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Perceptual Processing (perceptual + processing)
Selected AbstractsEnhanced perceptual processing of speech in autismDEVELOPMENTAL SCIENCE, Issue 1 2008Anna Järvinen-Pasley Theories of autism have proposed that a bias towards low-level perceptual information, or a featural/surface-biased information-processing style, may compromise higher-level language processing in such individuals. Two experiments, utilizing linguistic stimuli with competing low-level/perceptual and high-level/semantic information, tested processing biases in children with autism and matched controls. Whereas children with autism exhibited superior perceptual processing of speech relative to controls, and showed no evidence of either a perceptual or semantic processing bias, controls showed a tendency to process speech semantically. The data provide partial support to the perceptual theories of autism. It is additionally proposed that the pattern of results may reflect different patterns of attentional focusing towards single or multiple stimulus cues in speech between children with autism and controls. [source] Co-induction of activity-dependent genes in songbirdsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2005Tarciso A. F. Velho Abstract Song behavior in songbirds induces the expression of activity-dependent genes in brain areas involved in perceptual processing, production and learning of song. This genomic response is thought to represent a link between neuronal activation and long-term changes in song-processing circuits of the songbird brain. Here we demonstrate that Arc, an activity-regulated gene whose product has dendritic localization and is associated with synaptic plasticity, is rapidly induced by song in the brain of zebra finches. We show that, in the context of song auditory stimulation, Arc expression is induced in several telencephalic auditory areas, most prominently the caudomedial nidopallium and mesopallium, whereas in the context of singing, Arc is also induced in song control areas, namely nucleus HVC, used as a proper name, the robust nucleus of the arcopallium and the interface nucleus of the nidopallium. We also show that song-induced Arc expression co-localizes at the cellular level with those of the transcriptional regulators zenk and c-fos, and that the song induction of these three genes is dependent on activation of the mitogen-activated protein kinase signaling pathway. These findings provide evidence for an involvement of Arc in the brain's response to birdsong. They also demonstrate that genes representing distinct genomic and cellular regulatory programs, namely early effectors and transcription factors, are co-activated in the same neuronal cells by a naturally learned stimulus. [source] Attentional load modifies early activity in human primary visual cortexHUMAN BRAIN MAPPING, Issue 5 2009Karsten S. Rauss Abstract Recent theories of selective attention assume that the more attention is required by a task, the earlier are irrelevant stimuli filtered during perceptual processing. Previous functional MRI studies have demonstrated that primary visual cortex (V1) activation by peripheral distractors is reduced by higher task difficulty at fixation, but it remains unknown whether such changes affect initial processing in V1 or subsequent feedback. Here we manipulated attentional load at fixation while recording peripheral visual responses with high-density EEG in 28 healthy volunteers, which allowed us to track the exact time course of attention-related effects on V1. Our results show a modulation of the earliest component of the visual evoked potential (C1) as a function of attentional load. Additional topographic and source localization analyses corroborated this finding, with significant load-related differences observed throughout the first 100 ms post-stimulus. However, this effect was observed only when stimuli were presented in the upper visual field (VF), but not for symmetrical positions in the lower VF. Our findings demonstrate early filtering of irrelevant information under increased attentional demands, thus supporting models that assume a flexible mechanism of attentional selection, but reveal important functional asymmetries across the VF. Hum Brain Mapp 2009. © 2008 Wiley-Liss, Inc. [source] The selective processing of briefly presented affective pictures: An ERP analysisPSYCHOPHYSIOLOGY, Issue 3 2004Harald T. Schupp Abstract Recent event-related potential (ERP) studies revealed the selective processing of affective pictures. The present study explored whether the same phenomenon can be observed when pictures are presented only briefly. Toward this end, pleasant, neutral, and unpleasant pictures from the International Affective Pictures Series were presented for 120 ms while event related potentials were measured by dense