Biological Explanation to Depression

Question 1

Biological factors involved in diagnosing depression

Answer 1

Genes
Biochemistry
Brain structure

Question 2

Wender et al

Answer 2

Studied biological relatives of adopted people who had been diagnosed with severe depression and found that they were 8x more likely to have depression than the non-depressed control group

Question 3

Harrington et al

Answer 3

People with depression have a 20% chance to have another depressed relative compared to 10% chance for the general population

Question 4

Mc Guffin

Answer 4

177 twins with depression. Found a 46% concordance for MZ twins and 20% for DZ

Question 5

Serotonin theory of depression

Answer 5

Serotonin is a neurotransmitter that is linked with depression, low levels are found in depressed individuals.
It is suggested that serotonin production is normal in a depressed patient however when serotonin is moving from nerve to nerve a depressed patient has an overactive presynaptic neuron. This presynaptic neuron deactivates the secretin in and then reuptakes it, meaning the secrets in doesn’t get passed on, leading to depression.

Question 6

McNeal and Cimbolic

Answer 6

Measured the cerebrospinal fluid of people with depression. Found there was much lower levels of tryptophan, a bi-product of serotonin, in the spinal fluids of depressed patients.

Question 7

Zhang

Answer 7

Found the 5-HTT gene, linked to serotonin deficiencies, is 3x more common in depressed patients than non-depressed patients

Question 8

Teuting

Answer 8

Found there were lower levels of tryptophan in the urine of depressed patients compared to the non depressed control

Question 9

Strengths of serotonin theory

Answer 9

• Implications, SSRIs
• McNeal and Cimbolic
• Zhang
• Teuting

Question 10

Weaknesses of serotonin theory

Answer 10

• Overly narrow and ignores psychological factors
• Reductionist as it reduces complex disease to a neurotransmitter
• Tianeptine works at treating depression, however, this reduces levels of serotonin

Question 11

Drewets et al

Answer 11

Used fMRI scans toscan the brains of depressed patients and non depressed controls and found the depressed patients had a smaller hippocampi and basal ganglia than the control.

Question 12

Strengths of biological approach to depression

Answer 12

Harrington et al
McGuffin
Zhang
Practical implications
Removes blame

Question 13

Weaknesses of biological approach to depression

Answer 13

Genetic studies difficult to run without environmental influence
Determanistic
Reductionist
Treatments have side effects