Discuss and evaluate two theories that explain the causes of major depressive
disorder (MDD)
One theory that attempts to explain the cause of major depressive disorder (MDD) is
the theory proposed by the biological view. This view puts forward the idea that biological
factors contribute towards the causation of mental disorders such as MDD. Potential factors
that are proposed are genetics, hormones, and brain anatomy.
Genetic theory of MDD is that sufferers of MDD inherit a specific predisposition to
develop the disorder from a parent who either suffers from the condition or is a carrier of the
gene (McGuffin, 2014). Evidence for that there is a genetic component to the causation
comes from family studies and specifically twin studies. Family studies are able to show that
people diagnosed with MDD are likely to have relatives to also be suffering with depression,
Myrna et al (2005) showed such in a study in which they showed that children with
depressed grandparents were much more likely to also be diagnosed with MDD than those
without as 59% of the children with the relation developed such. This shows to how there is
indeed a genetic cause that is responsible for MDD, this is further supported by the work
done with twins.
Adoptive twin studies are able to demonstrate whether a condition is a result of
biology or environment due to twins sharing the same DNA, but the twins are brought up in
differing environments. Monozygotic twins have been shown to have 46% to develop MDD
(McGuffin, 1996) which shows to how that despite being raised in different environments,
this demonstrates to how there is a biological role behind the causation of the disorder as
both children are still predisposed to developing MDD. To add to this Levison & Nichols
(2014) after conducting an adoptive twin study themselves, it was found that there is a
disorder (MDD)
One theory that attempts to explain the cause of major depressive disorder (MDD) is
the theory proposed by the biological view. This view puts forward the idea that biological
factors contribute towards the causation of mental disorders such as MDD. Potential factors
that are proposed are genetics, hormones, and brain anatomy.
Genetic theory of MDD is that sufferers of MDD inherit a specific predisposition to
develop the disorder from a parent who either suffers from the condition or is a carrier of the
gene (McGuffin, 2014). Evidence for that there is a genetic component to the causation
comes from family studies and specifically twin studies. Family studies are able to show that
people diagnosed with MDD are likely to have relatives to also be suffering with depression,
Myrna et al (2005) showed such in a study in which they showed that children with
depressed grandparents were much more likely to also be diagnosed with MDD than those
without as 59% of the children with the relation developed such. This shows to how there is
indeed a genetic cause that is responsible for MDD, this is further supported by the work
done with twins.
Adoptive twin studies are able to demonstrate whether a condition is a result of
biology or environment due to twins sharing the same DNA, but the twins are brought up in
differing environments. Monozygotic twins have been shown to have 46% to develop MDD
(McGuffin, 1996) which shows to how that despite being raised in different environments,
this demonstrates to how there is a biological role behind the causation of the disorder as
both children are still predisposed to developing MDD. To add to this Levison & Nichols
(2014) after conducting an adoptive twin study themselves, it was found that there is a
