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Exploring Consciousness

natsu's picture

What is consciousness?

Consciousness is a topic that has intrigued and puzzled researchers for centuries.  However, even today there is no real set of criteria for consciousness that have been agreed upon, which creates a major difficulty for researchers who strive to scientifically examine this topic.  Of course, there have been some who have attempted to take on this challenge.  For instance, Seth, Baars, and Edelman (2005) proposed 17 criteria for consciousness including specific EEG signature, self attribution, conscious knowing and decision making.  Definitions of consciousness that have been offered so far tend to have a circular nature.  That is, consciousness is defined as “the subjective state of feeling or thinking about objects and events” (Griffin & Speck, 2003 p. 6).  At the same time, the word feeling is defined as “pleasurable or painful consciousness.”  In addition, various words such as awareness, reasoning and metacogntion are generally used as synonyms of consciousness for research in this field.  However, whether all or even some of these concepts are truly synonymous to consciousness is unclear, and the assumptions that we make perhaps impede progress in research on consciousness.  Not surprisingly, discussing consciousness in our seminar group also proved to be a challenging task, mainly due to our lack of solid definition for this multi-dimensional concept.  However, by wrestling with this challenge as a group, we managed to acknowledge our different ideas on consciousness.  Below, I will illustrate these diverse perspectives.              

One topic that was repeatedly raised in our discussion group was the relevance of our ability to recall events to the conscious mind state.  Are memory and consciousness intrinsically linked?  When we are asleep or when we “zone out”, we generally do not have any memory of what was happening during that time frame.  Yet, we are constantly losing our memories even when the memory formation happened at a time when we were fully conscious.  How long then must we be able to remember an event to be able to claim that we were conscious?  Furthermore, it is not at all difficult to come up with counterexamples to the memory-consciousness link.  For instance, HM, a patient who lives with severe anterograde amnesia from surgery induced brain injury, is incapable of sustaining information in his mind.  As a result, he cannot consciously remember information from one minute to the next.  Yet we do not hesitate to argue that he is fully conscious during that one minute.  Another example is trauma victims (Amelia, 2008).  It is well known that patients who suffer from intense traumatic events tend to completely erase the events from their minds.  However, it is hard to conceive that these patients were not fully conscious at the time of the event, as if they were unconscious, they would not choose to erase their memories.   

Another topic of interest concerns the relevance of passage of time to consciousness. When we wake up from sleep or anesthesia, we realize that time has relapsed without our awareness, which seems to agree with the idea that the unconscious mind state is not associated with an awareness of time.  However, does this imply that an awareness of the passing time is a criterion for consciousness?  We all have experienced the feeling of “time flying by” when we are enjoying ourselves even though we are fully aware of every moment of the enjoyable event and such meaningful experiences usually stay in our minds.  Due to our lack of clear criteria for consciousness, it is also difficult to determine whether certain mind states are conscious or not.  For instance, when we make decisions or take actions out of habit are we conscious or unconscious?  At first, learning how to drive or swim requires a high level of consciousness.  However, eventually even the most complex techniques associated with these skills become manageable without much thought.   In fact, a lot of the professional training that competitive athletes and artists go through seems to involve training the body to move in certain ways without the guidance of a conscious mind.  Consequently, the power of the unconscious mind state allows for some extraordinary complex skills.

Animal Consciousness

An issue that interests philosophers and scientist as well as the general public is whether consciousness is a uniquely human attribute.  How far down the animal kingdom does consciousness extend?  When Donald Griffin first expressed his argument on animal minds in his publication The Question of Animal Awareness (1976), the concept of animal consciousness was met with alarm and disbelief.  Griffin, who was a professor of zoology, noted that many animals are capable of adapting their behavior depending on the challenges they encounter, and argued that non-human animals must have consciousness, although they are probably not identical. The new discoveries concerning the surprisingly high cognitive capability of animals that have been made since then have moved the scientific community to gradually accept the notion that there may be a considerable amount of similarity between the cognition of animals and humans.  Today, the concept of animal consciousness has become a topic for scientific investigation that interests many.  Scientists argue that animal consciousness is important and relevant to research as it concerns whether or not it is meaningful to use animals as models for research concerning human beings.

