Psychological dysfunction within an individual associated with distress or impairment in functioning and a response that is not typical or culturally expected
The systematic evaluation and measurement of psychological, biological, and social factors in an individual presenting with a possible psychological disorder
Genetic mechanisms that ultimately contribute to the underlying problems causing the symptoms and difficulties experienced by people with psychological disorders
Those people who reported more severe stressful life events and had at least one short allele of the 5-HTT gene were at greater risk of developing depression (Caspi et al., 2003) (serotonin-transporter gene)
When serotonin (norepinephrine) levels are low, other neurotransmitters are permitted to range more widely, become dysregulated, and contribute to mood irregularities
When rats or other animals encounter conditions over which they have no control, they give up attempting to cope and seem to develop the animal equivalent of depression