Agression and Traumatic Brain Injury

Frustration Tolerance, Anger and Aggression
Patients who have sustained a TBI have shown a lower tolerance level to frustration, greater degrees of sensitivity to stress and anxiety (Levin et al., 1989), and agitation, defined as constantly uninhibited movement (Reyes, Bhattacharyya, & Heller, 1981). These patients were prone to the expression of anger and if their movements became restricted (Reyes, Bhattacharyya, & Heller, 1981), they became subject to anger or violent behavior when their agitation continued over time (Prigatano et al., 1986).
Lack of Inhibition
As is the case with batterers, lack of inhibition and sudden mood change are often seen in patients with a TBI. (Brooks et al., 1987; Jarvie, 1954). In addition, TBI patients, like batterers, also frequently demonstrate poor social judgment and reduced verbal control (Prigatano, 1991; Struss & Benson, 1986; Lishman, 1978). Frontal lobe deficits lower a person’s ability to self-regulate, and have been hypothesized to be contributing factors to an increase in impulsive behavior (Westby & Ferraro, 1999). Grafman et al. (1996) have proposed that frontal lobe impairment causes higher levels of aggression, associated with reduced impulse and inhibitory control, because rules of social behavior are stored in the frontal lobes. When these areas are stimulated, the result is an inhibition of primitive reactions. If brain impairment has blocked access to this information, inappropriate kinds of social behavior, such as physically and verbally aggressive behavior may emerge in confrontational situations. Grafman et al. (1996) found that TBI patients scored higher on anger and hostility measures than the control group.

Perseveration
Perseveration is an abnormal repetition of specific behaviors that may include movements and verbalizations, and may be observed on drawings, sorting tests, and tracking tests. Perseverative behavior is an indication of frontal lobe impairment, and frequently occurs in individuals that engage in aggressive behaviors (Sedek et al., 1993). An example of common perseveration behavior would be to continue engaging in the same activity to solve a task even when the external variables have changed, resulting in unsuccessful outcomes. These kinds of situations can lead to feelings of helplessness and frustration (Sedek et al., 1993).