Disorders of Emotion

1. Kluver-Bucy Syndrome

It is rare in humans and occurs only when there is bilateral amygdala damage. It results in diminished fears, overeating, oral fixation, heightened sex drive, and visual agnosia. 

2. Autism

A neurological developmental disorder with the following characteristics: impaired social interaction, communication problems, and stereotyped behaviors. It is usually diagnosed before the age of 3, and there is a gender ratio of 5 boys to 1 girl. 

Many studies have proposed neurological differences in children with Autism. Studies have explored the possibilities of larger head sizes and thus larger brain volumes, increased white matter volume with decreased gray matter volume, decreased cerebellar size, larger amygdalae, larger hippocampi, or smaller thalamus and corpus callosum.

One recent, large-scale study done by Haar Berman and Dinstein (2014). They had concluded, "while anatomical abnormalities may be present in distinct subgroups of ASD individuals, the current finds show that many previously reported anatomical measures are likely to be of low clinical and scientific significance for understanding ASD neuropathology as a whole." 

Mirror neurons are specialized neurons found in premotor and somatosensory cortex that fire when other people perform actions. They are thought to be important in learning new skills from others, including emotional skills. It has been suggested that this system may be impaired in individuals with ASD. Hamilton (2013) found little evidence of this.

Whatever the neuropathology of ASD, individuals with the condition do have emotional differences. They can be aggressive, have difficulty understanding the emotions of others (emotional agnosia), and difficulty reading the facial expressions and intonation of others. There must be some macro-or microscopic brain difference that underlies these emotional differences.

3. Lability

An involuntary display of emotion that sometimes is a result of neuropathology. Disruptions in prefrontal cortex and limbic system connections may lead to limbic system being under regulated by the prefrontal cortex. Some patients may display sudden outbursts of laughing or crying. Patients report these episodes are distressing and socially disabling.