Exam 2 Flashcards
Three hypothesis for the brain and agression
Different behaviors (aggression, feeding, sexual behavior) may be in unique and separate brain areas but that these areas are not yet outlined due to poor technology.
Different behaviors are NOT in segregated and dedicated areas of the brain. They are in the same area(s) of the brain, but have a differential activation pattern across the areas of the brain.
There are both dedicated (and separate) brain areas for the different brain areas for some of the different behavior, but there may also be overlapping areas of the brain for these behavior that have a differential activation pattern.
1994 finding of head injuries in following samples
Male spouse abusers—51%
Non-violent maritally-discordant men—25%
Maritally-satisfied men—16%
Meta-analysis
a statistical summary across several previous studies
“Somatic marker”
right ventromedial prefrontal cortex lesions result in deficits because of an inability to recruit emotionally salient information when making decisions with some uncertain outcome, producing a tendency to favor immediate rewards.
Reduced amygdala volume is associated with development of
Trait aggression
Antisociality
Sensation-seeking
Violence
Studies also find that the frontal cortex and orbitofrontal cortex are
important for the regulation of violence and aggression.
Intimate partner violence
(“any physical, sexual, or psychological harm occurring between current or former intimate partners”
Traumatic Brain Injury
a resulting injury that results from a violent blow or jolt to the head or body or from an object penetrating the skull.
Finding from 1989
61.3% of partner violence perpetrators had closed head injuries.
1994 finding of head injuries in following samples
Male spouse abusers—51%
Non-violent maritally-discordant men—25%
Maritally-satisfied men—16%
A second 1994 finding
found no differences in IPV between a sample with head injuries and a sample with orthopedic injuries (spine, joint, and muscle injuries). But head injured men reported more loss of temper and control, more verbal communication difficulties, arguing with others, and more verbal abuse versus the orthopedically injured men
A 2012 meta-analysis
found 53.6% of IPV had TBI as compared to the general population of 38.5% of men
One study suggests that the severity of TBI
greater is men who engage in IPV than men with TBI who do not engage in IPV.
Common complaints from caregivers of those with TBI
Agitation Frustration Restlessness (which when treated with physical or chemical restraints makes the TBI patient more frustrated) Moderate of severe “aggressiveness” from TBI patient to the caretaker Fatigue* Slowness* Forgetfulness* Increasingly severe tempter outbursts* Anxiety* Self-centerednes
One 2006 study found
25% of moderate to severe TBI show aggression at 6, 24, and 60 month post-injury
One 2007 study found
that 88% of male and female prisoners in one sample had at least one head injury in the past.
Another meta-analysis found that
among all types of male offenders, the estimated prevalence of TBI was 64.4%”
Executive functioning deficits
may the mechanism by which violence occurs after TBI
Lesion studies
“Lesions often result in confirmed loss of vocal (specific) regions” (p. 325) and are thus more severe than head-injuries.
Lesions in the following brain areas are associated with anger, irritability, and violence
Dorsolateral prefrontal cortex
Ventromedial prefrontal cortex
Right ventromedial prefrontal cortex
Orbitofrontal cortex
Medial frontal cortex
Temporal lobes
OMPCC
orbital/medial prefrontal cortex circuit
IED
Intermittent Explosive Disorder (a psychological disorder characterized by impulsive aggression
Studies have found the following with IED (which suggest lesion to OMPCC)
Impaired decision making
Impaired facial emotion recognition
Impaired odor identification
Other studies have shown IED patients have a negative bias towards neutral emotional faces
One limitation of this review
is that they did not look at functional changes
Future studies should address the following:
ongitudinal assessment and study of acute head injury
Gender differences in TBI and brain lesions
The authors urge that clinicians and emergency responders identify head injuries as they are “both and effect and cause of violence and abuse.” (p. 329)
“As there is evidence that anger management programs following TBI are effective in reducing both trait and state anger, proper screening and referral can be effective in reducing violent behavior for individuals with brain injury.” (p. 329)
