Depression-biological explanation

Question 1

what is the biological explanation of Depression?

Answer 1

the monoamine hypothesis

Question 2

what does the biological explanation of Depression state?

Answer 2

the imbalance of monoamines (neurotransmitters) in the brain causes depression

Question 3

what do the imbalance of neurotransmitters affect?

Answer 3

they affect the signals particularly the dopamine and serotonin pathways

Question 4

what are the functions of the dopamine pathway? (5)

Answer 4

-reward (motivation)
-pleasure/euphoria
-motor function
-compulsion
perseveration

Question 5

what are the functions of the serotonin pathway? (5)

Answer 5

• mood
• memory
• processing
• sleep
• cognition

Question 6

what’s the role of serotonin in relation to depression? (2)

Answer 6

controls the activity of other neurotransmitters
-regulates sleep, mood, and appetite
low serotonin=low levels of noradrenaline & dopamine

Question 7

what’s the role of Noradrenaline in relation to depression? (4)

Answer 7

responsible for: 
-alertness
-energy
attention to life
anxiety/lack of it 
low levels= drowsiness,lethargy,problems with concentration

Question 8

what’s the role of dopamine in relation to depression?

Answer 8

responsible for:
-ability to pay attention
-motivation
-feel pleasure
-get a sense of accomplishment
low levels dopamine= low concentration, low motivation, and lack the feel pleasure

Question 9

what is the effect of too much reuptake of Serotonin?

Answer 9

has the functional effect of lowering their levels

Question 10

what is monoamine oxidase?

Answer 10

an enzyme that breaks down monoamines

Question 11

what is the problem with monoamine oxidase?

Answer 11

it breaks down monamines meaning you have less of them

Question 12

how is a quick way to tell that you are depressed?

Answer 12

a by-product of the action of the monoamine oxidase (norepinephrine and serotonin will be present in their blood and urine

Question 13

what supporting evidence is there for monoamine oxidase?

Answer 13

-Rosen et al (1981)- compared substances found in the urine of depressed patient and control group-compounds produced as a by-product as norepinephrine and serotonin in large amounts in the depressed person

Question 14

what’s scientifically good about this explanation?

Answer 14

empirical and objective

Question 15

what supporting evidence is there for the monoamine hypothesis? (2)

Answer 15

• Drevets et al (1999)- found reduced serotonin receptor-binding potential in unmedicated depressed patients
• Versiani et al (1999)-found patients who had noradrenaline reuptake inhibitors increased mood

Question 16

what’s a problem with most of the evidence?

Answer 16

most evidence for abnormal levels of chemicals in the brain being a cause of depression is correlational so we can’t know if change in chemicals cause unipolar depression or the other way round (no cause and effect)

Question 17

what other explanations of depression are there?

Answer 17

the cognitive explanation

Question 18

who found medication didn’t make depression worse?

Answer 18

Delgado (2000)- found that monoamine depletion did not make symptoms worse in depressed patients not taking medication