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There has been a great deal of interest in understanding how the human brain processes appetitive food cues, and knowing how such cues elicit craving responses is particularly relevant when current eating behavior trends within Westernized societies are considered. One substance that holds a special place with regard to food preference is chocolate, and studies that used functional magnetic resonance imaging (fMRI) and event-related potentials (ERPs) have identified neural regions and electrical signatures that are elicited by chocolate cue presentations. This review will examine fMRI and ERP findings from studies that used high-caloric food and chocolate cues as stimuli, with a focus on responses observed in samples of healthy participants, as opposed to those with eating-related pathology. The utility of using high-caloric and chocolate stimuli as a means of understanding the human reward system will also be highlighted, as these findings may be particularly important for understanding processes related to pathological overeating and addiction to illicit substances. Finally, research from our own lab that focused on chocolate stimulus processing in chocolate cravers and non-cravers will be discussed, as the approach used may help bridge fMRI and ERP findings so that a more complete understanding of appetitive stimulus processing in the temporal and spatial domains may be established.

Behavioral and electrophysiological correlates of attentional bias to cannabis-related cues were investigated in a marijuana dependent group and a non-user group employing a drug Stroop task in which cannabis-related, negative and neutral images were presented. Behaviorally, cannabis users were less accurate during drug-containing blocks than non-users. Electrophysiologically, in chronic marijuana-users, an early positive ERP enhancement over left frontal scalp (EAP, 200-350ms) was present in response to drug-containing blocks relative to negative blocks. This effect was absent in the non-user group. Furthermore, drug-containing blocks gave rise to enhanced voltage of a posterior P300 (300-400ms), and a posterior sustained slow wave (LPP, 400-700ms) relative to negative blocks. However, such effects were similar between cannabis users and non-users. Brain source imaging in cannabis users revealed a generator for the EAP effect to drug stimuli in left ventromedial prefrontal cortex/medial orbitofrontal cortex, a region active in fMRI studies of drug cue-reactivity and a target of the core dopaminergic mesolimbic pathway involved in the processing of substances of abuse. This study identifies the timing and brain localization of an ERP correlate of early attentional capture to drug-related pictures in chronic marijuana users. The EAP to drug cues may identify a new electrophysiological marker with clinical implications for predicting abstinence versus relapse or to evaluate treatment interventions.

Background The negative effect of hypoxia on cognitive function has been well described. However, less has been published regarding cognitive dysfunction resulting from hypoxia produced by exposure to different altitudes. Methods We measured short-term and working memory capacity (Digit Span tasks), cognitive flexibility and selective attention (Word-Color Stroop Task), and executive functioning (Trailmaking A and B tests) at baseline and simulated altitudes equal to 17,500 ft (5334 m) and 25,000 ft (7620 m) in order to obtain more information about the role of altitude exposure on cognitive tasks important for optimal functioning in the aviation environment. Results Behavioral observations indicated that hypoxia was induced at different simulated altitudes. Marked declines in cognitive performance were also observed for all tests at 25,000 ft, with scores indicating greater impairment in this condition relative to others. Subjects also showed greater impairment when scores obtained in the 17,500-ft condition were compared to baseline, although the effects were not as clearly defined relative to the 25,000 vs. baseline contrasts. Discussion The results of this study suggest that electronic versions of these tests may be useful in screening for acute symptoms of hypoxia and could provide insight into how discrete cognitive processes become impaired with oxygen deprivation at various altitudes. Given that these tests also assess neuropsychological functioning, our results allow for inferences to be made about the effects of hypoxia on human brain functioning.

Diminished emotional capacity is a core characteristic of psychopathic personality. We examined behavioral and electrophysiological differences in attentional bias to emotional material in 34 healt ...

