Kira Bailey

Neural correlates of stimulus and response interference in a 2–1 mapping stroop task

Two sources of interference (i.e., stimulus and response) are believed to contribute to the Stroop interference effect. Some neurophysiological evidence reveals that different neuro-cognitive processes are related to stimulus and response interference in the Stroop and related tasks. However, other evidence indicates that similar patterns of neural recruitment may be associated with these two types interference. Given these discrepant findings, the current study used a 2-1 mapping Stroop task in combination with event-related brain potentials (ERPs) to examine the neural correlates of stimulus and response interference. The response time data revealed that stimulus interference was constant across the response time distribution. In contrast, response interference increased in magnitude across the response time distribution for all but the slowest trials. The stimulus-locked ERP data revealed that early and later modulations of the medial frontal negativity may be sensitive to response interference, but not stimulus interference. These data also revealed that the conflict slow potential (SP) over the parietal and right lateral frontal regions was sensitive to both stimulus and response interference; in contrast, the conflict SP over the left lateral frontal region was only sensitive to response interference. Together the stimulus- and response-locked data lead to the conclusion that the parietal region is primarily involved in response selection in the Stroop task, and that the lateral frontal regions may participate in response monitoring and conflict adaption.

The temporal dynamics of medial and lateral frontal neural activity related to proactive cognitive control

The neural correlates of proactive cognitive control were examined in two experiments using the counting Stroop task and a computerized Blackjack task in combination with event-related brain potentials (ERPs). The primary objective of the study was to determine whether slow wave activity related to proactive control would be observed in the two tasks. Consistent with the existing literature, transient components of the ERPs (i.e., medial frontal negativity and feedback related negativity) were observed over the medial frontal region in both tasks that were related to stimulus congruency and feedback processing, respectively. The medial frontal ERPs in both tasks were modeled with a pair of equivalent current dipoles placed along the anterior to posterior axis of the cingulate. Most importantly, slow wave activity was observed that differentiated incongruent trials from congruent trials after the response in the counting Stroop task, and losses from wins and ties in the Blackjack task. In the Blackjack task, a pair of dipoles in the left lateral frontal and posterior regions modeled the slow wave activity. These data reveal that updating goal representations that support proactive cognitive control may require several 100 ms in contrast to conflict or outcome monitoring that is associated with transient medial frontal neural activity.

The association between chronic exposure to video game violence and affective picture processing: an ERP study

Exposure to video game violence (VGV) is known to result in desensitization to violent material and may alter the processing of positive emotion related to facial expressions. The present study was designed to address three questions: (1) Does the association between VGV and positive emotion extend to stimuli other than faces, (2) is the association between VGV and affective picture processing observed with a single presentation of the stimuli, and (3) is the association between VGV and the response to violent stimuli sensitive to the relevance of emotion for task performance? The data revealed that transient modulations of the event-related potentials (ERPs) related to attentional orienting and sustained modulations of the ERPs related to evaluative processing were sensitive to VGV exposure.

When goals collide: the interaction between prospective memory and task switching.

The neural correlates of prospective retrieval mode, and the basis of the interaction between prospective memory (PM) and task switching, were examined using event-related brain potentials (ERPs). In two experiments individuals performed pure and mixed blocks of trials where they indicated whether or not a word was a noun or a verb or contained one or two vowels based upon a cue that was presented before the target stimulus. Experiment 1 revealed that prospective retrieval mode was associated with slow wave activity over the frontal and posterior regions of the scalp that differed in topography depending upon whether the PM cues were embedded in pure or mixed blocks of trials. This experiment also revealed that the neural correlates of task set configuration, but not cue encoding, were sensitive to PM load. These data indicate that PM load may effect task switching by influencing an individuals ability to maintain multiple task sets in working memory and to efficiently implement a given task set to guide task performance. Additionally, task switching may effect PM by influencing the degree to which individuals rely on stimulus-independent and stimulus-oriented processing to support the realization of delayed intentions.

