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Do Piaget's developmental phases correspond with physiological phases?

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rousseau

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I assume no, but now that I'm surrounded by a bunch of babies I'm curious if there are any major neurophysiological phases of development, or instead the brain simply grows and becomes more neurally interconnected with time.
 
Both Piaget and Vigotskiy understood that the social-learning environment had a lot to do with the appearing of the different phenomena and phases (well, Vigotskiy from the start, Piaget was more of an innatist but he later came around).

It's hard to pinpoint these as physiological, when nature and nurture are both involved and each indispensable.
 
rousseau said:
I assume no, but now that I'm surrounded by a bunch of babies I'm curious if there are any major neurophysiological phases of development, or instead the brain simply grows and becomes more neurally interconnected with time.
Click to expand...

It is possible and very likely. The problem is that these changes would be in brain structure, which is very difficult to observe. Beyond that, there are a lot of changes in brain structure simply because of normal growth. The brain is increasing in size, so the developmental phases could be correlated with brain mass, but there might be unseen structural change which account for the phase development. Up to this point in scientific advancement, knowledge about brain development is more likely to come from studying defective brains. This gives a structural skew to data and most researchers recognize this. There are many new research tools which now allow researchers to map and graph normally performing brains. This will certainly lead to many new discoveries.

I am sure, as I type, someone is strapping a toddler into an MRI, with the hope of answering your question.
 
I've actually done a little bit of research on quantitative neural anatomy, so I feel like I should be able to contribute more to this discussion than I think I will be able to. Unless you want to talk about developmental changes in the murine olfactory system. Then I might be able to contribute more.

But looking at humans, as far as I am aware, the brain does not simply "grow." Brain volume/mass peaks during adolescence and stays relatively stable during adulthood. There is minor shrinkage of brain volume as we age, although, I'm not sure how well studies have been able to separate "normal changes" from "pathalogical aging" (i.e. dementia). Obviously, someone who has advanced Alzheimer's will show dramatic reductions in brain size.

Neuron number and connectivity is either at its peak at birth or shortly after birth in humans. Actually, during gestation there are many more neurons at certain points, at least cortical neurons, and the number at birth is definitely smaller than in pre-natal development. Looking at a postnatal brain, we go through "synaptic pruning" whereby total neuron number and total synapse number declines significantly by the time you are an adult.

http://en.wikipedia.org/wiki/Synaptic_pruning#Variations_of_Synaptic_Pruning

If you want to look for physiological correlates to Piaget's developmental phases, I would start by looking at the phenomenon of synaptic pruning in more detail.

Also, there is the phenomenon of myelination , whereby long-range axons get "insulated" by a myelin sheath, generally resulting in a faster signal with less signal loss. I believe the last parts of cortex to be myelinated are frontal lobe areas, and that happens around the early 20s.
 
Bronzeage said:
rousseau said:
I assume no, but now that I'm surrounded by a bunch of babies I'm curious if there are any major neurophysiological phases of development, or instead the brain simply grows and becomes more neurally interconnected with time.
Click to expand...

It is possible and very likely. The problem is that these changes would be in brain structure, which is very difficult to observe. Beyond that, there are a lot of changes in brain structure simply because of normal growth. The brain is increasing in size, so the developmental phases could be correlated with brain mass, but there might be unseen structural change which account for the phase development. Up to this point in scientific advancement, knowledge about brain development is more likely to come from studying defective brains. This gives a structural skew to data and most researchers recognize this. There are many new research tools which now allow researchers to map and graph normally performing brains. This will certainly lead to many new discoveries.

I am sure, as I type, someone is strapping a toddler into an MRI, with the hope of answering your question.
Click to expand...

They better damn well be! This is information I need to know!
 
rousseau said:
Bronzeage said:
It is possible and very likely. The problem is that these changes would be in brain structure, which is very difficult to observe. Beyond that, there are a lot of changes in brain structure simply because of normal growth. The brain is increasing in size, so the developmental phases could be correlated with brain mass, but there might be unseen structural change which account for the phase development. Up to this point in scientific advancement, knowledge about brain development is more likely to come from studying defective brains. This gives a structural skew to data and most researchers recognize this. There are many new research tools which now allow researchers to map and graph normally performing brains. This will certainly lead to many new discoveries.

I am sure, as I type, someone is strapping a toddler into an MRI, with the hope of answering your question.
Click to expand...

They better damn well be! This is information I need to know!
Click to expand...

Here a couple of starting points

Dynamic mapping of human cortical development during childhood through early adulthood:
http://www.pnas.org/content/101/21/8174.full

Human Life Span Development chapter 1: http://www.cengagebrain.com/content/sigelman53409_0495553409_02.01_chapter01.pdf

I suggest you use scholar
 
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