Positive affect is generally associated with improvements in cognitive abilities; however, few studies have addressed positive affect and its relation to specific cognitive control processes. Previous research suggests positive affect conditions are more flexible/distractible states, suggesting cognitive control processes are perhaps decreased in context maintenance and increased in conflict detection/resolution. To measure the cognitive control processes, specific components of the scalp-recorded event-related potentials (ERPs) called the cue slow wave (context maintenance), the N450 (conflict detection), and conflict SP (conflict resolution) were acquired in response to an affective single-trial, cued-Stroop task. Participants were presented with pleasant, neutral, and unpleasant images prior to Stroop instruction (i.e., respond to "color" or "word") and response. Participants had greater accuracy during the pleasant condition when given a longer delay for extra time to process the high conflict task, t(36) = 3.09, p = .004, 95% CI (0.07, 0.02) compared to the unpleasant condition. Additionally, the unpleasant condition resulted in greater context maintenance than pleasant (increased cue-related slow wave amplitude; t(40) = 2.38, p = .02). Unpleasant conditions were associated with greater conflict resolution processes (as measured by the conflict SP) with high conflict trials, t(40) = 2.55, p = .015; whereas pleasant did in congruent trials, t(40) = 2.707, p = .010. Findings suggest negative affective states increase participants' focus on the task in avoidance of the distracting unpleasant picture. Our findings lay the foundation for understanding the differences between state and trait affect on cognitive control processes.

PURPOSE: This study examined the effect of different intensities of acute exercise on attention allocation to visual food cues, postexercise energy intake, and subjective measures of hunger in women. METHODS: This crossover study utilized treatment conditions that were randomized and counter-balanced. Fifty-two adult women, 18-29 years, were compared under three separate conditions: no exercise, 45 min of moderate-intensity exercise at 3.9 METs and 22.5 min of vigorous-intensity exercise at 7.8 METs. To measure attention allocation to visual food cues, participants were shown a passive viewing task consisting of a continual stream of pictures of food (high and low calorie) and nonfood stimuli while brain activity was monitored using an EEG. The late positive potential (LPP) component of the scalp-recorded event-related potential (ERP) was used for data analysis. Postexercise food intake was measured during an ad libitum snack offered at the end of each condition. Subjective ratings of appetite were measured before and immediately after each condition using a visual analog scale (VAS). RESULTS: No significant differences for LPP were found for the condition (no exercise, moderate exercise or vigorous exercise) by picture type (high calorie, low calorie or nonfood) interaction (P = 0.184). Total kcal intake did not differ among the different exercise conditions (P = 0.19). However, even though energy intake did not differ among exercise conditions, low-energy-dense foods were consumed at higher rates compared to high-energy-dense foods after the vigorous (P = 0.0005) and moderate exercise conditions (P = 0.02) compared to the nonexercise condition. Findings from the VAS indicate the moderate exercise session resulted in significantly higher ratings of hunger when compared to the nonexercise (P = 0.04) and vigorous exercise sessions (P = 0.0046). There was also a significant condition (no exercise, moderate exercise or vigorous exercise) by period (pre- or postexercise) interaction found in postexercise ratings of hunger (P = 0.018). The moderate exercise condition reported higher levels of hunger after exercise (P = 0.0002). In addition, findings from the VAS also indicated energy for the moderate exercise condition increased postexercise (P = 0.006) and was higher than either the nonexercise (P = 0.011) or the vigorous exercise conditions (P = 0.017). CONCLUSION: The results of this study demonstrate that an acute bout of moderate exercise may increase subjective hunger and overall energy without increasing the neural response to visual food cues or postexercise energy intake. Furthermore, it also shows that an acute bout of vigorous exercise did not alter neural response to visual food cues, hunger or energy intake postexercise.

