'Critically consider the view that depression has psychological origins.'
There has been much research into the psychological causes of depression from many different perspectives. These however do not create a whole picture if biological explanations are subsequently disregarded. Biological causes seem to lack full explanation and support in terms of scientific research and some of the theories and notions seem to be contradictory.
Depression certainly does seem to run in families. The concordance rates for unipolar depression are significant and those for bipolar are extremely high (40% and 72% respectively in MZ twins). This suggests that genetics play a significant role in levels of inherited susceptibility. The real problem does not lie so much with separating nature and nurture as with our limited understanding of the nature of genes themselves.