Shrinkage in the perceived duration of speech and tone by acoustic replacement1

Abstract: To investigate mechanisms for perceiving the duration of an auditory event, an effect of perceptual grouping upon perceived duration was studied psychophysically. In the first experiment, the perceived duration of a spoken word was measured under three conditions of acoustic continuity (i.e., (a) intact, (b) noise‐replaced, and (c) gap‐replaced) as a function of the duration of the target stimulus. Under the noise‐replaced condition, a portion of the target stimulus was physically replaced with a noise burst. Under the gap‐replaced condition, the replacement was made with a gap. The gap‐replacement resulted in a prominent shrinkage of the perceived duration. In the case of noise‐replacement, the amount of shrinkage was moderate but highly significant, although the word employed was perceived to be phonetically intact. Independent of this effect of replacement, the amount of shrinkage was also affected by the physical duration of the target stimulus. The second experiment tested an effect of noise replacement on the perceived duration of a tone burst. In this case, the noise replacement also shrunk the perceived duration of the non‐speech stimulus. This noise‐induced shrinkage could be regarded as being general for the auditory duration. The phenomenon is discussed in relation to a revised model for perceived duration.     

Homogeneity perception as a reaction to identity threat: effects of status difference in a simulated society game

The present study examined how members of low status groups would react to a threat to their social identity. Undergraduates participated in a ‘simulated society game,’ and were divided into four groups, each of which was assigned either a high or low status. During a series of game sessions with intergroup competition and cooperation, participants estimated the range of distributions among in‐ group and out‐group members regarding various traits. The central tendency and variability derived from each estimate were analysed. Members of the low status groups deprecated their in‐group with respect to a status‐defining trait, but showed in‐group favouritism regarding alternative, status‐irrelevant traits. Furthermore, the low status members judged their in‐group as more homogeneous than the out‐group regarding the alternative traits, particularly when they were compared to a high status group. The results were interpreted as an indication of a subtle form of maintaining positive in‐group evaluations. Theoretical and methodological implications for the study of status effects are discussed. Copyright © 2004 John Wiley & Sons, Ltd.     

Effects of semantic context and event-related potentials: N400 correlates with inhibition effect

Two experiments investigated the modulation of event-related brain potentials (ERPs) by semantic context. A prime-target pair was visually presented in each trial of a lexical decision task. For word targets, three types of relatedness conditions were employed: (1) Related word condition (e.g., school-teacher); (2) Neutral word condition (e.g., [symbol: see text] - number); (3) Unrelated word c((e.g., hospital-potato). In Experiment 1, the reaction time for unrelated targets was longer than that for neutral targets (inhibition effect) which was longer than that for related targets (facilitation effect). The N400 amplitude in the unrelated targets was larger compared to those in the related and neutral targets, which did not differ. In Experiment 2, where only the facilitation effect was obtained, the N400 amplitude did not differ among conditions.     

Effect of unpleasant loud noise on hippocampal activities during picture encoding: an fMRI study

The functional link between the amygdala and hippocampus in humans has not been well documented. We examined the effect of unpleasant loud noise on hippocampal and amygdaloid activities during picture encoding by means of fMRI, and on the correct response in humans. The noise reduced activity in the hippocampus during picture encoding, decreased the correct response and increased the activity of the amygdala. A path diagram using structural equation modeling suggested that hippocampus activity might be depressed by high amygdala activity. Therefore, noise should diminish memory by reducing hippocampal activity, which might be depressed by high amygdala activity.     

A single bout of resistance exercise can enhance episodic memory performance

Acute aerobic exercise can be beneficial to episodic memory. This benefit may occur because exercise produces a similar physiological response as physical stressors. When administered during consolidation, acute stress, both physical and psychological, consistently enhances episodic memory, particularly memory for emotional materials. Here we investigated whether a single bout of resistance exercise performed during consolidation can produce episodic memory benefits 48 h later. We used a one-leg knee extension/flexion task for the resistance exercise. To assess the physiological response to the exercise, we measured salivary alpha amylase (a biomarker of central norepinephrine), heart rate, and blood pressure. To test emotional episodic memory, we used a remember-know recognition memory paradigm with equal numbers of positive, negative, and neutral IAPS images as stimuli. The group that performed the exercise, the active group, had higher overall recognition accuracy than the group that did not exercise, the passive group. We found a robust effect of valence across groups, with better performance on emotional items as compared to neutral items and no difference between positive and negative items. This effect changed based on the physiological response to the exercise. Within the active group, participants with a high physiological response to the exercise were impaired for neutral items as compared to participants with a low physiological response to the exercise. Our results demonstrate that a single bout of resistance exercise performed during consolidation can enhance episodic memory and that the effect of valence on memory depends on the physiological response to the exercise.     

