“I feel that this constant demand for respect
makes a great many people privately very resentful. Why should respect
be extracted from us, for any and every religion, or any and every
culture? It amounts to a statutory requirement of hypocrisy.”
(Minette Marin, Times)
///////////////////////////////////////////
Serotonin Link To Impulsivity, Decision-making, Confirmed
ScienceDaily (June 11, 2008)
— New research by scientists at the University of Cambridge suggests
that the neurotransmitter serotonin, which acts as a chemical messenger
between nerve cells, plays a critical role in regulating emotions such
as aggression during social decision-making.
Serotonin has long been associated with social behaviour, but its
precise involvement in impulsive aggression has been controversial.
Though many have hypothesised the link between serotonin and
impulsivity, this is one of the first studies to show a causal link
between the two.
Their findings highlight why some of us may become combative or
aggressive when we haven't eaten. The essential amino acid necessary
for the body to create serotonin can only be obtained through diet.
Therefore, our serotonin levels naturally decline when we don't eat, an
effect the researchers took advantage of in their experimental
technique.
The research also provides insight into clinical disorders
characterised by low serotonin levels, such as depression and obsessive
compulsive disorder (OCD), and may help explain some of the social
difficulties associated with these disorders.
This research, funded by the Wellcome Trust and the Medical Research
Council, suggests that patients with depression and anxiety disorders
may benefit from therapies that teach them strategies for regulating
emotions during decision making, particularly in social scenarios.
The researchers were able reduce brain serotonin levels in healthy
volunteers for a short time by manipulating their diet. They used a
situation known as the 'Ultimatum Game' to investigate how individuals
with low serotonin react to what they perceive as unfair behaviour. In
this game one player proposes a way to split a sum of money with a
partner. If the partner accepts, both players are paid accordingly. But
if he rejects the offer, neither player is paid.
Normally, people tend to reject about half of all offers less than
20-30% of the total stake, despite the fact that this means they
receive nothing - but rejection rates increased to more than 80% after
serotonin reductions. Other measures showed that the volunteers with
serotonin depletion were not simply depressed or hypersensitive to lost
rewards.
PhD student Molly Crockett, a Gates Scholar at the University of
Cambridge Behavioural and Clinical Neuroscience Institute, said: "Our
results suggest that serotonin plays a critical role in social
decision-making by normally keeping aggressive social responses in
check. Changes in diet and stress cause our serotonin levels to
fluctuate naturally, so it's important to understand how this might
affect our everyday decision-making."
Where do we get Serotonin?
The only way to get the raw material for serotonin (tryptophan) is
through the diet. Therefore, serotonin levels are lower when you
haven't eaten, an effect that the researchers take advantage of in
their experimental technique. Eating tryptophan rich foods like poultry
(chicken soup) and chocolate can boost serotonin levels - some have
speculated that this is why these are "feel good" foods.
