Chapter 6 Trait theories (2 branches = biological and psychological)
∆ Trait theories: these approaches look at the combination of biological or psychological attributes that might
explain criminology. Trait theorists focus on basic human drives linked to antisocial behaviour – aggression,
violence, and impulsivity
∆ Soma type: an idea used in a system developed for categorized people on the basis of their body build, associated
with the work of William Sheldon.
∆ Sociobiology: the branch of science that views human behaviour as motivated by inborn biological desires and
urges. The urge to survive and reproduce motivates human behaviour
o They want to make sure of their survival and that of others to make sure of survival
∆ Modern biological trait theorists believe that physical, environmental, and social conditions work together to
produce human behaviour
o Environmental forces trigger antisocial behaviour in people biologically predisposed to deviance, or if
conditions are right, mediate or offset the effects of biological predisposition
∆ Bio criminologists believe that vitamins and nutrients are needed for normal brain functioning, especially
throughout the early years of life.
∆ Sugar and crime: Another suspected nutritional influence on behaviour is a diet especially high in carbohydrates
and sugar. High sugar intake levels have been associated with attention span deficiencies.
∆ Hypoglycemia: A biochemical condition, in this case a deficiency of sugar, which influences antisocial behaviour
and criminality. When the brain is deprived of blood sugar it has no alternative food supply to call on and its
metabolism slows down.
∆ Hormonal influences: Hormones, enzymes, and neurotransmitters, are the keys to understanding human behaviour
and that they explain gender differences in the crime rate
o Androgens: male sex hormones, which have been linked to criminality
o Testosterone: an androgen, which controls secondary sex characteristics and can alter behaviour
∆ Premenstrual syndrome: The biogenetic theory that several days prior to and during menstruation, females are
best by irritability and poor judgment as result of hormonal changes. Placing them at a greater risk for criminality
o Can cause aggressive and antisocial behaviour
∆ Allergies: are excessive reactions of the body to foreign substances. Neuroallergies affect the nervous system and
are believed to produce enzymes that cause swelling of the brain and sensitivity in the central nervous system,
which are linked to mental, emotional, and behavioural problems
∆ Environmental contaminants: dangerous quantities of copper, cadmium, mercury, and inorganic gases, such as
chlorine, in the ecosystem influence behaviour and are linked to emotional and behavioural disorders, severe
illness, or even death
∆ Some criminologists looking at brain activity (neurophysiology: the study of brain activity that looks at
neurological and physical abnormalities acquired during the fetal or prenatal stage, which are thought to control
behaviour) believe abnormalities acquired as early as the fetal stage may control behaviour throughout life
∆ Electroencephalograph (EEG): a device that can record the electronic impulses given off by the brain, commonly
called brainwaves. Violent criminals have higher levels of abnormal EEG recordings than non-criminals
∆ Fetal Alcohol syndrome (FAS): Occurs when children in the womb are exposed to alcohol and later experience
developmental delays and often displays crime-related behaviour
o Those with FASD can also have ADHD and are more likely to engage in disruptive school experiences.
Poor impulse control, learning abilities, speech problems, and unable to see consequences are effects
∆ Minimal brain dysfunction: an abnormality in the cerebral structure that causes maladaptive behaviour and is
linked to antisocial acts and imbalance in urge-control
∆ ADHD: child shows a developmentally inappropriate lack of attention, impulsivity and hyperactivity.
∆ Persistent criminality has been linked to dysfunction in the frontal and temporal regions of the brain, which
regulate and inhibit human behaviour
∆ Tumors, injury and disease: Has been linked to psychological problems including personality changes,
hallucinations, and psychotic episodes. People with tumors are more likely to be depressed, have temper
outbursts, are irritable, and even homicidal attacks
∆ Brain chemistry and crime: abnormal levels of some neurotransmitters including androgens, dopamine,
norepinephrine, serotonin, monoamine, oxidase, and GABA, have been linked with aggression.
∆ Arousal theory: the view that people with a high arousal level seek powerful stimuli to maintain an optimal level
seek powerful stimuli to maintain an primal level of arousal; associated with violence, aggression, and sociopathy