Evidence for the Aetiological theories: Subtle brain structure abnormalities
Neuro-imaging studies have come up with occasionally conflicting findings. However, some fairly consistent findings are:
The functional significance of these findings may be:
- Small or damaged Amygdala is associated with hypo-emotionality; therefore it's possible that an enlarged Amygdala could result in hyper-emotionality
- Prefrontal cortex is involved in regulating emotional responses. Therefore a less active prefrontal cortex may result in emotional pathway overactivity.
(Lopez-Larson et al. Regional prefrontal gray and white matter abnormalities in bipolar disorder. Biologica psychiatry 52(2) 2002)
(Strakowski et al. Brain MRI of structural abnormalities in Bipolar Disorder. Archives general psychiatry (56) 1999)