12.2.1 Attack And Escape Behaviours 2 Flashcards
Many studies have found ___________ in people with a history of violent behaviour, including people convicted of arson and other violent crimes and people who attempt suicide by violent means.
low serotonin turnover
Follow-up studies on people released from prison have found that those with lower serotonin turnover had a ____ probability of further convictions for violent crimes.
greater
The effects are not sufficiently powerful that we could use blood tests to make important decisions about individuals, such as which prisoners should be eligible for ____.
parole
The results of low serotonin turnover are less clear for aggressive behaviour in the ____ ____ (where extreme violence is uncommon).
normal population
It is possible to alter serotonin synthesis by changes in ____. Neurons synthesise serotonin from tryptophan, an amino acid found in small amounts in proteins.
diet
____ crosses the blood-brain barrier by an active transport channel that it shares with phenylalanine and other large amino acids. Thus, a diet high in other amino acids impairs the brains ability to synthesise serotonin.
Tryptophan
Considering these results, it would seem prudent for anyone with aggressive or suicidal tendencies to reduce consumption of aspartame (NutraSweet, which is 50% ____) and maize (American corn), which is high in ____ and low tryptophan.
phenylalanine
Much of the variation in serotonin activity, and therefore violence, relates to ____.
genetics
People vary in the gene that controls ____ ____, the enzyme that converts tryptophan into serotonin. People with less active forms of this enzyme are more likely than average to report frequent anger and aggression.
tryptophan hydroxylase
When researchers have used drugs or diet to ____ serotonin levels, some people felt depressed, others became more aggressive or impulsive, and those with previous drug problems reported a craving for drugs.
suppress
Serotonin’s role is not specific to aggression. A better hypothesis is it high levels of serotonin ____ a variety of impulses, and low levels remove inhibitions.
inhibit
Although most studies imply that serotonin inhibits aggressive behaviour, the brain releases serotonin ____ aggressive behaviour. Apparently, a low level of serotonin activity prior to aggression magnifies the response when serotonin is suddenly released at the start of an aggressive encounter.
during
Both experiences and genetics modify activity in the ____, one of the main areas for regulating anxiety.
amygdala
The response to an unexpected loud noise, known as the ____ ____, is extremely fast. Auditory information goes 1st to the cochlea nucleus in the medulla and from there directly to an area in the pons that commands tensing the muscles, especially the neck muscles.
startle reflex
Tensing the neck muscles is important because it neck so ____ to injury.
vulnerable