhuman primates raised by humans might have a more similar version of awareness to humans than their relatives raised in the wild. It seems that there have been conflicting observations on both the issues of self-awareness and theory of mind in nonhuman primates; I wonder if one can exist without the other, and if both are necessary for what we call consciousness.

I watched a show a while ago about a phenomenon that sometimes occurs during surgery in which people are conscious, so they are completely aware and can feel everything, though they can't move because of the paralyzer given to them. Medical researchers are trying to develop more sophisticated measurement devices so that surgeons can detect when patients could still be conscious and adjust their anesthetic accordingly. I find this fascinating. First of all, it's interesting that some of the cables between brain and body can be active while others aren't; nocireceptors still send pain messages to the brain, though the brain can't send messages to motor neurons. Second, it's amazing that we have such advanced surgical techniques that allow us to fix problems even in the brain, but we still can't reliably measure consciousness.

gflaherty's picture

pain, reflexes, paraplegia

I thought a lot about the end of our discussion on Thursday and the mention of pain.  I decided to do some research on the subject after it was suggested that pain is only experienced in the brain.  I found some interesting results that seem to reveal more about the already complex nervous system that has been laid before us this semester.   Upon the discovery of the nociceptor, a specialized sensory receptor that is only activated by painful stimuli, I realized that pain is much more complex a sensation than I had originally thought at the end of class.

One of many specialized sensory receptors, like photoreceptors or olfactory receptors, nociceptors relay information to the brain.  In this case, the information is relayed in order for the brain to seek cessation of the stimulus causing the activation of the nociceptors.

Although this sounds extremely simple and straight forward, I began to think about reflexes.  A reflex is an involuntary action.  This could be anything from the blinking of the eye when the sun is bright to rapidly removing a hand from a hot surface. To me, these actions are incredibly interesting because they are done without the use of the brain. Signals from the sensory neurons are sent only to the spinal cord, which relays information back to the motor neurons that signal an action to occur.  This pathway, known as the reflex arc, allows for minimal damage of the body by responding in the quickest possible manner.  I just thought this was worth mentioning given our discussion of paraplegia on Thursday.  I read some sources that mentioned thatthis same type of reflex arc is employed by paraplegic patients as well.

Anna G.'s picture

pain class

If your interested more about pain, I took a realy cool class at Haverford last semester called The Psychology of Pain and Pain Inhibition that I would really suggest. It goes into depth about pain from nociceptors to how it's processed in the brain, and the malfunctions that occur.

cheffernan's picture

Sexual Dimorphism in Brain Structure

A concept looked at in class on Thursday was the idea of variation among brains within a species. As stated in class in accordance with Emily Dickinson’s poem concerning the brain, since people behave differently, people have different brains. This idea was explored more in class when we considered the brains of songbirds; male songbirds act differently as they are the sex that actually sings the song, while female songbirds determine if the song is worthy of a response. Based on Dickinson conclusions we have been making, we would conclude that the male birds would have different brain construction than female birds, which when we looked closer was the truth. But the question is: can these differences in brain formation be seen in humans?

While there are differences that exist between men and women, few behaviors are strictly male or strictly female. One noteable difference between men and women is that women are more associative in thought than men, but can it be stated that this difference in behavior is because of biology or because of different styles of raising boys and girls? It turns out that female brain have a larger corpus callosum, which connects the two halves of the brain, and contributes to the fact that women are more associative in nature than men.

Therefore it can be seen that the sexual dimorphic brain seen in the songbirds has been maintained as it is exhibited in humans as well. Therefore it can be assumed that all species have some degree of sexual dimorphism in brain structure.
Skye Harmony's picture

Re: sexual dimorphism

Just because we have observed it in two species does not mean we can assume it occurs in all species! (Though it certainly is possible that all species do exhibit some brain differences based on sex.)

Madina G.'s picture

Not the perfect model...

The notion of the "I-function" is an intriguing concept, however it still does not summarize completely observations of how the nervous system functions. Thinking about the nervous system in this manner, as a mechanism of input and output boxes sometimes capable of generating outputs without the presence of inputs, and furthermore containing an "I-function" that is responsible for what we are able to recognize as something happening to us, again brings to mind Phantom Limb Syndrome. Here is a situation in which there is no input of pain, yet there are mere "nonsense" responses that are processed in the brain and interpreted as pain in a limb that is no longer present. The patient claims that they feel the pain in that limb, an affirmation of their ability to sense the "self" or in other words the "I-function", even though there is nothing there to feel.

Is this a glitch in the I-function model? Or does the I-function strictly apply to nervous system disorders, and can only explain the loss of feeling of the self when a particular area of the spinal cord is injured? How about patients who undergo amputation and do not experience any form of PLS, rather it is understood that the limb is no longer present and therefore they can not feel anything in that region? Is this also not a loss of the "I-function" without any damage done to the spinal cord resulting in paralysis?   

Anna G.'s picture

phantom limb pain's relationship with the i-function

I think the issue here is less the fact that the model is wrong, and more that it just doesn't go into enough detail....which is understandable considering the mechanisms behind phantom limbs and phantom limb pain is not completely understood.


