AROUSAL-RELATED P3a TO NOVEL AUDITORY STIMULI IS ABOLISHED BY A MODERATELY LOW ALCOHOL DOSE

Abstract

Concurrent measures of event-related potentials (ERPs) and skin conductance responses were obtained in an auditory oddball task consisting of rare target, rare non-signal unique novel and frequent standard tones. Twelve right-handed male social drinkers participated in all four cells of the balanced placebo design in which effects of beverage and instructions as to the beverage content (expectancy) were independently manipulated. The beverage contained either juice only, or vodka mixed with juice in the ratio that successfully disguised the taste of alcohol and raised average peak blood-alcohol level to 0.045% (45 mg/dl). ERPs were sensitive to adverse effects of mild inebriation, whereas behavioural measures were not affected. Alcohol ingestion reliably increased N2 amplitude and reduced the late positive complex (LPC). A large, fronto-central P3a (280 ms latency) was recorded to novel sounds in the placebo condition, but only on the trials that also evoked electrodermal-orienting responses. Both novel and target stimuli evoked a posterior P3b (340 ms), which was independent of orienting. Alcohol selectively attenuated the P3a to novel sounds on trials with autonomic arousal. This evidence confirms the previously suggested distinction between the subcomponents of the LPC: P3a may be a central index of orienting to novel, task-irrelevant but potentially significant stimuli and is an important component of the arousal system. P3b does not have a clear relationship with arousal and may embody voluntary cognitive processing of rare task-related stimuli. Overall, these results indicate that alcohol affects multiple brain systems concerned with arousal, attentional processes and cognitive-autonomic integration.

Selectively attending to natural scenes after alcohol consumption: An ERP analysis

“…In addition to early, perceptual-related ERP components, we were interested in the assessment of the P3, the late post-perceptual ERP component. In line with previous findings (OscarBerman, 1987;Polich and Kok, 1995;Marinkovic et al, 2001;Bartholow et al, 2003), it was predicted that P3 amplitude is reduced under alcohol intoxication compared to the placebo control condition. Furthermore, it was predicted that alcohol intoxication also has an impact on overt behavior responses as reflected by slower reaction times and increased error rates.…”

“…However, alcohol effects may also be delineated at the level of specific cognitive subsystems and processes (cf., . For instance, recent studies provide strong evidence for selective alcohol impairments at post-perceptual stages of information processing (OscarBerman, 1987;Polich and Kok, 1995;Marinkovic et al, 2001;Bartholow et al, 2003). Pursuing the goal of examining the effects of alcohol in relation to specific cognitive subsystems, the present study examined the fundamental capability of stimulus categorization.…”

Responses of Human Anterior Cingulate Cortex Microdomains to Error Detection, Conflict Monitoring, Stimulus-Response Mapping, Familiarity,andOrienting

“…Words were presented for 240 ms, and SOA was 2000 ms. (4) Auditory oddball: subjects pressed a key to rarely occurring target tones (76; 10.5%) embedded in a series of frequently occurring standard tones (571; 79%) and nontarget novel tones (76; 10.5%) requiring no response. All stimuli were 70 ms in duration, presented every 1.8 s. Each nontarget novel sound was a unique sound differing in pitch and harmonics but with the same amplitude envelope as the pure tones serving as frequents and targets (Marinkovic et al, 2001). (5) Color-cued conditional letter discrimination (cued conditional RT): subjects were presented with a color cue for 210 ms ("red" or "green").…”

“…The P3a, elicited by novel stimuli, evokes an involuntary reorientation of attention as well as a constellation of autonomic features including a prominent electrodermal response (Marinkovic et al, 2001). Such features may be mediated by ACC projections directly to brainstem autonomic efferent structures, and ACC stimulation can provoke autonomic and general changes in cortical tonus (Devinsky et al, 1995).…”

Survey of alcohol-related presentations to Australasian emergency departments

“…as the blood alcohol level increases, cognitive function and psychomotor • performance decrease rapidly (Easdon et al 2005); consumption of less than two standard drinks potentially results in effects that increase risk of injury (Tagawa et al 2000;Howland et al 2001;Marinkovic et al 2001;Marinkovic et al 2004;Moulton et al 2005;Breitmeier et al 2007) and driving ability is impaired at blood alcohol levels of about 0.05 per cent, a level reached after two or three standard drinks (Tagawa et al 2000) national health and medic al research council | 55 australian guidelines to reduce health risks from drinking alcohol…”