Sylco Hoppenbrouwers agrees: «As a consequence
of our research, some very influential theories that assign prominent roles to
fearlessness in the aetiology
of psychopathy will need to be reconsidered and made consistent with current neuroscientific
evidence.
Psychological characteristics include low IQ, impulsivity, hyperactivity, lack
of empathy, and
fearlessness.12, 13 Parental risks include low levels
of education, antisocial behavior, poor parenting skills, maternal early onset
of childbearing, and family discord.14 — 20 There is
evidence of an intergenerational transmission
of these problems through both genetic and environmental channels.18, 19,21 — 24 Developmental research also shows that the spontaneous onset
of physical aggression in school - aged children is highly unusual.1, 7,25 Instead, the developmental precursors
of chronic physical aggression are present before school entry.