When there is pain sensation from a limb that is no longer there, it is due to the fact that the nociceptors and the synapses that carry their signals to the brain have had an afferent barrage (usually) and the functioning of the sensory nerves and their pathways have so messed up that there is continual abnormal firing, resulting in pain. This is why when patients have a limb amputated in the hospital they give a nerve block and use anesthetic, as well as why there is evidence that shows patients who had no pain in limbs before they were amputated do not usually have phantom limb pain, but people who had horrible pain in their limb (ie the reason why it had to be amputated) did. [Also if your wondering how they got data on people who didn't have pain in limbs that were amputated, it was from an area in Africa where healthy people were dragged from their houses at night and their limbs were cut off by another group.]


Phantom limb pain is an issue that deals with the spinal cord and the associated nerves, which is why I don’t think it’s an error in the model, but merely details an area where more detail is needed. However, this detail is needed not only in the model, but in real life as well, since the mechanism underlying this problem is not well understood.


 In fact, I think the model does a rather nice job of summarizing the observations we have on phantom limb pain. We have shown now that input can affect boxes, which can then modify/amplify/etc the signal and send it to the brain. These inner boxes obviously have a malfunction, and continually send information that is not accounted for by the input, something out new model allows us to show.


Jessica Krueger's picture

On a completely different note...


While I do find my peers' posts fascinating, all this talk of neo-cortex has left something a bit wanting - without all that "useless" white matter, cells in various regions of the neo-cortex couldn't even hope to talk to each other. Those globs of white matter are the axons of somas in the neo-cortex, their white color springing from the fatty sheath of myelin which allow electrical signals to travel faster along the nodes of Ranvier rather than measly simple conduction.

While CAT scans, MRIs and, more recently, fMRIs have begun to illuminate the space between our ears, not much could be said of the white-jumble between various processing centers thought to be responsible for various. Thought about how the brain worked leaned towards localizing processes to specific regions of the brain, and the methods of neuroimaging available to researchers at the time supported such hypotheses by providing data on the grey matter structures of the brain. This, however, only told half the story, as can be seen by a more recent move away from localization theories after the incredible plasticity of the brain came to light.

Enter diffusion tensor imaging, a form of neuroimaging I find so freaking cool that I actually mention it on a dating website profile. By measuring the movement of water molecules across tissues, the tracks of myelinated axons can be traced and the connectedness of structures in the brain observed. The applications of this new imaging technique are only now being realized; from tracking plaque development in multiple sclerosis to observing abnormal connections in the brains of schizophrenics.

My absolute favorite application of DTI has been in the study of the underlying physiology of synesthia. Two warring camps attempting to explain this abnormal union of sensation developed over the years: one arguing that it was due to poor feedback inhibition which allowed activation to spill backwards to other “associated” areas, the other arguing that synesthesia resulted from a higher degree of connectivity in the brains of synesthetes presumably from a failure in the first cell apoptosis in infants. By comparing connectivity in normal humans and color-grapheme synesthetes, Romke Rouw and Steven Sholte were able to show that at the very least synesthetes DO show a higher degree of connectivity in their brains. Another influential researcher in synesthia, Dr. Cytowic, argues that synesthesia is an inherently “mammalian” state and that humans are alone in not experiencing their worlds in a synesthetic sense. He cites some very difficult to understand studies which show that neonates seem to experience their world synesthetically, a trait which disappears as the child develops.

Interesting Reads:

Increased structural connectivity in grapheme-color synesthesia.

Diffusion Tensor Imaging


Cytowic’s Website on Synesthesia



Jessica Varney's picture

Primate consciousness

Sophie F's posting lead me into an interesting journey through the winding information mines of the Internet, as I wondered to myself, "Is consciousness a uniquely human trait?" Looking to the example of non-human primates, my gut instinct was "no, but I wonder what aspects of consciousness are?"

The mirror test, developed in the 1970s, was designed to test whether chimpanzees had self-awareness. The test involves placing a mark on the forehead of the subject, then placing them in front of the mirror and seeing how the organism reacts. Very young children (and I will tell you anecdotally that this is true of my stupid, 20-lb kitten, too), when placed in front of a mirror, will react as though they are seeing another child, but children who are around 18 months old will see the mark and try to wipe it off, which suggests that they are capable of recognizing the image in the mirror as themselves. Humans, great apes (excluding gorillas), dolphins, and elephants have all been documented as recognizing their reflections.
Critics claim that the test doesn't prove an animal is actually conscious of itself, but merely capable of modeling its environment.

I'm interested in further exploring what other tests for consciousness have been done with non-human primates, given that we know that primates are capable of solving problems, modeling body language, and even communicating with humans through sign language and flash cards.
If you're interested in reading more about the mirror test, this webpage has some information, along with really cute pictures of chimpanzees. There's also a really old article about tests of primate consciousness in Science Magazine.
anonstudent01's picture


Like Margaux and many others I am having a hard time grasping how the organ inside my skull can operate independently of anyting my body experiences. Don't any of the principles of causality apply to the brain- don't you need some sort of input to get an output? The environment contained within the brain may never be fully understood but it is still difficult for me to accept that the big box and all of its little boxes really don't need me- even though they are largely what make me me. During class I had a thought that hasn't left me all weekend. Once in a while it seems like my daily experiences are occuring without me present, like I am observing a conversation that I'm engaged in from outside of myself or detatched from "I." Could this awareness/ experience be only the result of too little sleep or rather my thoughts and actions (and everything that makes up the I) functioning without the recognition or real use of inputs but instead as an independent entity? This gets back dualism, consciousness/ unconsciousness and my own puzzlement.
Sophie F's picture