Signaling a Switch: Neural Correlates of Task Switching Guided by Task Cues and Transition Cues

Event-related brain potentials were used to examine the neural correlates of task switching directed by task cues and transition cues. Task cues signal both a change of task set and the task to implement; in contrast, transition cues signal a change of task set but do not indicate the required task. The data from two experiments revealed that the frontal P2 and reconfiguration slow wave were elicited by task and transition cues and may reflect processes associated with the change detector and task set configuration. Experiment 2 revealed that the frontal positivity and transition parietal slow wave are associated with the retrieval of the prior task set from memory. These data indicate that distinct neural processes that are related to the change detector, task set configuration, and the retrieval of a recently utilized task set from memory support task switching that is guided by task and transition cues.

The effect of music-induced mood on attentional networks

Attention network theory suggests that there are three separate neural networks that execute the discrete functions of alerting, orienting, and executive attention. Previous research on the influence of mood on attention has shown subtle and inconsistent results. The attention network theory may aid in clarifying the influence of mood on attention. The present study investigated the influence of mood on attentional networks in a normal population. Participants performed the Attention Network Test (ANT), which provides functional measures of alerting, orienting, and executive attention. Positive or negative mood was induced by listening to music with a positive or negative valence, respectively; neutral mood was induced by reading a collection of basic facts about China. The results revealed that negative mood led to a significantly higher alerting efficiency relative to other moods, while there were no significant mood effects on orienting or executive attention efficiency. According to the algorithm underlying the ANT, the higher alerting efficiency in the negative mood condition can be attributed to relatively greater benefits of cueing effects. The findings are discussed in the context of the noradrenergic system and of evolutionary significance. Specifically, the increase in the alerting function during negative mood states may be due to the modulation effect of negative mood on the noradrenergic system, and/or to the survival benefit resulting from an increase in automatic vigilance towards negative information. The current results suggest that as the influence of negative mood on attention appears to specifically consist in an enhanced alerting function, it may not be found in studies where the three attentional networks are not dissociated.

An investigation of the neural correlates of attention and effector switching using ERPs

Event-related brain potentials (ERPs) were used to examine the neural correlates of attention and effector switching when one or both types of switches were performed on a given trial. The response time data revealed that switch costs tended to increase from attention switches to effector switches to attention1effector switches. For right-hand responses, attention switching was associated with a parietal slow wave and effector switching was associated with a central readiness potential. For left-hand responses, attention switching was associated with a parietal slow wave, and effector switching was associated with a parietal slow wave and a readiness potential. These data suggest that the independence of the neural systems supporting attention and effector switching may be limited to instances where the dominant hemisphere controls the response.

Did I do that? The association between action video gaming experience and feedback processing in a gambling task

The association between action video game experience and the neural correlates of feedback processing related to positive and negative outcomes was examined in a virtual Blackjack game in combination with event-related brain potentials (ERPs). The behavioral data revealed that the frequency of various outcomes was not related to action gaming experience, indicating that the associations between action gaming experience and the ERP correlates of feedback processing are unlikely to result from variation in motivation or skill related to the Blackjack game between the gamers and non-gamers. The ERP data revealed that action gaming experience was not related to the processing of positive feedback related to wins, or negative feedback for losses that resulted from the joint action of the player and dealer. In contrast, action gaming experience was associated with a reduction in the amplitude of the ERPs elicited by negative feedback wherein the loss resulted from the direct action of the individual (i.e., busts). Together these data may indicate that action gaming is associated with a reduced sensitivity to feedback related to negative outcomes resulting from the direct action of the individual. The association between action video gaming and feedback processing was examined.Neural activity (ERPs) distinguished wins, losses, and busts in the Blackjack task.Action gaming was associated with a reduction in the amplitude of ERPs for busts.Action gaming was not associated with ERPs for wins.