Brain Response and Reaction Time in Natural and Comfort Conditions, with Energy-Saving Potential in an Office Environment

Psychological adaptation to ambient temperatures is fascinating and critical, both theoretically and practically, for energy efficiency in temperate climates. In this study, we investigated and compared the brain response (event-related potentials with a late positive component and latency ~300 milliseconds; labeled “P300” in the present study) and reaction times of Indonesian participants (n = 11), as tropical natives living in Japan, and Japanese participants (n = 9) in natural (i.e., hot during the summer and cold during the winter) and comfort conditions (with cooling and heating). Thermal comfort under contrasting conditions was studied using both instruments and subjective ratings. P300 potential and reaction time were measured before and after a Uchida–Kraepelin (U–K) test (30 summation lines). The results showed that P300 potential and latency did not change between the pre- and post-U–K test among conditions in any of the groups. Furthermore, Indonesian participants showed lower P300 potential (hot conditions) and slower P300 latency (hot and cooling conditions) than Japanese participants. We also found that the reaction time of the Indonesian group significantly differed between the pre- and post-U–K test in an air-conditioned environment, with either cooling or heating. In this study, Indonesian participants demonstrated a resistance to P300 and worse reaction times during work in a thermally unfamiliar season, specifically indicated by the indifferent performances among contrasting environmental conditions. Indonesian participants also showed similar thermal and comfort sensations to Japanese participants among the conditions. In the winter, when the Indonesian neutral temperature is higher than Japanese’s, the energy consumption may increase.

Where is the money? Dynamics in feedback processing and attention during spatial probabilistic learning

Learned feature-based stimulus-reward-associations can modulate behavior and the underlying neural processing of information. In our study, we investigated the neurocognitive mechanisms underlying learning of spatial stimulus-reward-associations. Participants performed a probabilistic spatial reward-learning task that required participants, within 40 trials, to learn which out of four locations on a computer screen yielded the most gain-feedback when chosen. Our behavioral findings show that participants learned to choose which location was most rewarding. Those findings were paralleled by significant amplitude differences in event-related potentials (ERPs) elicited by the presentation of loss and gain feedback; the amplitude of the feedback-related negativity (FRN) was more negative in response to loss feedback compared to gain feedback, but showed no modulation by trial-number. On the other hand, the late positive component (LPC), became larger in response to losses as the learning-set progressed, but smaller in response to gains. Additionally, immediately following feedback presentation, brain activity in the visual cortex - read out through alpha frequency oscillations measured over occipital sites - was predictive of the amplitude of the N2pc ERP component, a marker of spatial attention orienting, observed on the next trial. Taken together, we elucidated neurocognitive dynamics underlying feedback processing in spatial reward learning, and the subsequent effects that spatial stimulus-reward association learning have on spatial attention.

Neural correlates of pride and joy recognition in early childhood

I investigated neural processing during the recognition of pride and joy in early childhood using the event-related potential (ERP) technique. Electroencephalography recording was taken of 21 children aged between 4 and 6 years. They were shown photographs of familiar peers and strangers whose facial expressions displayed the emotion of either pride or joy. ERPs were recorded for the children's judgment of the expression of these two emotions when an image was presented. The results demonstrate that the neural dynamics during children's recognition of pride and joy involve three stages: The early negative component is spontaneously responsive to familiar faces, the midlatency negative central component is responsive to expression of familiar faces, and the late positive component marks greater extended processing of an expression of pride. These findings provide new insight into the neural mechanism of pride and joy recognition in children aged 4 to 6 years.

Electrophysiological markers of fairness and selfishness revealed by a combination of Dictator and Ultimatum Games