If there is a dualism or co-existence between the conscious and unconscious, can they ever be at odds (not merely in the Freudian sense)? How might this manifest? What is the genesis?
Rica Dela Cruz's picture

I really like the idea of

I really like the idea of having an "I-function" within our brain. It provides people with awareness and a sense of self. The fact that Christopher Reeves could not feel the pain in his leg and feel his leg move shows he has a sense of self because he was unaware of himself moving his leg. Even though "he" cannot move, "he" still has thoughts and is aware of those thoughts. I feel that the "I-function" is the most important part of the brain and without it, there would be no point in living because it gives us who we are. Even if we are still able to act without the existence of the "I-function", how is it worth living when we are not aware or conscious of what we are doing? It would be as if we were robots. 

I think the problem with this "I-function" is that only the individual is able to know if it is still functioning or not. No one else is able to know if another person is aware if no action is produced to communicate that they are conscious. It makes me think about people in vegetated states and why there is this debate about whether people are conscious or not when they are in this state. 

 I think that the movie "The Diving Bell and the Butterfly" provides a great example of the "I-function" in the way it was filmed. (It was really good and everyone should see it.) The way it was shot was that the audience is able to look through the eyes of the character who was paralyzed from head to toe. We, the audience, are able to hear his thoughts and experience his consciousness. This showed me that an "I-function" does exist and even though the character was not connected to the rest of his body, he could still exist. 


maggie_simon's picture

Is the I-function only the concious mind?

I would argue that even with the “I-function” it is still possible to be unaware or unconscious of certain things that we do or think.  These are, after all, related to the unconsciousness that Sophie F reflects on below.  How does the “I-function” account for unconscious processes of the mind?  Are there more input/output boxes within the “I-function”?  Or perhaps, the “I-function” is an input/output box within the unconscious mind.  (Basically the question is whether the mind is more unconscious or more conscious.)

Sophie F's picture

"I", humans, and other jumbled thoughts...

Though not intuitive for me, it makes sense that the “I-Function” is itself a box within a box connected to other boxes… Perhaps it is humans’ ability to define and recognize self, as others have mentioned, that separates us from other mammals.

I am interested in the brains of children who are raised isolated from human contact, whether neglected or “reared” amongst wild animals, so-called feral children ( ). While there is a range of effects the lack of connectedness and stimulation from other humans is the unifying factor. There has been some discussion in the previous posts as to what behaviors define humans, therefore might lead to a larger neocortex than other mammals. My question is, if the neocortex does play a role in higher-order thinking and the ability to define “I” vis-à-vis other humans, how does being raised without group interactions alter or shape the notion of “I” and what is the role of the neocortex? What happens under conditions of sensory deprivation? Do boxes degrade or atrophy if not utilized? Are we hard-wired to survive such conditions or is there no “self-preservation” of the “I-Function” itself? And, if behavior is a pattern of coordinated activity across many outputs, if those patterns are not exercised and very few patterns are produced, does one lose or never actually gain the ability to create these patterns (as specific to children raised in isolation)? Is the Physical Contiguity Principle a series of inherited connections or an infinite set of potential connections within the nervous system?

Behaviorally, many animals do exhibit traits that we tend to ascribe only to humans. Is it anthropomorphizing to draw attention to the many traits other mammals exhibit that suggest a subtlety of “feeling” not simply explained by evolutionary advantage and instinct? For example, elephants, in particular, have been studied in great depth and appear to form very closely-knit social groups and even seem to express what we would call “grief” (The book When Elephants Weep by Jeffery Moussaieff Masson and Susan McCarthy discusses this and other such phenomenon). So, if elephants do, indeed “grieve” for their kin, and have a strong sense of bonding that cannot be explained by evolutionary advantage and instinct alone, the neo-cortices of humans must yet contain even greater subtlety? However, how can we know for certain that our explanation for the behavior of the elephants truly stems from the way in which the “boxes” of these great mammals are arranged? And as Angel pointed out, the ability to “feel” does not necessarily translate into the understanding of the complex web of socio-cultural and neuronal underpinnings that shaped such feeling…

If the “self” is a box within the nervous system, the dualism of conscious and unconscious seem less murky. In schizophrenia, are there two (or more) boxes vying for the “I-Function” or is there a neurochemical input that alters the output?
Zoe Fuller-Young's picture


Wow! I like the thoughts and questions raised in this post. The issues you raised about "feral children" is extremely interesting to me, but on a somewhat different branch. We are talking about the neocortex and humans vs. mammals/other animals, but what about between humans. Reared in different cultures and with vastly different traditions, are the brains of humans, particularly their neocortexes, different? Communication between humans and animals and communication between humans from very different worlds is not so dissimilar. It seems to me that "I-function" patterns are highly advanced in humans, but that even two different advanced patterns are difficult to fuse together.

I agree with many comments above that the neocortex contains a special component in humans expressed in language. Communication for humans, although I mentioned above that between humans it is not always easy, all humans use some sort of language to communicate to each other. I also think that other animals have ways of communicating and it is often through sophisticated strategies, but the similarity between human languages and body language is intriguing and worth noting.

