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The Developing Mind: How Relationships and the Brain Interact to Shape Who We Are

maggie_simon's picture

While there are many surprising insights in Daniel J. Siegel’s The Developing Mind, I was most intrigued by how information from the brain and body combine as output to the mind. Merging class discussion with the material in this book offers two ways in which the internal processes of the brain combine with stimulus input from the body to give rise to a picture in the mind. The way discussed in class is that input from the body is supplemented by the brain before it reaches the mind, such as the filling in of the blind spots in the eye. A different way that was touched on in the book is the idea that the brain generates output to the mind that is supplemented by input from the body, such as when it looks to facial expressions to determine what kind of emotions the mind should be experiencing. Although only briefly mentioned in the book, this interaction between body and brain is so subtle that I would like to expand on it before returning to how input from the body is manipulated by the brain before reaching the mind. I will flush out this second idea by talking about the influence that a brain’s state of mind can have on how incoming information is received by the brain and passed onto the mind, using the specific example of memory.

I learned from Siegel’s book that primates are the only animals that have motor neurons in the skin of the face, and that facial muscles play a large role in the expression as well as perception of emotion. Siegel writes of an experiment in which subjects are asked to hold their faces in a certain way and are then told a story. The subject’s experience of the story directly relates to the way in which their facial muscles are held. When their faces are fixed so that they express sadness (unbeknownst to the subject who is simply asked to contort their muscles in certain ways), their interpretation of the story is sad, and likewise with other emotions. So, facial expressions play a significant role on how the brain experiences emotions. Recently someone asked in class whether it was true that forcing ourselves to smile can make us feel better. This finding suggests that the classmate’s question should be answered in the affirmative.

I find it intensely interesting that the way in which the muscles in our bodies (such as in our face) are held can influence the emotional state in which we find ourselves. Thus, the sensory input from our physical bodies can fill in the gaps in the brain’s attempt at feeling out its state of mind. In class we mostly talked about the opposite case, in which the brain fills in the gaps in sensory input. For example, we talked about the way in which the sensations that we experience are actually added to by the I-function so that there is more that reaches our mind than just the raw sensory input. Siegel shows that the way in which the brain fills in those holes can change according to such factors as the person’s state of mind.

Siegel defines a state of mind not as the emergent way that we feel or are thinking at a given time, but as the activity in the brain that is a result of the transfer of energy between neuronal circuits as webs of neurons receive, process, and output information. Certain systems of the brain are activated at the same time and can communicate with each other, affecting the processing of one another. These patterns of activity give rise to those emotions, thoughts or sensations that we can then consciously experience and share with others. Certain states of mind can become more common in a person because experiencing a certain state of mind makes it more likely to be experienced in the future.

This is due to Hebb’s axiom which suggests that neurons that have fired together in the past have a higher probability of firing together again in the future. Siegel writes that this ability arises from the modification of neurons themselves as well as the way in which they are wired and connected to other neurons. It is because of the phenomenon of Hebb’s axiom that experience can be saved as memory encoded in specific neuron firing patterns that are likely to activate again. These firing patterns translate into the memory of the experience. The capturing of experience in memory is an especially interesting example of the influence of a person’s brain and mind on their perception of their surroundings.

Memory is a subjective process because experience gives us things to remember, but how our brains remember those experiences plays a role in how we view ourselves in those memories. Furthermore, there are many layers to remembering an experience, not all of them accessible to the conscious mind, so how we remember an event can change overtime according to our new experiences or our state of mind at the time of recalling a memory. This fact seems to be a specific example of the idea discussed in class that our minds are constantly rechecking reality by comparing new input against past inputs. Memory, as a little piece of our reality, is also being reworked with the input of new experience. This constant reality check is one way in which the brain communicates with itself.

Siegel often repeats the idea that the brain communicates not just with itself but also with other brains. It does this by processes like those described above, such as through visual emotional cues, or the verbal sharing of memories, thoughts, sensations, and emotions. The exciting result of this idea is that we have the ability to change ourselves and others by sharing our brains with each other. By interacting with other people, we have the opportunity to change our own realities, as well as influence theirs. Not only are we changing our realities for the present and future, even the way that we interpret past experiences as memories can be modified. The overall message that I get from this book is that the brain is constantly changing and consequently a human’s state of mind, memory, and future experiences are not static. There is hope for those who are constantly dissatisfied with life. All they must do is change their habits, moods, and relationships so as to allow their brains and minds to grow in positive directions.


Siegel, Daniel J. The Developing Mind: How Relationships and the Brain Interact to Shape Who We Are. New York: The Guildford Press, 1999.


Paul Grobstein's picture

allowing brains/minds to grow

Sounds like a good idea indeed. And do think it is useful to recognize that "filling in" can be altered by "states of mind". Aren't those though just "states of brain"?