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Abstract: Though the humans are more susceptible to unpleasant stimuli of higher intensity, how the valence intensity of unpleasant stimuli impacts subsequent cognitive processing, and whether this impact increases with the unpleasantness, require clarification. For this purpose, event-related potentials (ERPs) were recorded for highly negative (HN), mildly negative (MN) and neutral cueing pictures, and subsequently for the non-emotional target picture while subjects were required to discriminate the location of the target. Cue-induced ERPs showed more negative deflections for the HN than for the neutral pictures in the 450–650ms time interval. The emotion effect for the MN cueing stimuli, however, was non-significant in this interval. In contrast, target-induced P3 amplitudes were significantly more negative following MN versus neutral cueing pictures, while the P3 amplitudes were not significantly different between HN and neutral conditions, irrespective of cueing validity. Thus, despite weak immediate impact, MN stimuli influenced subsequent target processing more heavily than HN stimuli. This suggests that the impact of unpleasant events on cognition doesn''t necessarily increase with the unpleasantness. Mild unpleasant stimulus, which is weak in immediate emotion arousal, should not be neglected due to the likelihood of producing a sustained impact. [Copyright &y& Elsevier]

Abstract: The present study investigated neural correlates underlying the psychological processing of the extent of self-relevance. Event-related potentials were recorded for distracting names different in extent of self-relevance while subjects performed a three-stimulus oddball task. The results showed larger amplitudes and prolonged latencies for high self-relevant than for moderate self-relevant, low self-relevant and non-self-relevant names at P2 component. Furthermore, N2 amplitudes were decreased for the high self-relevant and moderate self-relevant names than for the low self-relevant and non-self-relevant names. Moreover, the high self-relevant names elicited larger positive deflections than the moderate self-relevant names which, in turn, elicited larger positive deflections than the low self-relevant and non-self-relevant names at both P3 and 440–540ms intervals. Additionally, the peak latencies of P3 were prolonged during the high self-relevant and moderate self-relevant than during the low self-relevant and non-self-relevant conditions. Therefore, in addition to replicating the classic self-relevant effect, the present study extended previous studies by showing a clear self-relevant degree effect, with high self-relevant stimuli processed more preferentially in the brain relative to those low in self-relevance. [Copyright &y& Elsevier]

Abstract: The present study investigated the influence of attention on the human sensitivity to valence differences in emotionally negative stimuli. Event-related potentials were recorded for unattended highly negative (EN), moderately negative (MN) and neutral pictures in Experiment 1 which engaged subjects in an auditory discrimination task; and for EN, MN and neutral pictures in Experiment 2 that required visual classification of pictures. Results of both experiments displayed increased negative deflections during EN than during MN and neutral conditions at 150–250, 250–350, and 350–450ms intervals post-stimulus. Moreover, MN stimuli elicited larger negativity than did neutral stimuli during 250–350ms interval in either experiment. This developed our understanding of the human sensitivity to valence differences in negative stimuli, by revealing that the brain sensitivity to the valence strength of negative stimuli exists stably, unaffected by attention access to some extent. [Copyright &y& Elsevier]

Abstract: The present study investigated the electrophysiological correlates of the psychological processing of the collective self-relevant stimulus using a three-stimulus oddball paradigm. The results showed that P300 amplitude elicited by the collective self-relevant stimulus was larger than those elicited by familiar and unfamiliar stimuli. In addition, N250 and P300 amplitudes elicited by subjects’ own names were larger than those elicited by other name stimuli. In terms of lateralization of P300, the collective self-relevant effect was largest in the left region sites and the individual self-relevant effect was largest in the right region sites. Therefore, the present study extended previous findings by showing that the collective self, similar to the famous individual self, was psychologically important to humans. [Copyright &y& Elsevier]

Abstract: The present study investigated the effect of music-elicited moods on the subsequent affective processing through a music-primed valence categorization task. Event-related potentials were recorded for positive and negative emotional pictures that were primed by happy or sad music excerpts. The reaction time data revealed longer reaction times (RTs) for pictures following negative versus positive music pieces, irrespective of the valence of the picture. Additionally, positive pictures elicited faster response latencies than negative pictures, irrespective of the valence of the musical prime. Moreover, the main effect of picture valence, and the music by picture valence interaction effect were both significant for P2 amplitudes and for the averaged amplitudes at 500–700ms interval. Negative pictures elicited smaller P2 amplitudes than positive pictures, and the amplitude differences between negative and positive pictures were larger with negative musical primes than with positive musical primes. Similarly, compared to positive pictures, negative pictures elicited more negative deflections during the 500–700ms interval across prime types. The amplitude differences between negative and positive pictures were again larger under negative versus positive music primes at this interval. Therefore, the present study observed a clear emotional negativity bias during either prime condition, and extended the previous findings by showing increased strength of the negative bias under negative mood primes. This suggests that the neural sensitivity of the brain to negative stimuli varies with individuals’ mood states, and this bias is particularly intensified by negative mood states. [Copyright &y& Elsevier]

Abstract: The present study investigated whether the human brain is sensitive to valence differences in emotionally negative stimuli by recording event-related potentials (ERPs) for extremely negative (EN), moderately negative (MN), and neutral pictures while subjects perform a standard/deviant categorization task, irrespective of the emotional valence of the deviants. Using the same design, we also investigated the sensitivity of the human brain to valence differences in emotionally positive stimuli. Experiment 1 showed that EN stimuli elicited more negative deflections than MN stimuli in the early P2 and N2, later P3, and slow negative wave (SNW) components. In contrast, there were no differences in amplitude or latency in these components during the extremely positive (EP) and moderately positive (MP) conditions of Experiment 2. This suggests that humans are only sensitive to valence differences in negative stimuli, and that these negative valences could be processed differentially throughout the information processing stream even when individuals are highly engaged in a non-emotional task. [Copyright &y& Elsevier]

Stimuli that have been frequently used to induce self-relevant processing are highly familiar to individuals (e.g., self-name [SN] and self-face). One’s surname is an important form of collective self-concept; it represents the line of ancestry, and is psychologically salient. According to this concept, a stranger with the same surname may also elicit salient self-relevant processing, despite unfamiliarity; however, this has not yet been directly investigated. The present study adopted a three-stimulus oddball paradigm and multimodal electroencephalography to study the potential self-relevant processing of such stimuli. Behavioral results indicated that same-surname unfamiliar (SSU) names were rated more self-relevant than different-surname unfamiliar (DSU) names, although they were rated equally unfamiliar to subjects. Analysis of EEG data showed similar P2 enhancement in response to SN and SSU when compared to DSU. In contrast, the self-relevant effect on P3 amplitudes and theta synchronization decreased linearly from SN, SSU, to DSU conditions. Thus, both the behavioral and electrophysiological data indicate that unfamiliar names with the same surname can evoke reliable self-relevant processing. [ABSTRACT FROM AUTHOR]