Sophie's question about Schizophrenia makes me wonder if my question before about schizophrenia being a mistake, should instead be are schizophrenic brains more advanced, but somehow unable to cope with "normal" brain communication? Can we survive if there are competing "I-functions" within the same "I"?

Tara Raju's picture

Neocortex and "I-Function", etc.

There were so many things that were addressed in the forum so far- it’s a bit overwhelming so first I am going to address the neocortex and then the “I-Function”. To back track a bit to Jean’s post about the actual function of the neocortex, of course, it seems that there is no way to actually determine all of the functions that it can do but, I did ask my best friend, Wikipedia, about it and it says that the neocortex is “involved in higher functions such as sensory perception, generation of motor commands, spatial reasoning, conscious thought and in humans, language”. Utilizing that general definition of the neocortex, it seems that the function of the area of the brain essentially defines us as an individual which is kind of a scary thought. If this part of the brain is damaged, it erases of us being the humans that we are today. Jean also brought up another important concept along with the use of the neocortex and that is evolution. It is imperative to understand that the neocortex has evolved over thousands of years to reach the point that it has in human’s today- if we didn’t have the function of the neocortex that we can safely assume that we just wouldn’t be as highly evolved.  Nana brought up the insects in her post and justifies that even though these organisms lack a highly developed brain they still retain certain instincts including survival, reproduction and social community. The neocortex is extremely important to us as human beings but could we survive without it, yea, we could.  This thought involves the thoughts of the philosopher that Anna brought up that summarized the brain as a product of evolution that in fact has limitations. We all possess limitations in higher thinking- it could be that we lack stellar mathematics skills or problem solving techniques…all of these things could be rectified if we were to concentrate on these certain things and improve upon them thus making our intelligence increase and hopefully, these skills would be passed on to the next generation. The brain which includes the neocortex is clearly a product of evolution in my opinion.  Also changing the subject to the “I-Function”, this concept absolutely fascinates me. When we were discussing Christopher Reeve, the power of the brain and the nervous system and all that came with it was simply mind boggling to say the least.  I am not exactly sure how to formulate my opinion of the “I-Function” into words so I will not attempt to confuse myself and others but I will say that I look forward to hearing more about it and the importance and role that it plays in the conscious and unconscious.

Caitlin Jeschke's picture

Sensory neurons- 1, "I-function"-0

            In response to Lyndsey’s last few lines, I think that the issue of whether or not other animals/organisms have consciousness, and, if so, to what degree they are aware of themselves and other individuals, is an intriguing one.  However, I don’t think that we will ever be able to find answers to this question, just as we will never be able to know what another human is thinking.             

           That said, I really enjoyed class on Thursday.  The “I-function” discussion gave me so many new things to think about, and I was surprised by the results of our finger-waving experiment.  Based on my experience, many people (outside of our class at least) seem to think that the “I”, or whatever it is we have inside of us that makes us aware of ourselves, and makes us identify ourselves as individuals…is sort of like the control center of behavior.  To put it in terms of our class model, the “I-function” is seen as the “all-mighty” box, capable of integrating the patterns of signals that we receive from all of our sensory neurons, and sending out signals to our motor neurons to generate behavior.  Some people in the forum have suggested that the “I-function” could be “the mind”.  However, I think that such descriptions tend to overstate the importance of the “I” box in relation to the other parts of the nervous system.  During our Christopher Reeve discussion, we decided that he was not able to move his foot because “He” was no longer connected to that foot.  To me, this seems to emphasize the fact that the foot’s function has been compromised by the severing of the spinal chord.  In reality, though, the “I-function” has more of a handicap than the limbs—while the limbs still retain their ability to react to many kinds of input, the “I” box can no longer send signals to the majority of the body.             

            The experiment that we performed in class (trying to create smooth eye movements without the aid of a visual stimulus) is another example of how the “I-function” needs input from other sources in order to take full advantage of the actions that the body is capable of performing.  When I tried to rotate my eyes smoothly simply by visualizing a smooth movement, it didn’t work.  However, when I started waving my finger back and forth in front of my face, my eyes moved smoothly.  The visual input was needed to make up for the shortcomings of the “I-function.” It may be true that 99% of the neurons in the body are interneurons.  However, sensory neurons are clearly still crucial, because “We” are evidently not very powerful without them.

Angel Desai's picture

Self-reflection, manichaeism, and more

So many things to address! I really liked Lyndsey's queries concerning animals as related to the I-function. The philsopher A. MacIntyre wrote that while animals can feel pain and joy and intelligence in the same way that humans can, the key difference between the two lies in the human ability to self-reflect, or, the more or less physical manifestation of the I-function. We constantly ponder the human condition, the connection between morality and virtue, and even the relationship between the conscious and the unconscious mind. During class on Thursday, I had the suspiscion that perhaps the neo-cortex was strongly linked to the I-function, but after reading Lyndsey's comments and recalling MacIntyre's argument, I'm not so sure anymore. While, for example, my dog knows when he has committed a crime in our household, I am fairly sure he does not spend his days wondering why certain rules have been set in place or even the legitimacy of the institution which has created those rules. I am now beginning to believe that it is this mode of self-reflection that somehow links the mind and the brain.

