Science Daily - Dopamine - Food and Environmental Toxins Impair Cognition

[Guest guest]

Dear Arthur,

 

Thanks, I'll put it on the list. Yes, aspartame changes the dopamine

level of the brain and plays a big part in the addiction. And, of

course, aspartame reduces IQ and the Norway study shows aspartame

destroys the brain, especially in the area of learning.

All my best,

Betty

www.mpwhi.com, www.dorway.com and www.wnho.net

 

 

" DrE "

" Betty Martini " <bettym19

Food and environmental toxins impair cognition !!

Mon, 16 Mar 2009 15:33:35 -0700

 

 

 

Betty

 

This article seems to indicate that anything that reduces dopamine in

the brain,

has an adverse affect on learning !! Food and environmental toxins

impair cognition !!

 

'The Unexpected Outcome' Is A Key To Human Learning

<http://www.sciencedaily.com/releases/2009/03/090313145952.htm>http://www.scienc\

edaily.com/releases/2009/03/090313145952.htm

 

ScienceDaily (Mar. 15, 2009) - The human brains sensitivity to

unexpected outcomes plays a fundamental role in the ability to adapt

and learn new behaviors, according to a new study by a team of

psychologists and neuroscientists from the University of Pennsylvania.

 

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See also:

<http://www.sciencedaily.com/news/mind_brain/>Mind &

Brain<http://www.sciencedaily.com/articles/>Reference

<http://www.sciencedaily.com/news/mind_brain/intelligence/>Intelligence

 

<http://www.sciencedaily.com/news/mind_brain/child_development/>Child

Development

<http://www.sciencedaily.com/news/mind_brain/consumer_behavior/>Consumer

Behavior

<http://www.sciencedaily.com/news/mind_brain/neuroscience/>Neuroscience

 

Using a computer-based card game and microelectrodes to observe

neuronal activity of the brain, the Penn study, published March 13 in

the journal Science, suggests that neurons in the human substantia

nigra, or SN, play a central role in reward-based learning,

modulating learning based on the discrepancy between the expected and

the realized outcome.

 

This is the first study to directly record neural activity underlying

this learning process in humans, confirming the hypothesized role of

the basal ganglia, which includes the SN, in models of reinforcement

including learning, addiction and other disorders involving

reward-seeking behavior, said lead author Kareem Zaghloul,

postdoctoral fellow in neurosurgery at Penns School off Medicine. By

responding to unexpected financial rewards, these cells encode

information that seems to help participants maximize reward in the

probabilistic learning task.

 

Learning, previously studied in animal models, seems to occur when

dopaminergic neurons, which drive a larger basal ganglia circuit, are

activated in response to unexpected rewards and depressed after the

unexpected omission of reward. Put simply, a lucky win seems to be

retained better than a probable loss.

 

Similar to an economic theory, where efficient markets respond to

unexpected events and expected events have no effect, we found that

the dopaminergic system of the human brain seems to be wired in a

similar rational manner -- tuned to learn whenever anything

unexpected happens but not when things are predictable, " said Michael

J. Kahana, senior author and professor of psychology at Penns School

of Arts and Sciences.

 

Zaghloul worked with Kahana and Gordon Baltuch, associate professor

of neurosurgery, in a unique collaboration among departments of

psychology, neurosurgery and bioengineering. They used microelectrode

recordings obtained during deep brain stimulation surgery of

Parkinsons patients to study neuronal activity in the SN, the

midbrain structure that plays an important role in movement, as well

as reward and addiction. Patients with Parkinsons disease show

impaired learning from both positive and negative feedback in

cognitive tasks due to the degenerative nature of their disease and

the decreased number of dopaminergic neurons.

 

The recordings were analyzed to determine whether responses were

affected by reward expectation. Participants were asked to choose

between red and blue decks of cards presented on a computer screen,

one of which carried a higher probability of yielding a financial

reward than the other. If the draw of a card yielded a reward, a

stack of gold coins was displayed along with an audible ring of a

cash register and a counter showing accumulated virtual earnings. If

the draw did not yield a reward or if no choice was made, the screen

turned blank and participants heard a buzz.

 

This new way to measure dopaminergic neuron activity has helped us

gain a greater understanding of fundamental cognitive activity, " said

Baltuch, director of the Penn Medicine Center for Functional and

Restorative Neurosurgery.

 

Dopamine concentrations will also affect the brain during media

manipulation and propaganda,

covert actions via a corrupt government, deceipt, etc, etc This

seems to explain the populations lethargy (in part) ~ Dr. E

 

 

The work is supported by grants from the National Institutes of

Health, the Conte Center and the Dana Foundation.

 

 

Dr. E

QA & Reg Affairs Unit

<http://qualityassurance.synthasite.com>http://qualityassurance.synthasite.com