In the framework of neuroeconomics, Event Related Potentials (ERPs) were recorded during a combination of a Dictator Game (DG), in which the participants always played the role of Allocators, and an Ultimatum Game (UG), in which the participants always played the role of Responders. Behavioral analysis showed that the majority of participants were characterized by very low levels of altruistic decision making, which included two homogenous groups of individuals, one expressing fairness (GrpF, about 26%) and one selfish behavior (GrpS, about 20%). In the analysis of both games, an early negativity (N1) in the fronto-central cortical sites distinguished the GrpF and GrpS participants. The subsequent P2 wave component appeared more associated with the characteristics of the stimulus than with its behavioral value. During UG, we observed that a medial frontal negativity (MFN) occurred earlier and with greater amplitude in GrpS than in GrpF, which depended to a large extent to a spiteful punishment when the Responder refused offers less favorable for himself. The late positive component (LPC) of ERP recorded in posterior-parietal cortical sites was evoked earlier and with greater amplitude during UG than in DG and, in both games, LPC was evoked earlier and with greater amplitude in GrpS than in GrpF. Our results bring new evidence to the existence of different circuits activated by the evaluation of fair and unfair proposals in participants characterized by different expressions of perceived fairness, thus suggesting that particular brain dynamics could be associated with moral decisions.

Sleep’s short-term memory preservation and long-term affect depotentiation effect in emotional memory consolidation: Behavioral and EEG evidence

Study Objectives Sleep plays a pivotal role in the off-line processing of emotional memory. However, much remains unknown for its immediate vs. long-term influences. We employed behavioral and electrophysiological measures to investigate the short- and long-term impacts of sleep vs. sleep deprivation on emotional memory. Methods Fifty-nine participants incidentally learned 60 negative and 60 neutral pictures in the evening and were randomly assigned to either sleep or sleep deprivation conditions. We measured memory recognition and subjective affective ratings in 12- and 60-hour post-encoding tests, with EEGs in the delayed test. Results In a 12-hour post-encoding test, compared to sleep deprivation, sleep equally preserved both negative and neutral memory, and their affective tones. In the 60-hour post-encoding test, negative and neutral memories declined significantly in the sleep group, with attenuated emotional responses to negative memories over time. Furthermore, two groups showed spatial-temporally distinguishable ERPs at delayed test: while both groups showed the old-new frontal negativity (300-500 ms, FN400), sleep-deprived participants additionally showed an old-new parietal, Late Positive Component effect (600-1000 ms, LPC). Multivariate whole-brain ERPs analyses further suggested that sleep prioritized neural representation of emotion over memory processing, while they were less distinguishable in the sleep deprivation group. Conclusions These data suggested that sleep's impact on emotional memory and affective responses is time-dependent: sleep preserved memories and affective tones in the short term, while ameliorating affective tones in the long term. Univariate and multivariate EEG analyses revealed different neurocognitive processing of remote, emotional memories between sleep and sleep deprivation groups.

Narrative Review: Quantitative EEG in Disorders of Consciousness

In this narrative review, we focus on the role of quantitative EEG technology in the diagnosis and prognosis of patients with unresponsive wakefulness syndrome and minimally conscious state. This paper is divided into two main parts, i.e., diagnosis and prognosis, each consisting of three subsections, namely, (i) resting-state EEG, including spectral power, functional connectivity, dynamic functional connectivity, graph theory, microstates and nonlinear measurements, (ii) sleep patterns, including rapid eye movement (REM) sleep, slow-wave sleep and sleep spindles and (iii) evoked potentials, including the P300, mismatch negativity, the N100, the N400 late positive component and others. Finally, we summarize our findings and conclude that QEEG is a useful tool when it comes to defining the diagnosis and prognosis of DOC patients.

Increased Neural Efficiency in Visual Word Recognition: Evidence from Alterations in Event-Related Potentials and Multiscale Entropy

Visual word recognition is a relatively effortless process, but recent research suggests the system involved is malleable, with evidence of increases in behavioural efficiency after prolonged lexical decision task (LDT) performance. However, the extent of neural changes has yet to be characterized in this context. The neural changes that occur could be related to a shift from initially effortful performance that is supported by control-related processing, to efficient task performance that is supported by domain-specific processing. To investigate this, we replicated the British Lexicon Project, and had participants complete 16 h of LDT over several days. We recorded electroencephalography (EEG) at three intervals to track neural change during LDT performance and assessed event-related potentials and brain signal complexity. We found that response times decreased during LDT performance, and there was evidence of neural change through N170, P200, N400, and late positive component (LPC) amplitudes across the EEG sessions, which suggested a shift from control-related to domain-specific processing. We also found widespread complexity decreases alongside localized increases, suggesting that processing became more efficient with specific increases in processing flexibility. Together, these findings suggest that neural processing becomes more efficient and optimized to support prolonged LDT performance.