Projecting group liking and ethnocentrism on in-group members: False consensus effect of attitude strength

The purpose of the present study was to examine the social projection effect concerning the strength of national attitudes. Japanese respondents sampled from the general population judged how patriotic and nationalistic opinions were distributed among Japanese (i.e. in-group) and American (out-group) citizens. The respondents' own positions regarding these attitude dimensions were also measured. As predicted, the respondents inflated estimates of the endorsement for positions close to their own, particularly when the target was the in-group. Estimates of opinion distributions in the out-group converged around stereotypic positions. The apparent projection effect in patriotism (i.e. in-group liking) was likely mediated by abstract trait evaluations of the home country, while the projection of nationalism (i.e. ethnocentrism) appeared to be a direct result of projection without such mediation. Different processes such as the motivation for cognitive consistency and the need to achieve social identity of the group were suggested to underlie projection effects in different domains. Implications of the results for the study of stereotyping and intergroup conflict are discussed.     

Identification with a wrongful subgroup and the feeling of collective guilt

The present study examined the relationship between group identification and the feeling of collective guilt. This study argued that identification with a subgroup of one's ingroup (subgroup identification) would predict the feeling of collective guilt better than identification with the whole ingroup (whole‐group identification). To manipulate the level of subgroup identification, we instructed participants to imagine the presence of a close friend (vs a friend of one's close friend) in a fictitious subgroup. In Experiment 1, we predicted and found that high subgroup identifiers experienced less collective guilt compared to low subgroup identifiers, regardless of their degree of whole‐group identification. In contrast, the results from Experiment 2 indicated that when the presence of the third party was made salient, high subgroup identifiers experienced more collective guilt in comparison to low subgroup identifiers. The importance of interpersonal connections for collective responsibility and the facilitating role of the third party for reconciliation of the intergroup conflicts are discussed.     

Patriotism, Nationalism, and Internationalism Among Japanese Citizens: An Etic–Emic Approach

The present study examined national attitudes among Japanese citizens. A National Identity Scale was developed and administered to a non–student sample (n = 385) and an undergraduate sample (n = 586) in a metropolitan area of Japan. The results revealed aspects that are common (i.e., etic) to different nationalities and those that are indigenous (i.e., emic) to Japanese people. Factor analyses identified etic factors of patriotism (i.e., love of the homeland), nationalism (belief in superiority over other nations), and internationalism (preference for international cooperation and unity). Attachment to the ingroup and ethnocentrism were thus shown to be separate dimensions. Distinct from these factors, commitment to national heritage emerged as an emic component of Japanese national identity. The discriminant validity of these factors was demonstrated in differential relationships with other variables, such as ideological beliefs and amount of knowledge. Commitment to national heritage was associated with conservatism, whereas internationalism was related to liberal ideology, a high level of media exposure, and knowledge of international affairs. Implications for the study of intergroup and international relations are discussed.     

Mediating effect of environmental rewards on the relation between goal-directed behaviour and anhedonia

Depression can be explained by certain behavioural patterns, especially low levels of environmental rewards; it is generally accompanied by infrequent goal-directed behaviour, increased depressed mood, and anhedonia. However, no research has statistically examined the mediating effect of environmental rewards on the relation between goal-directed behaviour and the symptoms of depressed mood or anhedonia. This study sought to determine whether such a mediating effect of environmental rewards is present in cross-sectional study. The participants included 101 patients diagnosed with major depressive disorders. Data were collected through three questionnaires measuring depression and behavioural patterns that maintain depression: the Center for Epidemiologic Studies Depression Scale (CES-D), the Environmental Reward Observation Scale (EROS), and the Behavioral Activation for Depression Scale—Short Form (BADS-SF). Mediation analysis was conducted using depressed mood and anhedonia as dependent variables, environmental rewards as the mediating variable, and goal-directed behaviour as the independent variable. Environmental rewards significantly mediated the relationship between goal-directed behaviour and anhedonia but not that between goal-directed behaviour and depressed mood. No significant relationships were found among depressed mood, goal-directed behaviour and environmental rewards. From these results, we conclude that low levels of environmental rewards accompanied by infrequent goal-directed behaviour can lead to increased anhedonia but not depressed mood.