Literature has examined the cognitive processes that underlie user evaluation of target websites, apps and information systems (WIS). In general, the studies have found that the consciously reasoning evaluation of a specific WIS¡¦ usefulness and enjoyment can effectively predict the usage that WIS. However, in the trend of consumerzing WIS, users are more likely than before to evaluate WIS by impression, meaning that users browse and appraise multiple novel WISs simultaneously and can pay little attention to each of them. To investigate the impression formation process, the current study develops hypotheses based on social neuroscience literature of emotional processing. This study further captures the transient process of impression formation with the event-related potential (ERP, or the brain wave pattern) methodology. Two ERP experiments were conducted. In the first experiment, 24 subjects made evaluations (like vs. dislike) toward novel website logos that were presented with 200 milliseconds (ms). The results show that, as early as 120 ms after logo appearance, the ERP starts to differentiate between liked and disliked logos. In the second experiment, 18 subjects made enjoyment and usefulness evaluations toward novel logos that were presented with 1 second. The behavior data of the second experiment show that for novel logos, enjoyment and usefulness evaluation scores are correlated. ERP data further indicated that information of both enjoyment and usefulness dimensions are inevitably noticed and processed. These findings suggest that, for WIS, the process of evaluation by impression formation might be different from that by reasoning. The impression formation process might be characterized by the activation of spontaneous emotion and by the interdependence between the enjoyment and usefulness evaluations.

Event-related potentials were recorded as subjects were presented with pairs of words, one word at a time, to examine the electrocortical manifestations of association formation and the effect of intra-list semantic similarity. Two types of lists were presented: Same – all pairs belonged to the same semantic category; Different – all pairs belonged to a different semantic category. Subjects were told to memorize the pairs for a following paired associate recall test. Recall was better for the Different than Same lists. Subsequent recall was predicted by the amplitudes of a potential lasting throughout the epoch and the P555 to each word of a pair (likely reflecting state- and item-related encoding activity, respectively), as well as a late positive wave that occurred after the offset of the second word, which is thought to reflect association formation. A larger N425 was elicited by pairs in the Different than Same lists, likely reflecting semantic integration.

The ability to recognise an individual's affective state from their facial expression is crucial to human social interaction. However, understanding of facial expression recognition processes is limited because mounting evidence has revealed important differences between posed and genuine facial expressions of emotion. Most previous studies of facial expression recognition have used only posed or simulated facial expressions as stimuli, but posed expressions do not reflect underlying affective state unlike genuine expressions. The current study compared behavioural responses and Evoked Response Potentials (ERPs) to neutral expressions, posed smiles and genuine smiles, during three different tasks. In the first task, no behavioural judgment was required, whereas participants were required to judge whether the person was showing happiness in the second task or feeling happiness in the third task. Behavioural results indicated that participants exhibited a high degree of sensitivity in detecting the emotional state of expressions. Genuine smiles were usually labelled as both showing and feeling happiness, but posed smiles were far less likely to be labelled as feeling happiness than as showing happiness. Analysis of P1 and N170 components, and later orbitofrontal activity, revealed differential activity levels in response to neutral expressions as compared to posed and genuine smiles. This differential activity occurred as early as 135ms at occipital locations and from 450ms at orbitofrontal locations. There were significant interactions between participant behavioural sensitivity to emotional state and P1 and N170 amplitudes. However, no significant difference in ERP activity between posed smiles and genuine smiles was observed until 850ms at orbitofrontal locations. An additional finding was greater right temporal and left orbitofrontal activation suggesting hemispheric asymmetry of facial expression processing systems.

Adaptive decision making depends on multiple processes, including fast and efficient processing of stimulus events for effective responding and slow trial-to-trial learning of action values for optimization of the selection process. I applied the event-related brain potential (ERP) technique to investigate the involvement of two neuromodulatory systems in learning and decision making: The locus coeruleus-norepinephrine (LC-NE) system and the mesencephalic dopamine system (DA system). I present evidence that the "oddball" N2, a negative deflection in the ERP elicited by task-relevant events that begins approximately 200 ms after onset of the eliciting stimulus and that is sensitive to low-probability events, is a manifestation of cortex-wide noradrenergic modulation recruited to facilitate the processing of unexpected stimuli. Further, Holroyd and Coles (2002) proposed that the impact of DA reinforcement learning signals on the anterior cingulate cortex (ACC) produces a component of the ERP called the feedback-related negativity (FRN). I present electroencephalographic evidence that both the DA system and the LC-NE system act in concert when learning from rewards that vary in expectedness, but that the DA system is relatively more exercised when subjects are highly engaged/challenged by learning tasks, whereas the impact of the LC-NE system is attenuated by this manipulation. / Graduate

