neurones and depression

[nari]

From the September issue of Scientific American ( a great issue, this one, even though I do not understand the enormity of the post - Einstein work done in physics!) comes a little snippet:

"People with major depressive disorder have about one third more neurones than average in a region of the thalamus that regulates emotion, suggesting that anatomical abnormalities underlie the condition".

From the American Journal of Psychiatry, July 2004.

I don't have any access to this journal, but this deduction of extra neurones causing depression is interesting. Why not the other way around, that the chemical inbalance causes extra sprouting?

What do people think?

Nari

[bernard]

Hi Nari,

Here is the American Scientist
http://www.sciam.com/issue.cfm?issueDate=Sep-04

the issue of November shows music in brain article
http://www.sciam.com/issue.cfm?issuedate=Nov-04

Here American Journal of Psychiatry
http://ajp.psychiatryonline.org/content/vol161/issue7/

the abstract you cited
http://ajp.psychiatryonline.org/cgi/content/abstract/161/7/1270

[bernard]

I put Music and the brain in the general section. :wink:

[Diane]

this deduction of extra neurones causing depression is interesting. Why not the other way around, that the chemical inbalance causes extra sprouting?

Interesting question, and I for one, don't have a clue. Perhaps all neurones need to feel connected, and if they don't (if there are too many of them without "homes" (i.e. synapses) for them all, they get "depressed" (leak out more neurochemical substances. (Diane's conjecture only.)

On another topic, a young friend of mine is a scholteacher, and she plays heavy stimulating music in her classrooms, which keeps the ADD children hugely on track, they bop along and get all their work done. They need all this brain multitasking in order to get anything done. Sounds like they have way too many synapses for the number of neurones. By the way Bernard, love that big music article, thanks.

Diane

[rolf]

Hi Nari!'

"People with major depressive disorder have about one third more neurones than average in a region of the thalamus that regulates emotion, suggesting that anatomical abnormalities underlie the condition".

Isent it quite normal for people who uses their brain in one way or another increases the area of the brain which which is dominantly used.
Women have a greater limbic area than men.Why,they are more in contact with their emotions.(Daniel G Amen,-"Change your brain ,change your life")Read espesially chapter tree,Looking into love and Depression.
I think this book will give you some answear Nari.
RIN

[nari]

Bernard, thank you for your copious response! You never cease to amaze me - do you ever sleep?? Or eat?

The music and the brain article is good - I will probably buy the magazine, but it takes months to filter through to Oz.

Rolf, thanks for the book reference. On an entirely different topic (or is it?) are you familiar with the movie "101 Reykjavik"? Amazing atmospheric music that really compounds the bizarre nature of the film.


Nari

[nari]

Hi again Rolf

Isn't it rather peculiar that the areas identified in the above article (mediodorsal, anteroventral/anteromedial thalamus) are linked through other bits and pieces around the brain that also perform multiple and complex functions?
So the 37% extra neurones are specific only to depression?

or not?

If the depressive state results in extra neurones because of higher 'use' - what causes the depressive state?
If the depression is the result of extra neurones, what causes that?

...chicken and egg stuff, to my entangled brain.


Nari

[ian s]

complex....however look at the studies on the interesting article on musicians .....the left hands fingers neurons were increased due to the repetitive practice, the right bowing hands were not .
Rama's work on mirror neurons may be useful ie learning via mimmicary ....maybe as all things its a combination of genetic predisposition , exposure to repeated negative stimulation and a predisposition to ANT's......If the violinist did not practice millions of finger patterns the left hand representation would not enlarge and perhaps if the pattern of behaviour leading to millions of negative thoughts changed the neuronal pattern would change too?
Back to trying to make some more neurons -- difficulty with the D to C sharp change over at the moment !
ian

[rolf]

Hi Nari"

You wrote ,"what causes the depressive state?"

Lack of energy,due to decreased sleep,nutrition deficit,to little exercise ,to little love,etc etc and a mind which is disposed to se more limits than possibilities!

RIN

[nari]

Thanks Rolf, but I was thinking (but didn't write it) more of endogenous depression states rather than reactive depression.

I don't think there was a distinction made in the studies.


Nari

[bernard]

Nari,

I eat, of course, and sleep too!

Rolf,
I need to read the book for sure!

About neurons =>

A task involves these steps;
1/ put together all the possible areas which are tought as usable.
2/ try!
3/ select the fastest and more synchonous neurons for the goal
4/ change some synaptics connections to enhance the functioning
5/ enhance the neural network with a discard of all the unecessary things


The maturation goes thru a phase of draft then of reducing, to finish with a phase of acceleration!

Depression seems to be stuck in the early phase?

[bernard]

So, my actual opinion is (as many thinkers of the last century);

The previous conclusions come from a book by Jean-Pierre CHANGEUX, but I think that the Synaptic Self by LEDOUX is quite similar.

Performing a task (moving, thinking, playing music...) needs first associations, and then elimination of useless neurons, and then corrections of synapes positions to augment the necessary synchrony between the neurons.

The more the task is well done the less neurons it uses!

[bernard]

http://jn.physiology.org/cgi/content/abstract/92/4/2405

J Neurophysiol 92: 2405-2412, 2004; doi:10.1152/jn.01092.2003
0022-3077/04 $5.00

Changing Brain Networks for Visuomotor Control With Increased Movement Automaticity

A. Floyer-Lea and P. M. Matthews
Centre for Functional Magnetic Resonance Imaging of the Brain, University of Oxford, John Radcliffe Hospital, Headington, Oxford OX3 9DU, United Kingdom

Submitted 11 November 2003; accepted in final form 10 February 2004

Learning a motor skill is associated with changes in patterns of brain activation with movement. Here we have further characterized these dynamics during fast (short-term) learning of a visuomotor skill using functional magnetic resonance imaging. Subjects (n = 15) were studied as they learned to visually track a moving target by varying the isometric force applied to a pressure plate held in the right hand. Learning was confirmed by demonstration of improved performance and automaticity (the relative lack of need for conscious attention during task execution). We identified two distinct, time-dependent patterns of functional changes in the brain associated with these behavioral changes. An initial, more attentionally demanding stage of learning was associated with the greatest relative activity in widely distributed, predominantly cortical regions including prefrontal, bilateral sensorimotor, and parietal cortices. The caudate nucleus and ipsilateral cerebellar hemisphere also showed significant activity. Over time, as performance improved, activity in these regions progressively decreased. There was an increase in activity in subcortical motor regions including that of the cerebellar dentate and the thalamus and putamen. Short-term motor-skill learning thus is associated with a progressive reduction of widely distributed activations in cortical regions responsible for executive functions, processing somatosensory feedback and motor planning. The results suggest that early performance gains rely strongly on prefrontal-caudate interactions with later increased activity in a subcortical circuit involving the cerebellum and basal ganglia as the task becomes more automatic. Characterization of these changes provides a potential tool for functional "dissection" of pathologies of movement and motor learning.

--------------------------------------------------------------------------------
Address for reprint requests and other correspondence: P. M. Matthews, Centre for Functional Magnetic Resonance Imaging of the Brain, University of Oxford, John Radcliffe Hospital, Headley Way, Headington, Oxford OX3 9DU, UK (E-mail: paul@fmrib.ox.ac.uk).

Here is a reference about this behavior.
Thus depression is a state of going nowhere. The reduction process is unable to take place because there is a lack of synchrony?