Neuropsychological predictors of BOLD response during a spatial working memory task in adolescents: what can performance tell us about fMRI response patterns?

The relationship between standardized neuropsychological test performance and functional magnetic resonance imaging (fMRI) response during cognitive tasks is largely unknown. This exploratory investigation examined the relationship between neuropsychological test performance and fMRI response to a spatial working memory (SWM) task among 49 typically developing adolescents. Participants were administered a variety of neuropsychological tests in the domains of working memory, visuospatial skills, executive functioning, attention, learning and memory, visuomotor skills and processing speed, and language functioning. Neuropsychological domain scores were used to predict fMRI response during a SWM task. Results suggest that in many brain regions, neuropsychological performance negatively predicts fMRI response, suggesting that those teens with better neuropsychological abilities required fewer neural resources to adequately perform the task. This study provides further understanding of how neuropsychological abilities relate to neural activity during fMRI tasks, and provides an important link between neuropsychological and fMRI research.

Gender and adolescent alcohol use disorders on BOLD (blood oxygen level dependent) response to spatial working memory.

AIMS: To determine how alcohol use differentially affects brain functioning in male and female adolescents. METHODS: Adolescents with alcohol use disorders (AUDs; 7 female, 11 male) and control adolescents without AUDs (9 female, 12 male), aged 14-17 years, performed spatial working memory and vigilance tasks during functional magnetic resonance imaging. RESULTS: Gender, AUD and their interaction were significantly associated with brain activation patterns to the tasks. There were interactions in the superior frontal, superior temporal, cingulate and fusiform regions, in which female and male adolescents with AUDs showed a different brain response from each other and control subjects. Overall, female adolescents with AUDs showed a greater departure from normal activation patterns than male adolescents with AUD. CONCLUSIONS: Adolescent alcohol involvement may affect male and female brains differently, and adolescent females may be somewhat more vulnerable to adverse alcohol effects. With continued drinking, these adolescents may be at an increased risk for behavioural deficits.

Blood oxygen level dependent response and spatial working memory in adolescents with alcohol use disorders.

BACKGROUND: Previous studies have suggested neural disruption and reorganization in young and older adults with alcohol use disorders (AUD). However, it remains unclear at what age and when in the progression of AUD changes in brain functioning might occur. METHODS: Alcohol use disordered (n = 15) and nonabusing (n = 19) boys and girls aged 15 to 17 were recruited from local high schools. Functional magnetic resonance imaging data were collected after a minimum of 5 days' abstinence as participants performed spatial working memory and simple motor tasks. RESULTS: Adolescents with AUD showed greater brain response to the spatial working memory task in bilateral parietal cortices and diminished response in other regions, including the left precentral gyrus and bilateral cerebellar areas (clusters > or =943 microl; p < 0.05), although groups did not differ on behavioral measures of task performance. No brain response differences were observed during a simple finger-tapping task. The degree of abnormality was greater for teens who reported experiencing more withdrawal or hangover symptoms and who consumed more alcohol. CONCLUSIONS: Adolescents with AUD show abnormalities in brain response to a spatial working memory task, despite adequate performance, suggesting that subtle neuronal reorganization may occur early in the course of AUD.

An FMRI study of response inhibition in youths with a family history of alcoholism.

Disinhibition among alcoholics may precede or result from alcohol use disorders (AUDs). It remains unclear how disinhibition might contribute to AUD risk among youths with a family history of alcoholism (FHP). We used functional magnetic resonance imaging (fMRI) to explore inhibition-related neural risk factors for AUD. Participants were 12- to 14-year-old nondrinkers, including 12 FHP youths and 14 youths with no family history of alcoholism (FHN). Youths performed a go/no-go task during fMRI acquisition. At a conservative threshold, FHN youths showed less inhibitory response than FHP youths in the left middle frontal gyrus, despite similar task performance between groups. Using a more liberal threshold, FHP youths also demonstrated less response in additional frontal regions. These preliminary findings suggest that FHP youths show less inhibitory frontal response than FHN youths. Altered neural activation among FHP youths may underlie subsequent disinhibition and could be related to the AUD risk.