Sex differences in impulsivity and brain morphometry in methamphetamine users

There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

Abstract

Methamphetamine (METH) is an addictive stimulant, and METH users have abnormal brain structures and function. The aims of this study were to investigate the relationships between impulsivity, brain structures, and possible sex-specific differences between METH users and non-drug using Controls. Structural MRI and the Barratt Impulsiveness Scale (BIS) questionnaire were completed in 124 subjects: 62 METH (ages 41.2 ± 1.4 years, 34 males) and 62 Controls (ages 43.3 ± 2.3 years, 36 males). Independent and interactive effects of METH use status and sex were evaluated. Relationships between METH usage characteristics, brain morphometry, and impulsivity scores were examined. METH users had higher impulsivity scores, on both the Cognitive and Behavioral Factors from the BIS ( p < 0.0001–0.0001). Compared with same-sex Controls, male METH users had larger, while female METH users had smaller, right superior frontal cortex (interaction- p = 0.0005). The male METH users with larger frontal volumes and female METH users with smaller or thinner frontal cortices had greater Cognitive impulsivity (interaction- p ≤ 0.05). Only female METH users showed relatively larger nucleus accumbens (interaction- p = 0.03). Greater impulsivity and thinner frontal cortices in METH users are validated. Larger superior frontal cortex in male METH users with greater cognitive impulsivity suggest decreased dendritic pruning during adolescence might have contributed to their impulsive and drug use behaviors. In the female METH users, smaller frontal cortices and the associated greater impulsivity suggest greater neurotoxicity to these brain regions, while their relatively larger nucleus accumbens suggest an estrogen-mediated neuroprotective glial response. Men and women may be affected differently by METH use.

Related collections

Most cited references 41

Record: found
Abstract: not found
Article: not found

Automatically Parcellating the Human Cerebral Cortex

B Fischl (2004)

0 comments Cited 456 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

Age at first alcohol use: a risk factor for the development of alcohol disorders.

D DeWit, E M Adlaf, D R Offord … (2000)

This study aimed to describe the natural course of DSM-III-R alcohol disorders as a function of age at first alcohol use and to investigate the influence of early use as a risk factor for progression to the development of alcohol disorders, exclusive of the effect of confounding influences. Data were obtained from a community sample (N=5,856) of lifetime drinkers participating in the 1990-1991 Mental Health Supplement of the Ontario Health Survey. Survival analyses revealed a rapid progression to alcohol-related harm among those who reported having their first drink at ages 11-14. After 10 years, 13.5% of the subjects who began to drink at ages 11 and 12 met the criteria for a diagnosis of alcohol abuse, and 15.9% had a diagnosis of dependence. Rates for subjects who began to drink at ages 13 and 14 were 13.7% and 9.0%, respectively. In contrast, rates for those who started drinking at ages 19 and older were 2.0% and 1.0%. Unexpectedly, a delay in progression to harm was observed for the youngest drinkers (ages 10 and under). Hazard regression analyses revealed a nonlinear effect of age at first alcohol use, marked by an elevated risk of developing disorders among subjects first using alcohol at ages 11-14. First use of alcohol at ages 11-14 greatly heightens the risk of progression to the development of alcohol disorders and therefore is a reasonable target for intervention strategies that seek to delay first use as a means of averting problems later in life.

0 comments Cited 216 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

Increased activation in the right insula during risk-taking decision making is related to harm avoidance and neuroticism.

Martin Paulus, Corianne Rogalsky, Alan H. Simmons … (2003)

Decision making and risk taking are interrelated processes that are important for daily functioning. The somatic marker hypothesis has provided a conceptual basis for processes involved in risk-taking decision making and has been used to link discrete neural substrates to risk-related behaviors. This investigation examined the hypothesis that the degree of risk-taking is related to the degree of activation in the insular cortex. Seventeen healthy, right-handed subjects performed a risk-taking decision-making task during functional magnetic resonance imaging (fMRI) using a fast event-related design. This investigation yielded three main findings. First, right insula (BA 13) activation was significantly stronger when subjects selected a "risky" response versus selecting a "safe" response. Second, the degree of insula activation was related to the probability of selecting a "safe" response following a punished response. Third, the degree of insula activation was related to the subjects' degree of harm avoidance and neuroticism as measured by the TCI and NEO personality questionnaires, respectively. These results are consistent with the hypothesis that insula activation serves as a critical neural substrate to instantiate aversive somatic markers that guide risk-taking decision-making behavior.