Psychology 9-1 GCSE - 

6.1.2 - Understand biological explanations of criminality, including personality types (Eysenck, 1964), to include strengths and weaknesses of the theory:

a) Extraversion - 

This is associated with traits such as sociability, talkativeness and excitability. 

b) Introversion - 

A preference for quiet settings and being alone, the opposite of extraversion.

c) Neuroticism - 

A tendency towards anxiety, self doubt, depression and shyness and other negative feelings.

d) Psychoticism - 

Aggression, impulsitivity, aloofness and antisocial behavior.