Although some people suffering from HD may remain even tempered, others may lose the ability to control their emotions. Emotional volatility may be evident in increased irritability or episodes of explosiveness.

A study on mice with the HD allele of the Huntington gene found that mice portrayed abnormal social behavior, particularly chronic aggressive behavior.

For others, rigidity of thinking causes the individual to focus on one particular request. This individual may become irritable, frustrated or aggressive if demands are not met. To read more about the study on mice with the HD allele, click here.

When the caudate nucleus has deteriorated, emotions are improperly regulated, causing an increase in feelings of frustration and irritability. These feelings are often legitimate and triggered by something in the environment.