 Another interesting point of contention was the discussion we had at the end of class on Thursday which mentioned the I function model as an illustration of distinct dualism between the conscious and the unconscious mind. Although this next thought may be painfully irrelevant, the point of dualism reminded me of the Manichaen belief in dualism as inherent in all aspects of life-the same type of distinction which can be made between the mind and the brain. I've forgotten what my original point was with this, but I'll think on it...

Lyndsey C's picture

a lot of questions!

I really enjoyed our discussion on Thursday because it cleared up a discrepancy I was struggling with earlier in the semester. so if the I-funtion is the conscious part of the mind, what is the unconscious? Are we categorizing actions into the processes carried out by the I-function? I am trying to piece together the puzzle in such a way that I can further support my earlier notion that the mind is a separate entity which works together with the body. Maybe I missed the boat, but did we assign a location of the I-function within the brain? Maybe it can't be located, since the brain isnt exactly specialized in such a way, but I guess what I'm trying to figure out is what happens to people who are in a coma. what happens to the I-function? can we ever really know? how much of the I-function is compromised during a coma? many people have described that loved ones who are in a coma still seem to be aware of certain things that are going on in the room or that they are "listening" to people who visit them in the hopsital. what about people who's prognosis is improved when they have people read to them when they are in a coma? does this have something to do with the I-function (the self) and motivation? animals lack an i-function, right? but what makes them aware of their separateness from others if they don't even cognize that they possess a self? and what about domesticated animals who's sensitivity to others seems to be heightened? how can they do this without an i-function?
Caroline Feldman's picture

Class was very interesting

Class was very interesting this past week. I searched the web and found that researchers are starting to apply technology to find the “self” ("I" function) in the brain. Certainly the most crucial aspect of the self is self-awareness—the capacity the self possesses to reflect upon itself. This is important. If the self was unable to think about itself, it would not know that it exists. Without self-awareness there still would be a self but we would not know about it. We could not contemplate our existence and unpreventable death, describe who we are and develop an identity, have a sense of ownership (“I did this; this is part of who I am”), or recollect past personal experiences that at least partially explain why we are who we are. In light of this paramount significance of self-awareness, a more contemporary question is: What precise brain areas exhibit increased activity when people engage in self-reflection?
Emily Alspector's picture


sorry, also, can someone help me differentiate between I-function and metacognition?
Emily Alspector's picture

more on sleep

Like Jackie, the first thing I thought of when Reeves' name was mentioned was our capacity to dream. How does I-function come into play when we are running in our sleep, yet laying still in bed. Also, there are individual differences (some people twitch in their sleep, some people sleep walk, some experience sleep paralysis as noted above) so how can any of this be accounted for? Dreaming states have always particularly interested me, so while I don't really have answers, I have many questions. I am tempted to say that perhaps the neocortex has something to do with dreaming or perhaps I-function awareness, since REM activity (I don't think) has not been studied much in animals other than humans.

I also liked Jean's (jchung01) mention of evolution. We haven't had a similar ancestor with reptiles or amphibians for millions of generations, so I'm not sure this is a question that can be answered with "Well, we have this ability and they don't so that's must be attributed to the neocortex". Although the warm-blooded argument intrigued me, I don't think the function of the neocortex can be so easily surmised.

Jackie Marano's picture

Toned-down Reeve's phenomenon

I was thinking a bit more about what we discussed in Thursday's class about the "I-function" and the way that the brain is related to the rest of the nervous system. I was really amazed by the small activity that we did in pairs; the nervous system helps us make smooth eye movements when we focus on a moving finger, but when the finger disappears, we, as the "I-function," cannot mimic this smooth movement without the matter how hard we try. I think this example tied in perfectly with our discussion about Christopher Reeve as someone who had an "I-function" and function in the rest of his body...but the two could not work together, they just coexisted.

On this line of thinking I tried to find evidence of other ways in which we can see how the "I-function" is, in fact, just a piece of the nervous system that can function by itself. While researching I stumbled on a rather interesting topic that is less severe and more temporary than Reeve's case, something called OBE (out-of-body experience) that is associated with lucid dreams and sleep paralysis: One site ( said "During REM sleep, the muscles of the body, excluding the eye muscles and those responsible for circulation and respiration, are immobilized by orders from a nerve center in the lower brain. This fact prevents us from acting out our dreams. Occasionally, this paralysis turns on or remains active while the person's mind is fully awake and aware of the world..." and this would be termed sleep paralysis.

And for a little more on sleep paralysis I checked Wikipedia, which said: "OBEs are often initiated through lucid dreaming, though other types of initiation also used. In many cases, people claim to have had an OBE, reported being asleep, on the verge of sleep, or having been asleep shortly before the experience. A large percentage of these cases referred to situations where the sleep was not particularly deep (due to illness, noises in other rooms, emotional stress, exhaustion from overworking, frequent re-awakening, etc.). In most of these cases, the subjects then felt themselves awake; about half them noted a feeling of sleep paralysis. "

With all of the above stated, I think my main observation is that the sort of coexistance between the brain and the remainder of the nervous system exists even when the "cables" connecting them are NOT cut!!!