sensor arrays. As observed for longer picture presentations, brief affective pictures were selectively processed. Specifically, pleasant and unpleasant pictures were associated with an early endogenous negative shift over temporo-occipital sensors compared to neutral images. In addition, affective pictures elicited enlarged late positive potentials over centro-parietal sensor sites relative to neutral images. These data suggest that a quick glimpse of emotionally relevant stimuli appears sufficient to tune the brain for selective perceptual processing. [source] Mazes and music: using perceptual processing to release verbal overshadowingAPPLIED COGNITIVE PSYCHOLOGY, Issue 8 2002Kimberly Finger Verbal overshadowing occurs when participants describe a previously viewed non-verbal stimulus such as a face prior to a recognition memory test. The results of numerous studies indicate that recognition accuracy is lower when participants describe the face or other non-verbal stimulus as compared to a no-description control condition. In the present two-experiment study, verbal overshadowing was alleviated when participants engaged in a non-verbal task that emphasized perceptual processing subsequent to describing the face but prior to the recognition memory test. In Experiments 1 and 2, participants viewed a face and then either described the face or completed a distractor task. Next, participants in Experiment 1 engaged in a perceptual task in the form of a series of mazes or a verbal task. Participants who described the face and completed the mazes experienced a release from verbal overshadowing as compared to participants who described the face and completed the verbal task. In Experiment 2, verbal overshadowing was alleviated when participants listened to instrumental music after describing the face, thus demonstrating that an auditory perceptual task can also release verbal overshadowing. The results of these two experiments provide support for a processing shift interpretation of verbal overshadowing. Furthermore, the results indicate this shift can be alleviated, and perceptual processing reinstated, by engaging in an unrelated perceptually oriented task such as completing a maze or listening to music. Copyright © 2002 John Wiley & Sons, Ltd. [source] Transfer appropriate processing for prospective memory testsAPPLIED COGNITIVE PSYCHOLOGY, Issue 7 2000Beat Meier Transfer appropriate processing (TAP) is the assumption that retrospective memory test performance reflects the overlap between study and test phase processing. In a task analysis, we identify a similar sequential-type of processing overlap in prospective memory (ProM) situations. In addition, ProM test performance can also involve a concurrent overlap between processes engaged for an ongoing task and those required for recognizing relevant cues. A review of the ProM literature shows consistent TAP effects due to sequential processing overlap manipulations, but inconclusive findings for concurrent processing overlap manipulations. We examined the latter in a new experiment with young adult participants. The ongoing task required either semantic or perceptual processing of words, and the ProM task required either semantic or perceptual processing of words. Consistent with TAP, performance was higher when the ongoing task and the ProM task required the same kind of processing (i.e. semantic,semantic, perceptual,perceptual) rather than different kinds of processing (i.e. semantic,perceptual, perceptual,semantic). Copyright © 2000 John Wiley & Sons, Ltd. [source] Involuntary interpretation of social cues is compromised in autism spectrum disordersAUTISM RESEARCH, Issue 4 2009Tjeerd Jellema Abstract A new social distance judgment task was used to measure quantitatively the extent to which social cues are immediately and involuntary interpreted by typically developing (TD) individuals and by individuals with autism spectrum disorders (ASD). The task thus tapped into the ability to involuntary "pick up" the meaning of social cues. The cues tested were social attention and implied biological motion. Task performance of the ASD and TD groups was similarly affected by a perceptual low-level illusion induced by physical characteristics of the stimuli. In contrast, a high-level illusion induced by the implications of the social cues affected only the TD individuals; the ASD individuals remained unaffected (causing them to perform superior to TD controls). The results indicate that despite intact perceptual processing, the immediate involuntary interpretation of social cues can be compromised. We propose that this type of social cue understanding is a distinct process that should be differentiated from reflective social cue understanding and is specifically compromised in ASD. We discuss evidence for an underpinning neural substrate. [source] | |||||||||||||