Novel Adjective Processing in Preschool Children: Evidence From Event-Related Brain Potentials

Purpose Recent findings in preschool children indicated novel adjective recall was enhanced when learned using repeated retrieval with contextual reinstatement (RRCR) compared to repeated study (RS). Recall was similar for learned pictures used during training and new (generalized) pictures with the same adjective features. The current study compared the effects of learning method and learned/generalized pictures on the neural processes mediating the recognition of novel adjectives. Method Twenty typically developing children aged 4;6–5;11 (years;months) learned four novel adjectives, two using RRCR and two using RS. Five-minute and 1-week tests assessed adjective recall using learned and generalized pictures. Also, at the 1-week visit, event-related potentials (ERPs) were recorded to assess children's processing of learned/generalized pictures, followed by naturally spoken novel adjectives in a match–mismatch paradigm. Results Naming recall and match–mismatch judgment accuracy were similar for the RS and RRCR conditions and across learned/generalized pictures. However, ERPs revealed more reliable condition effects in the phonological mapping negativity, indexing phonological expectations, and the late positive component, indexing semantic reanalysis, for the adjectives learned in the RRCR relative to the RS condition. Unfamiliar pictures (generalized) elicited larger amplitude N300 and N400 components relative to learned pictures. Conclusions Although behavioral accuracy measures suggest similar effects of the RS and RRCR learning conditions, subtle differences in the ERPs underlying novel adjective processing indicate advantages of RRCR for phonological processing and semantic reanalysis. While children readily generalized the novel adjectives, ERPs revealed greater cognitive resources for processing unfamiliar compared to learned pictures of the novel adjective characteristics. Supplemental Material https://doi.org/10.23641/asha.13683214

Context-based interpersonal relationship modulates social comparison between outcomes: an event-related potential study

Social comparison is a common behavior that largely determines people’s experience of decision outcome. Previous research has showed that interpersonal relationship plays a pivotal role in social comparison. In the current study, we investigated whether the manipulation of context-based relationship would affect participants’ comparison of self-outcome and other-outcome. Participants first finished a trust game with likeable (dislikeable) partner and then they were involved in a gambling task and observed the outcomes for themselves and for partners. According to self-reports, participants were more satisfied with likeable partner’s gains than losses only when they received gains, but they were always more satisfied with dislikeable player’s losses compared to gains. Event-related potentials including the feedback-related negativity (FRN), P3 and late positive component (LPC) were sensitive to context-based relationship. Specifically, the prediction error signal (indexed by the FRN) was largest when participants received losses but dislikeable player received gains. Meanwhile, the P3 indicates that participants had stronger motivation to outperform dislikeable player. Finally, the LPC was larger when participants received the same outcomes with dislikeable players. In general, our results support the key point of the self-evaluation maintenance model that personal closeness modulates subjective sensitivity when drawing a comparison of one’s outcomes with other’s outcomes.

Eye region as a predictor of holistic facial aesthetic judgment: An eventrelated potential study

Event-related potentials (ERP) play an important role in the early detection of emotional arousal. Previous studies of aesthetics have shown that the positive component appearing around 200 ms after stimulus (P2) and the larger late positive component (LPC) are closely related to the early stage of aesthetic judgment. We investigated the temporal features of facial aesthetic judgment on the basis of facial features by using the ERP technique. Participants were instructed to predict holistic face aesthetic level based on the regions of eyes, mouth, or nose. Behavioral results show that holistic score predictions based on the eye region were no different to holistic aesthetic ratings. The ERP analysis results show that beautiful eyes and faces elicited a smaller P2 amplitude and LPC amplitude when judging the holistic aesthetic. The P2 effect of facial aesthetics may reflect automatic processing of facial aesthetics and the difference in LPC may be related to motivational attention to facial aesthetics. Because of the similar ERP effect between the holistic facial aesthetic judgment and the aesthetic judgment of eye region, this region may play a significant role in predicting holistic facial aesthetics. The implication is that the eyes are not only a window to the soul, but also a benchmark of beauty.