The fact that there is no set of criteria or definition of consciousness creates difficulty in finding a way to accurately assess animal consciousness.  In humans, the standard, and perhaps the simplest, behavioral index of consciousness is accurate report.  Accurate report can be verbal self report of conscious perception but it can also include behaviors such as eye-blinking and lever-pressing.  Physicians routinely use accurate report to test patients for impaired consciousness.  In addition, thousands of human experiments use accurate report to study conscious perception.  However, people tend to be more skeptical of the usefulness of accurate report for examining consciousness in non-human species, especially as animals cannot verbally report whether they are consciously experiencing a specific event.

Hence, some researchers have turned to the brain to find evidence for consciousness in animals.  For instance, Baars (2004) points to the fact that both humans and non-human mammals show great difference in scalp EEG activity between waking consciousness and unconscious sleep.  During unconscious sleep, slow-wave global EEG appears to reflect highly regular and coordinated firing patterns. A great number of individual neurons in thalamus and cortex fire in a burst-pause pattern.  In contrast, waking EEG reflects irregular firing in the same neurons.  The similarities seen in the anatomy of the human and animal brains also suggest consciousness in some non-human mammals (Baars, 2004).  In humans, the thalamus and cortex are considered to be crucial for supporting the contents of consciousness.  It is known that consciousness is lost when sensory regions of the cortex and the intralaminar nuclei of the thalamus are damaged.  On the other hand, damage to other regions of the brain such as the cerebellum and the spinal cord does not lead to loss of consciousness.  When we look at animals, we find that all mammals posses well developed thalamus and cortex, suggesting consciousness in non-human mammals.

However, there are also species that have considerably different brain anatomy from mammals but still show behavioral signs of consciousness.  Accurate response is definitely observed in some birds.  For instance, ravens have the ability to follow gaze (i.e. gaze-following) and some birds that bury nuts before the start of the winter season have the ability to remember and retrieve their food once the surrounding scenery signals the end of the cold season.  Bees convey information about food sources by doing a ‘‘waggle dance”, meeting the ‘‘accurate report criterion”.  It has also been reported that bees have the ability to master complex navigational cues (Wertheim, 2003). 

Discoveries that non-human species are also capable of some surprisingly versatile behavior have led many researchers to argue that it is irrational to believe that animals do not think at all.  Today, scientists have shifted to adopt the idea that animals at least have some level of consciousness, though animal consciousness is most likely quite different from human consciousness.  To what extent are non-human species conscious?  Do animals experience sensations such as pain and desire (i.e. phenomenal consciousness)?  Can they perceive, introspect and retrieve stored memory (i.e. access consciousness)?  Do they have beliefs and self-awareness?

Temple Grandin is one scientist that has and continues to offer valuable insights on animal consciousness.  Grandin was diagnosed with Asperger’s Syndrome in adulthood and she believes that her professional training as an animal scientist and her high-functioning autism provides her with a unique perspective on animal minds.  Grandin relies largely on pictures for thought formation and decision making, unlike most typical individuals who think with words.  Her thoughts are always illustrated as pictures in her mind and language does not appear in these images.  She proposes that there exists multiple layers of consciousness and that “language is another layer of thinking which covers up the visual layers” (Grandin, 1998).  Her “autistic like consciousness” is quite different from typically developing people, but Grandin believes that it is likely to be more similar to consciousness in many animals.  She argues against researchers who believe that language plays a necessary role in consciousness and since animals are incapable of using language, consciousness does not exist in their minds (Terrace, as cited in Eakin, 2001). 