Rica Dela Cruz's picture

I find Jackie's comment

I find Jackie's comment about coexistence between the brain and NS without cables being cut very interesting. I think another example of this is hypnosis. Unlike OBE, however, one is alert the whole time and aware of their surroundings. When someone is hypnotized, their conscious mind is lessened so that they are in a very relaxed state and their subconscious mind opens up so they are thinking with only their subconscious mind. Therefore, they do things without consciously know they are doing it. When a person is hypnotized and someone else tells them their tongue has swollen up, the hypnotized person will feel a sensation in their mouth and begin to talk in a funny manner because they actually think their tongue has swelled up. What amazes me is that the hypnotized person does not remember their actions after they "wake up". Hypnosis is another example of how there can be inputs in the brain that produces outputs, but the "I-function" of the brain is not aware of these outputs. 

I have also learned from this website,, that people experience forms of hypnosis everyday. These include reading, watching television or a movie, driving, and daydreaming. It is amazing to me that actions can still exist even when our "I-function" is shut off. 

Paul Grobstein's picture

sleep paralysis and cables

Nice connection. Quadriplegia can be understood in terms of trauma that cuts "cables", but its very much worth beginning to catalogue phenomena that might sense in term of cables tht are either normally missing or are reversibly inactivatable.

For more on sleep paralysis itself (which we'll return to later in the course), see Sleep Paralysis: Awake but Still Asleep, Mismatch Between Brain's Expectation and Sensory Input, and REM and the I-Function, and readers' comments following those student papers.

mkhilji's picture

Motion Sickness

Over the weekend a couple of friends and I made a trip to KOP, in a rush and too lazy to put all the seats up in the back of the van we all decided we would sit in the back on the ground. After about 5 minutes one of my friends began to feel nauseous and informed us that she experiences motion sickness. This is something that I am used to from my sister whom regardless of how smooth or straight forward a drive may be she would some point in the trip have to vomit. This became something that was expected from her always and became a fighting point amongst the rest of the family—as none of us wanted to sit next to her in the car or in the plane. It was interesting because I remember that any time someone in my family became motion sick we would blame them for “eating too much” or for falling asleep and not keeping their eye on the road. Reading over Hiro Takahashi’s webpaper Another Explanation for Hallucination during Sleep Paralysis: Mismatch between Brain’s Expectation and Sensory Input, it was proposed how motion sickness results from the mistracking of the sensory information in the brain. This brain confusion requires a high level of serotonin. Nausea and vomiting in a moving vehicle result from the mismatch in the brain. I guess this may also explain why some individuals complain of headaches or nausea when reading a book in a moving vehicle too. Now I realized that the symptoms of a headache, nausea and vomiting that take place in a moving vehicle is because the set of different sensory inputs do not match with any of the previously stored neural patters and the brain automatically interprets this mistracking as the effects of neurotoxins. Would these neurotoxins be defined as aliens to the several small boxes that make up our nervous system? If this is the case then why is it that motion sickness is not a symptom that everyone suffers from?

As a response to these supposedly neurotoxins the brain triggers vomiting as a defense mechanism to expel the “poisons from the stomach” in which the toxins have possibly entered with food”—this is the common system of vomiting that may result from food poisoning or some sort of flu. However when the mismatch happens in the brain, the alarmed brain misunderstands that some poisonous agents have entered the stomach, and it probably signals to release more serotonin to induce vomiting so that the toxin will exit the body.

This is thus a result of mismatching between the brain's expectations and sensory input--and can be related to the motion sickness people may experience from roller coaster rides or virtual dimension games.
Anna G.'s picture

I liked the idea of the

I liked the idea of the I-function being incorporated into the box we said was the nervous system. I was reading an article online by Steven Pinker that related well to this dilemma that we seem to be facing by trying define where this "I" sits in the brain.

 In the article, he says, "Another startling conclusion from the science of consciousness is that the intuitive feeling we have that there's an executive "I" that sits in a control room of our brain, scanning the screens of the senses and pushing the buttons of the muscles, is an illusion." 

He goes on to explore the different reasons why we might be sealed off from what goes on in our mind; our unconscious and conscious minds separate.

 "Evolutionary biologist Robert Trivers has noted that people have a motive to sell themselves as beneficent, rational, competent agents. The best propagandist is the one who believes his own lies."  

This is an interesting point to think about; that perhaps we are really just removing ourselves from reality to increase our own biological fitness and assure our survival.


 I especially like the idea of the philosopher Colin McGinn, whose ideas Pinker summarizes as, "The brain is a product of evolution, and just as animal brains have their limitations, we have ours. Our brains can't hold a hundred numbers in memory, can't visualize seven-dimensional space and perhaps can't intuitively grasp why neural information processing observed from the outside should give rise to subjective experience on the inside."  

I feel like this hits the nail on the head in terms of defining the problem we have been struggling with in class. We cannot comprehend how sensory input + a hunk of meat = emotions, consciousness, us. This has good evolution reason behind it, there is no need for us to understand; it wouldn't do anything to increase our biological fitness. In fact, subjunctive experience, our personality, everything we hold sacred, might just be side effects of cerebral cortex expansion due to its ability to increase group survival due to language skills for communication and reasoning for reciprocation.'s picture

the answer might be a lot more obvious than we think...