Current research in stuttering suggests that individuals who stutter (IWS) may have a hyperactive error-monitoring system, leading to the exacerbation and anticipation of verbal dysfluencies. Using a neurophysiological marker of error processing known as the feedback error-related negativity, the current thesis involved three studies. First, a pilot study was conducted to ensure that word feedback cues were usable in the current paradigm. Second, a classic virtual T-maze task was used to assess the generic error processing mechanism of IWS. Third, an adaptation of the T-maze was used to assess the integrity of the reinforcement learning system of IWS and their ability to associate reward and error information of personalized problem words with predictive cues. Results suggest preliminary evidence for functional generic error processing in IWS and disrupted error processing when conditioned predictive cues are needed to predict fluent versus dysfluent outcomes. / Graduate

Event-related potentials were recorded as subjects were presented with pairs of words, one word at a time, to examine the electrocortical manifestations of association formation and the effect of intra-list semantic similarity. Two types of lists were presented: Same – all pairs belonged to the same semantic category; Different – all pairs belonged to a different semantic category. Subjects were told to memorize the pairs for a following paired associate recall test. Recall was better for the Different than Same lists. Subsequent recall was predicted by the amplitudes of a potential lasting throughout the epoch and the P555 to each word of a pair (likely reflecting state- and item-related encoding activity, respectively), as well as a late positive wave that occurred after the offset of the second word, which is thought to reflect association formation. A larger N425 was elicited by pairs in the Different than Same lists, likely reflecting semantic integration.

Neural correlates of consciousness (NCCs) represent the physiological processes related to consciousness and awareness. Consciousness is theorized as a recurrent process of integration between separate but specialized brain areas. Previous research has used electroencephalography (EEG) to locate NCCs of sensory awareness in vision through event-related potentials (ERPs). Two ERP components thought to represent visual awareness are the visual awareness negativity (VAN) and late positivity (LP). VAN and LP have been extensively studied, yet little research has been conducted in other sensory modalities. In this study, the presence of an auditory awareness negativity (AAN) and associated LP is investigated in 23 subjects using EEG. To avoid false positives in data analysis, two research hypotheses were preregistered. The results indicate that auditory LP does occur, but that AAN does not, in hypothesized intervals. However, the data suggest that AAN may occur at a later interval. Possible attributes of the later interval are discussed. In sum, the data provide results consistent with recurrent theories of sensory awareness.

Auditiv mismatch negativity (MMN) är en neurologisk hjärnrespons som visar hur känslig hjärnan är för auditiva förändringar. Perceptuell load teorin argumenterar att krävande visuella sökuppgifter eliminerar auditiva distraktorer från att bearbetas i arbetsminnet. Syftet är att observera event-related potential (ERP) händelser för att se om avvikande ljud exkluderas under hög visuell belastning. Ett korsmodalt uppmärksamhetstest utfördes där deltagarna (N = 26) fick utföra en visuell sökuppgift med två svårighetsgrader samtidigt som de skulle ignorera tonfrekvenser som spelades upp i bakgrunden. Resultatet visade auditiv MMN-respons under både låg och hög visuell belastning. Det fanns ingen tydlig skillnad på MMN mellan låg och hög belastning. Hörselcortex registrerade en avvikande ton i oddball och att samma ton fanns i kontroll-upplägget. Argument för att distraktorer bearbetas under kontrollerad uppmärksamhet. Ytterligare studier med större stickprov och olika ljudfrekvenser, naturliga och icke naturliga, krävs för att se hur ljuden påverkar bearbetningsprocessen.