Cannabis users respond to cannabis-related cues in ways that differ from nonusers, and scientists have employed a variety of research methodologies to study cannabis cue-reactivity. Using behavioral techniques, cannabis users have been shown to afford greater attentional bias toward cannabis cues and increased craving for the substance is also observed after these cues are presented. Electrophysiology research suggests that cannabis users process cannabis cues differently than nonusers and that these differences can be observed very early after stimulus presentations [ie, 200 milliseconds (ms) and onward]. Finally, functional magnetic resonance imaging research has shown that neural regions involved in reward processing become activated for cannabis users when they see cannabis-related cues. Findings obtained with these methodologies appear to support one another and may provide clinicians with a means of identifying those who are at a high risk for prolonged and/or severe cannabis abuse.

Anecdotal evidence and qualitative research attest to the importance of work–family interactions pre-, during and post-missions. This study uses thematic content analysis to quantify characteristics of work–family interactions and how these changed by stage of cosmonauts’ career, identifying the effect of space career variables (e.g., time in space and station) on such interactions during and post-career. Using a thematic scoring scheme developed for this study, we coded work–family interactions identified from interviews with 20 retired male cosmonauts. The majority of work–family interactions were ones in which work overlapped into family life and work hindered or interfered with the family situation. The most common resolution was that family adjusted to work, and the mood or tone about this outcome was almost equally divided among negative, positive and neutral. Changes in work–family interactions and their resolution over the cosmonaut’s life showed that the significant interactions were most evident during the cosmonaut career. Although the cosmonaut career has high work demands, it did adjust for family when the need arose. The Russian Space Agency (RKS) eased the impact of the periodic absences, especially through regular communication sessions. Positive work–family interactions, i.e., work or family helping the opposite role, were more likely for those who had been on ISS, not Mir, and for those whose last flight was after 2000. Our data reflect retired cosmonauts’ recollections of work–family interactions during their career. Examples of work overlapping into family life and work viewed as interfering with family life were possibly more salient or better remembered than work or family helping the other role.

Cigarette smoking is still quite prevalent despite public education campaigns, and more understanding about the processes that relate to relapse and abstinence is still needed. In the current study, recent abstinent smokers who were later deemed to be relapsers or abstainers responded to the color of smoking-related and neutral words in a Smoking Stroop Task while high-density EEG was recorded. One-month Abstinent smokers responded more slowly to smoking words relative to control participants who had never smoked, while Relapsers did not show this effect. One-month relapsers displayed greater voltage of the late positive potential (400-600 ms, aLPP) over the left frontal scalp relative to both one-month abstinent smokers and never smokers. Our findings suggest that smoking cues are more salient for abstinent smokers who are prone to relapse, and this ERP activity evoked by cigarette cues may be a potential biomarker for relapse susceptibility. In contrast, successful abstainers may respond to smoking cues by engaging top-down cognitive control mechanisms leading to less aLPP voltage but greater RT interference. This appears to be the first ERP study to use a Smoking Stroop Task and a high-density electrode array to characterize the spatiotemporal dynamics of smoking-related cue reactivity in abstinent smokers who successfully abstained for one month and those who later relapsed within the same period.

The spatiotemporal dynamics of the hedonic response to chocolate images was investigated in healthy participants high and low in trait-chocolate craving employing high-density ERPs. There were two sessions: (1) before and (2) after satiety for chocolate. Among cravers, chocolate stimuli evoked a positive amplitude ERP enhancement over the anterior frontal scalp (250–350 ms) that was not modified by satiety and that source localized to the left lateral orbitofrontal cortex. Chocolate stimuli also elicited a later LPP over the posterior scalp (360–560 ms) which was of similar amplitude for high and low chocolate cravers, independent of satiety. Unexpectedly, in non-cravers, chocolate stimuli elicited an earlier (100–250 ms) negative ERP modulation over the frontomedial scalp, which disappeared after eating chocolate to satiety. These results confirm the role of OFC in unrestrained appetitive responses to chocolate in cravers, and suggest top-down influences from cognitive control mechanisms when attempting to restrain the urge to eat chocolate in non-cravers.