I see above that Nana and Molly have a heated debate on what the neocortex actually does. And I must admit, I seriously have no clue.

But I remember in class when Dr. Grobstein asked the question of what is the difference between mammals and all other organisms, we had a lot of things to list. There are simply so many evolutionary traits that provided the mammals with the ability to survive into the status that they have reached now (or we...haha.oopz.).

Anyways, i see that some suspect that the neocortex provides the ability of mammals to communicate or learn, and then there are questions applying to other organisms that have a way of communicating. Then comes in the aspect of learning and instinct vs. non-instinctual (is that even a word?) behavior.

I think that we need to stop setting this boundary. Yes, some can argue that the sophistication of mammals' behavior vs. non-mammalian behavior is much higher, but if you think about the traits that evolved in mammals, the abilities required to pursue those evolutionary traits are not all instinct or not our instincts. It is all a mixture of consciously thinking and performing certain behaviors as well as also having the instinct to notice the fact that one is given these traits. Thus, the neocortex is probably a supplementary add-on along with the rest of the evolutionary traits of mammals in order to completely know how to take care of themselves. It's probably, really not that complicated.

For example, mammals have mammary glands.  The fact that we put the baby against our breasts to feed them is a conscious thing.  The whole  maternal usage of mammary glands is instinct.  Thus, this action and knowledge of its purpose and usage is a mixture of voluntary movement as well as animal instinct.  However, the knowledge of mammary glands is knowledge that only mammals will know and no matter how hard we try to educate an ant, lizard or eagle about mammary glands, they will never know, especially since they have none.  

Thus, the neocortex is simply a supplementary part of pursueing the evolutionary traits that have come along when becoming a mammal.  

I hope this made sense.... 


Jessica Krueger's picture

For example, mammals have

For example, mammals have mammary glands. The fact that we put the baby against our breasts to feed them is a conscious thing. The whole maternal usage of mammary glands is instinct.

I'm not sure what your argument is overall, but I think I agree to a certain degree. While breastfeeding is inherently mammalian (baring platypuses), it often requires overt, verbal instruction to get a human female to breast feed her infant properly. However, I would argue that "knowledge" is a pretty exclusively human concept and that there are plenty of mammal-females who are very adept at nursing without any instruction. The argument that lizards or birds will never have "knowledge" of mammary glands could also be said of a cat who will never know the joy of grasping with an opposable thumb.


Simone Shane's picture

ok, not really related to

ok, not really related to this topic, but this was one of the headlines on the BBC this afternoon:

It discusses a new way to potentially fix spinal cord injuries

Anna G.'s picture

Also on this...a different

Also on this...a different approach...


nasabere's picture

And what about bees and ants?

"Although it is difficult to separate humans from other mammals, the idea that all mammals do a certain amount of teaching and babysitting, even though some mammals end up as solitary creatures, does seem to suggest that the neocortex causes some sort of instinct to form a community, to ensure the success of procreation, to pass on behaviors not just through genes but also through parenting."

What could be more sophisticated than the multiple communication systems of bees? And ants for that matter. They have very highly-developed social organizations. In addition, it is commonly thought that "behaviors and actions for the survival of the individual and preservation of species" are part of the more "primitive brain," which is not exclusive to mammals. I don't know how I feel about that, but at any rate, "survival" and the "perpetuation of the species" seems to be an innate characteristic of all living organisms. I believe that the neo-cortex transcends such fundamentally basic functions.

Molly Pieri's picture


Perhaps what is 'unique' to animals with neocorteces (neocortexes? sp?) is not that they have the ability to understand complex communication systems, but that they actively must learn these communication systems... Similarly with the idea of parenting I was tossing around earlier- maybe what is significant about the time during which mammals and birds are cared for by parents is that during this infancy period they learn from their parents. (I don't think that this necessarily must include a parental figure actively teaching, chimps certainly have learned, shared behavior with very little active teaching by older members of a community, but a lot of active learning by young...) I'm not certain how bees understand their crazy scent-dance system of communication, but I don't think that it is something they go about learning, rather, I was under the impression that it was something instinctual... Just a thought.


Simone Shane's picture

I mentioned metacognition

I mentioned metacognition before, and I think it really gets to a lot of what eambash is talking about in terms of studying ones own inner states and reflecting on self-identity. I would like to guess that all of that is found in the neocortex, but from everything I've ever learned, only humans have metacognition. Thus, if other mamals also have a neocortex but no metacognition, metacognition could indeed be located anywhere. However, eambash also talks about how much white matter there is and I think the size of the neo cortext. Maybe humans have crossed the threshold size and have thus acquired metacognition. Since metacognition is the awareness of oneself, could the "lower" version found in non-human mamals be just general consciousness? That is, the ability to consciously think?

mcrepeau's picture

Ask the Chinese Philosopher


But as much as we are seemingly liberated, or "enhanced" by metacognition we are also limited by it:

One of my favorite stories as a child came out of a short story anthology called "Anima", it's called "Happy Goldfish" and it goes like this:

One day a wise Chinese sage and his disciple were walking by a pond in a garden when the wise sage sat down to rest beside the pond. There were goldfish that lived in this pond and when the Chinese sage saw them swimming in the jade colored waters at his feet he smiled and said "They are happy." His disciple turned to his master and said "You are not a goldfish, so how do you know that they are happy?" To which the wise Chinese sage replied, "You are not I. So how do you know that I do not know that they are happy?"