Grandin also believes that there are several other similarities between consciousness in people with autism and consciousness in animals.  She argues that both are much more focused and sensitive to specific detail that typical people tend to dismiss or are blind to.  In addition, typical people make quick interpretations of events based on what they already know and thus are often blinded by what they are actually seeing.  An experiment conducted by Simons and Chabris (1999) illustrates this tendency.  In their study, subjects viewed a video of two pairs of three basketball players passing a ball back-and-forth, and were asked to count the number of passes made between the players.  Midway into the clip, a person dressed in a gorilla suit appeared in the midst of the players, obviously an event that was quite unexpected.  Surprisingly, approximately half the subjects did not notice the appearance of the person in the gorilla suit.  This result was sufficiently replicated when the same experiment was performed in our group.  Grandin argues that this phenomenon in which typical people’s minds do not register unanticipated events (inattentional blindness) would most likely not occur for visual thinkers like animals and people with autism (Grandin, 2005).  Animals and people with autism are more conscious of the reality and not the interpretation. 

Not surprisingly, pet-owners in our group did not hesitate to state that their pets are conscious.  However, when questioned why, few could provide a clear answer.  Some talked about how they could observe various feelings in their pets such as fear, happiness, morality, empathy and social understanding.  It is interesting to note that we readily project our ideas of consciousness to others.  We all seem to have some gut instinct about consciousness that we cannot articulate and we use this instinct to judge whether another individual or animal is conscious, despite the fact that we have no way to confirm this.  One possible idea is that we use unpredictable behavior as a sign of consciousness in others (Grobstein, 2008).

Though Dennett remarked that theories on animal consciousness is a “mess” (as cited in Eakin, 2001), research in this area appears to have taken some interesting directions in the past few decades due to surprising discoveries and diverse insights.  Yet, Dennett raises an important question as we proceed in our exploration of consciousness: Do we really want to know all the answers to our questions on consciousness?  Throughout this semester, our group has explored several multi-faceted topics that have long been considered to be mysterious and difficult to define (e.g. love, pain, diversity and morality).  Researchers have studied these complex topics for various medical, commercial and ethical reasons, but knowing too much about some of these mysteries might reduce the pleasures of life (e.g. Rabinowitz, 2008).  While exploring consciousness without a solid, all-encompassing definition may be acceptable, perhaps it is necessary to take the time to define what we want to understand about consciousness and for what purpose.


Amelia. (2008, April 27). Memory not a part of consciousness. Message posted to /exchange/node/2388

Baars, B. J. (2004). Subjective experience is probably not limited to humans: The evidence from neurobiology and behavior. Consciousness and Cognition, 14(1), 7-21.

Grandin, T. (1998). Consciousness in animals and people with autism. Retrieved April 1, 2008, from

Grandin, T., & Johnson, C. (2005). Animals in translation: Using the mysteries of autism to decode animal behavior. New York: Scribner.

Griffin, D. R. (1976). The question of animal awareness: Evolutionary continuity of mental experience. New York: Rockefeller University Press.

Griffin, D. R., & Speck, G. B. (2004). New evidence of animal consciousness. Animal Cognition, 7(1), 5-18.

Grobstein, P. (2008. April 28). Issues re consciousness. Message posted to /exchange/node/2388

Rabinowitz, E. (2008, Feb. 24). Love: Do you really want to know? Message posted to /exchange/node/2075

Seth, A. K., Baars, B. J., & Edelman, D. B. (2005). Criteria for consciousness in humans and other mammals. Consciousness and Cognition, 14(1), 119-139.

Simons, D. J., & Chabris, C. F. (1999). Gorillas in our midst: Sustained inattentional blindness for dynamic events. Perception, 28(9), 1059-1074.

Wertheim, M. (2003). The zombie within: Christopher koch and the science of consciousness. LA Weekly, Retrieved, April 1, 2008 from


Paul Grobstein's picture

the relation between definition and research/inquiry

Maybe interesting research/inquiry creates/revises definitions rather than requiring clear definitions at the outset?