Biological explanations of phobias

Genetic factors: 

A01: family studies: Research shows that having a family member with a phobic disorder increases the risk that an individual develops a similar disorder. Family member who already has the disorder is called a proband. 

A02:

 + Support comes from Fyer et al: found that proband has 3 times as many relatives who also experienced phobias as normal controls. This shows that the role of genes plays a cause and development of phobias. 

+ Solyom et al found: 45% of phobic patients had at least one relative with the disorder compared to a rate of 17% of non-phobic controls. Ost also found that 64% of blood phobics has at least one relative with the same disorder. This also supports the idea that there is a genetic link to phobias and also supports the view that individuals develop the same disorder as their probands. 

- However, 17% of the non-phobic controls in Solyom's study could of had a phobia, but have yet not been diagnosed.