Mental Health - Area 2 Flashcards
What does the biochemical principle focus on ?
Focusses on abnormal levels of neurotransmitters.
What are excitatory neurotransmitters ?
Causes the next neurone to be activated (over stimulated)
What are inhibitory neurotransmitters ?
Prevents action of the next neurone.
What does the monoamine hypothesis of depression state ?
Proposes that depression is caused by levels of monoamines, a group of neurotransmitters.
What neurotransmitters does monoamines include ?
Serotonin, dopamine and noradrenaline (in hippocampus and hypothalamus responsible for heart rate.
What was Meyer’s study in 2006 ?
Studied 17 patients with depression, who had not taken antidepressants for 5 months and used PET scan to compare with 17 clinically normal patients.
What did Meyers (2006) find ?
Found that depressed patients had significantly higher levels of monoamine oxidase in all 11 brain regions. (Causes monoamines to brake down too quickly).
What does the dopamine hypothesis of schizophrenia state ?
States that an excess of dopamine at limbic system causes schizophrenia.
The revised hypothesis is that there is an excess of dopamine at D2 receptors.
What are positive symptoms of schizophrenia linked with ?
Linked with hypo function (too much dopamine activity) in mesolimbic pathway, which is responsible fore motivation, emotion and reward.
What are negative symptoms of schizophrenia linked with ?
Linked with erratic dopamine function in mesocortical pathway, which is responsible for executive function.
What did Seeman (1987) study ?
Looks at several stands of evidence that provides support for dopamine hypothesis.
What did Seeman (1987) find ?
-Drugs increase levels of dopamine increase symptoms of schizophrenia.
-Antipsychotics reduce schizophrenia symptoms.
-Post mortem of schizophrenia brains have increased density of D2 receptors than normal patients.
What is GABA ?
They are important inhibitory neurotransmitters in CNS. They switch off next neurone, reducing activity.
What is GABA responsible for in biochemical explanation of mental health ?
Counterbalances glutamate neurotransmitters. People with phobias have decreased levels of GABA so neurone in glutamate pathway is increased leading to anxiety.
What did Panda et al (1999) look at ?
Assigned 69 patients with social phobia, where they took a drug that increased levels of GABA for 14 weeks and gave control group placebo.
What did Panda et al (1999) find ?
Found significantly lower symptoms in GABA group, suggesting that increased levels of GABA can lead to a reduction in anxiety.
What does the brain abnormality of depression state ?
States that Limbic system shows differences in amount of grey matter and levels of activity in the brain (amygdala and hippocampus).
What does brain abnormality of depression in amygdala state ?
Increased activity in amygdala when depressed patients were presented with a negative stimuli. However, there was reduced activity when depressed patients were presented with a positive stimuli.
What does brain abnormality of depression in hippocampus state ?
Hippocampus is significantly smaller in patients with depression (reduced by 20%). The more severe the depression, the more severe the loss of grey matter in the hippocampus.
What did Sheline (2001) study in terms of amygdala ?
Gave FMRI scans to 11 depressed patients and 11 control patients.
What did Sheline (2001) find in terms of amygdala ?
Found that amygdala was more active in patients with depression that control group during resting and activity when shown emotional images expressing fear.