Also, out of the same anthology, although in no way exclusive to it, came the story of the Chinese Philosopher who dreamed he was butterfly only to wake up and then ponder whether or not he was actually a philosopher who had dreamed that he was a butterfly or a butterfly that was now dreaming it was a philosopher.

Basically, what I'm trying to say is that our sense of metacognition, the range of our I-Box, is inherently constrained to the extent of itself, and, although we can extrapolate, and infer the experiences, realities, and perceptions of other people, other organisms really, we can never fully comprehend their experience of life, their sense of awareness, we can only superimposed our own perceptions and experiences over them (thus we anthropomorphize, personify, etc.), and either subtract or add on to that state of perceptions, etc. based on our sense of how “qualified” a particular organism is in a particular scenario. However, although we can observe that there are physiological and biological differences in the nervous systems of different organisms and infer that that must mean something, exactly what that meaning is, or the extent to which that meaning carries, is something that can never by concretely proven by the very fact that an individual can never truly understand the awareness, or perception of another, maybe even themselves. For, as was mentioned elsewhere in the forum as the "theory of mind", there is a you that exists in your own "mind", your own sense of "I-function", and there is also a "you" that exists in the minds, perceptions, the part of the brain that builds a representation of you, etc. of others, and each one is a little different, a little unique unto itself, and it is a you that, ironically, you may never know or understand or even be aware of.

Jen Benson's picture

good point

I definitely agree that we should not dismiss the possibility that other species (especially other primates or mammals, and dolphins) have the capacity to have an I-function in their nervous systems, since we can never know their subjective experiences.
nasabere's picture

How does one

How does one measure metagcognition?
eambash's picture

Forging pathways backwards

Perhaps by behavior (to invoke a familiar argument)!
Molly Pieri's picture

Theory of mind measurments...

One fun little test they do to determine metacognition and the like in humans is this:

Children will watch a puppet show or play in which the puppet/actor has a cake. The puppet/actor will tell the children that he is going to hide his cake underneath the Green Couch (for example). The puppet/actor will ask the children not to touch his cake while he leaves the room. After the puppet/actor leaves the room, another adult enters (possibly the puppeteer), and moves the cake from underneath the Green Couch into the Red Cabinet (both set pieces in the puppet show/play). She then asks the children where the puppet/actor will look for the cake when he gets back.

Children under the age of three will answer "in the Red Cabinet" without hesitation- after all, they know that the cake is in the Red Cabinet, why shouldn't the puppet/actor?

Children around 4 or 5 will hesitate, and not really know where the puppet/actor will look for the cake.

Children over the age of 5 will answer "He'll look under the Green Couch, but he'll be wrong, because I know it's in the Red Cabinet"

This establishes that it isn't until about the age of 5 or 6 that humans develop a theory of mind. In other words, it isn't until 5 or 6 that we are not only self aware, but we are also aware of others, and that these other's awareness of the world is different from our own. (That is, not only can we posit a self and an other, but we posit a self and an other who can also posit his/her own self, which is a self conceivably different from the self we posit for them as an other...Okay, enough of my philosophy class....)

I'm not sure how this ties in with our discussion of the neocortex, but I thought it was an interesting experiment none the less. I've also read that some studies have shown some great apes (probably either chimps or bonobos, I can't remember...) to have theory of mind capabilities, but I've never actually read the study, and I've read many other articles that say this claim is a load of garbage.... Any way, I'll see if I can find any links for people to read more about this some time, but right now I have to go to class.




Jen Benson's picture

Yes, some researchers have

Yes, some researchers have argued that orangutans and chimpanzees (and humans from a certain age) have self-awareness. Such statements are based on the fact that they pass tests of mirror recognition in which they see in a mirror that their face has been smeared with red paint or chalk through recognizing the reflection as their own.
If you would like to read more about it, here is an article
If that doesn't work, and you want to read up on it more, this Anthro journal can be accessed through Tripod from either HC or BMC. I'm sure a PsychInfo search would also yield some interesting results about some kinds of monkeys having self-awareness.
Monkeys, apes, mirrors and minds: The evolution of self-awareness in primates
Journal Human Evolution
Publisher Springer Netherlands
ISSN 0393-9375 (Print) 1824-310X (Online)
Issue Volume 2, Number 6 / December, 1987
Simone Shane's picture

What you're describing is

What you're describing is Theory of Mind or the ability to represent others' representations. I took a class all about it with Kim Cassidy who did a lot of research in that subject. There are many different types of theory of mind and what you're describing is first order theory of mind. There is also second order theory of mind which is the ability to represent others' representations of someone elses' mental states. The ability to successfuly pass second order false belief tests comes around age 8 or so. Also, autistic children have a lot of difficulty with theory of mind tasks. Do they have compromised neocorteces?

Theory of mind is only one type of metacognition as it requires one to represent someone else's cognition. What about the ability to represent one's own cognition? I know that metacognitive skills are taught in some schools to help children realize what they understand and what they need to study more, etc... Are there any studies looking at these children's brains before and after these metacognitive lessons?