ABSTRACT
Sexual homicides (SHs) demand nuanced research for effective prevention, treatment, risk assessment and theoretical insights. Intimate-partner sexual homicides (IPSHs), comprising approximately 20% of SHs, have received limited attention. This study compares IPSHs (n = 56) and non-intimate partner sexual homicides (NIPSHs) (n = 236) in Australia and New Zealand by investigating offender, victim, and crime-scene characteristics. While IPSH perpetrators were typically older, separated, and had prior domestic violence convictions, victims were more often non-white with histories of domestic violence and substance use. Although crime-scene locations and post-offence behaviours differed, similar crime scene behaviours were displayed across offender groups, which seemed to be routed in different underlying motives. Whereas drivers of IPSH commonly were grievance and anger, associated with offences occurring after arguments, drivers for NIPSH were more often sexual deviance and sadism. Overall, IPSH encompasses aspects of domestic violence, homicide, and sexual violence, distinguishing it from SH.
ABSTRACT
The present study examined distinctions between child (n = 30) and adult (n = 212) sexual homicide offenders (SHOs) in Australia and New Zealand, contributing to the limited international research on the subject. Data, primarily sourced from judges' sentencing comments on AustLII and New Zealand Legal Information Institute, revealed significant differences. Child SHOs displayed elevated rates of pedophilia, sexual deviance, and adverse childhood experiences, including sexual abuse. They were more likely to be married, cohabitate, and target familial victims. Their crimes were more often committed during daylight and outdoors, involving tactics such as victim conning, restraints, strangulation, and hiding victim's bodies. No significant group differences emerged regarding offenders' psychopathy or sexual sadism scores. Results were interpreted in line with child SHOs' deviant sexual preferences and the routine activity theory. The study, as the first investigating child sexual homicides in Australia and New Zealand, sets the foundation for an evidence-based approach to policy and practice.
ABSTRACT
The val66met polymorphism of the brain-derived neurotrophic factor (BDNF) gene has been identified as a potential moderator for the relationship between chronic stress and executive functioning. However, whether the presence of the met allele increases cognitive vulnerability or resilience to stress has yet to be determined. Given the established effects of autonomic activity and psychological arousal on executive functioning, in the present study, 56 healthy university students completed self-report measures of chronic stress, positive arousal (vigour) and negative arousal (anxiety) and measured heart-rate variability to quantify autonomic activity. Participants then completed a cognitive test battery that measured attention, decision-making, visual learning and working memory. Regression analyses demonstrated that Val/met participants performed better on attention and working memory tasks than Val/val participants, but no differences were seen in decision-making and visual learning. Further, Val/met participants were protected from stress-related differences in attention seen in Val/val participants. Val66met was not associated with physiological or psychological arousal. This study demonstrates that val66met plays an important but selective role in cognitive performance.
ABSTRACT
The val66met polymorphism of the brain-derived neurotrophic factor gene has been associated with changes in components of executive functioning such as decision making; however, this relationship remains unclear. Val66met-related changes in attention and visual processing speed may explain potential changes in decision making. Furthermore, chronic stress disrupts executive functions and alters autonomic activity. Because the relationship between val66met and cognition has not been investigated in the context of chronic stress or stress-related autonomic changes, in this study 55 healthy university students completed self-report measures of chronic stress and mental health. Participants then completed a virtual reality cognitive test battery (CONVIRT) measuring decision making, attention, and visual processing reaction times. To measure autonomic activity, saliva alpha amylase and heart rate variability (HRV) were assessed at baseline and after CONVIRT testing. Saliva samples were used to identify val66met genotype. Regression analyses demonstrated that val66met was the strongest predictor of decision making and attention, but not visual processing, where valine/methionine (Val/met) participants had faster reaction times than Val/val participants. Val/met participants also had higher perceived chronic stress and heightened increases in sympathetic activity, but not parasympathetic activity. Neither stress nor autonomic activity moderated the effect of val66met on decision making or attention. This study is the first to investigate the role of val66met in decision making, attention, and visual processing while taking into account chronic stress and autonomic activity. This multifactorial approach revealed that carriers of the Val/met genotype may have better decision making and attention than Val/val carriers.
Subject(s)
Attention , Brain-Derived Neurotrophic Factor , Decision Making , Virtual Reality , Brain/metabolism , Brain-Derived Neurotrophic Factor/metabolism , Cognition , Genotype , Humans , Methionine/genetics , Polymorphism, Single NucleotideABSTRACT
New technologies such as virtual reality (VR) and eye-tracking software have paved the way for more sophisticated and ecologically valid measures of cognitive function. Testing the sensitivity and reliability of such measurements in response to acute alcohol intoxication provides a first step in establishing how these measures may operate in relation to cognitive impairments observed post-concussion. Healthy young adults (N = 54, M = 20.65, SD = 2.06, 30 females) completed the CONVIRT test battery (manual simple and choice reaction-time and saccade reaction-time) at three breath alcohol concentration (BrAC) levels: 0.00%T1, 0.05%T2, 0.08%T3. Participants consumed alcoholic beverages at 30-min intervals, with BrAC monitored at 15-min intervals using a breathalyser. All three CONVIRT measures were sensitive to changes in cognitive performance induced by alcohol at BrAC levels at or exceeding 0.05%. A composite measure was also sensitive to alcohol intoxication (Cohen's d = .85 at BrAC = 0.05%; d = 1.20 at BrAC = 0.08%). Strong test-retest reliability was observed (all r < .80), with no gender differences noted. CONVIRT measures were reliable and detected dose-dependent changes in alcohol-induced cognitive impairment. Potentially, the ecologically valid measures may assist in better quantifying the effects of conditions such as concussion, on cognitive performance.
