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Auditory Event-related Potentials (auditory + event-related_potential)
Selected AbstractsIs the failure to detect stimulus deviance during sleep due to a rapid fading of sensory memory or a degradation of stimulus encoding?JOURNAL OF SLEEP RESEARCH, Issue 2 2005MERAV SABRI Summary The mismatch negativity (MMN) is thought to reflect the outcome of a system responsible for the detection of change in an otherwise repetitive, homogenous acoustic environment. This process depends on the storage and maintenance of a sensory representation of the frequently presented stimulus to which the deviant stimulus is compared. Few studies have been able to record the MMN in non-rapid eye movement (NREM) sleep. This pattern of results might be explained by either a rapid fading of sensory memory or an inhibition of stimulus input prior to entry into the cortical MMN generator site. The present study used a very rapid rate of presentation in an attempt to capture mismatch-related negativity prior to the fading of sensory memory. Auditory event-related potentials were recorded from 12 subjects during a single sleep period. A 1000 Hz standard stimulus was presented every 150 ms. At random, on 6.6% of the trials, the standard was changed to either a large 2000 Hz or a small 1100 Hz deviant. In wakefulness, the large deviant elicited an extended negativity that was reduced in amplitude following the presentation of the small deviant. This negativity was also apparent during REM sleep following the presentation of the large deviant. These deviant-related negativities (DRNs) were probably a composite of N1 and MMN activity. During NREM sleep (stage 2 and slow-wave sleep), only the large deviant continued to elicit a DRN. However this DRN might be overlapped by the initial activity of a component that is unique to sleep, the N350. There was little evidence of the DRN or the MMN during sleep following the presentation of the small deviant. A rapid rate of presentation, therefore, does not preserve the MMN following small deviance within sleep. It is possible that inhibition of sensory input occurs before entry into the MMN generating system in the temporal cortex. [source] No effects of mobile phone use on cortical auditory change-detection in children: An ERP studyBIOELECTROMAGNETICS, Issue 3 2010Myoung Soo Kwon Abstract We investigated the effect of mobile phone use on the auditory sensory memory in children. Auditory event-related potentials (ERPs), P1, N2, mismatch negativity (MMN), and P3a, were recorded from 17 children, aged 11,12 years, in the recently developed multi-feature paradigm. This paradigm allows one to determine the neural change-detection profile consisting of several different types of acoustic changes. During the recording, an ordinary GSM (Global System for Mobile Communications) mobile phone emitting 902,MHz (pulsed at 217,Hz) electromagnetic field (EMF) was placed on the ear, over the left or right temporal area (SAR1g,=,1.14,W/kg, SAR10g,=,0.82,W/kg, peak value,=,1.21,W/kg). The EMF was either on or off in a single-blind manner. We found that a short exposure (two 6,min blocks for each side) to mobile phone EMF has no statistically significant effects on the neural change-detection profile measured with the MMN. Furthermore, the multi-feature paradigm was shown to be well suited for studies of perception accuracy and sensory memory in children. However, it should be noted that the present study only had sufficient statistical power to detect a large effect size. Bioelectromagnetics 31:191,199, 2010. © 2009 Wiley-Liss, Inc. [source] Brain responses to surprising sounds are related to temperament and parent,child dyadic synchrony in young childrenDEVELOPMENTAL PSYCHOBIOLOGY, Issue 6 2010Anu-Katriina Pesonen Abstract This study investigated the relationship between temperament characteristics, parent,child dyadic synchrony and auditory event-related potentials (ERP) in 15 two-year-old children. Temperament was assessed with the Early Childhood Behavior Questionnaire, and parent,child dyadic synchrony was analyzed from video-taped play situations. Involuntary switching of attention toward surprising sounds was measured with auditory ERPs by quantifying the P3a response for repeated and nonrepeated novel, naturally varying sounds, presented in a continuous repetitive sound sequence. Lower negative emotionality, higher effortful control and higher dyadic synchrony were associated with larger P3a responses to repeated novel sounds. The results demonstrate that temperament is related to P3a responses in early childhood, and that parent,child synchrony associates with both temperament and P3a responses in a theoretically meaningful way. © 2010 Wiley Periodicals, Inc. Dev Psychobiol 52: 513,523, 2010. [source] The processing of sound duration after left hemisphere stroke: Event-related potential and behavioral evidencePSYCHOPHYSIOLOGY, Issue 4 2001T.-M. Ilvonen The ability of left-hemisphere stroke patients (n= 8) and healthy control subjects (n= 8) to process sounds preattentively and attentively was studied by recording auditory event-related potentials (ERPs) and behavioral responses. For the right-ear stimulation, the mismatch negativity (MMN) was significantly smaller in the patients than control subjects over both hemispheres. For the left-ear stimuli, the MMN was significantly smaller in the patient group than in the control group over the left hemisphere, whereas no group differences were obtained over the right hemisphere. In addition, the N1 amplitude was reduced bilaterally for the right-ear stimulation (with the reduction being larger over the left hemisphere), whereas no significant effects on the N1 amplitude were found for the left-ear stimulation. Behaviorally, the patients detected significantly fewer deviant tones than did the control subjects irrespective of the stimulated ear. The present results thus suggest that the long-latency ERPs can be used to probe such auditory processing deficits that are difficult to define with behavioral measures. Especially by recording MMN to monaural stimuli, the discrimination accuracy can be separately determined for the left and right temporal lobes. [source] Auditory P300 Event-Related Potentials and Neurocognitive Functions in Opioid Dependent Men and Their BrothersTHE AMERICAN JOURNAL ON ADDICTIONS, Issue 3 2009Shubh Mohan Singh MD Event-related-potentials (especially P300) and cognitive functioning as potential endophenotypes have not been studied in opioid dependence. We compared auditory P300 and cognitive functions in opioid-dependent men, their brothers and normal controls in an exploratory study with a view to find shared genetic factors in the development of opioid dependence. Twenty abstinent opioid-dependent males, their brothers and twenty matched controls were administered Wisconsin card sorting test (WCST), digit span test, trail making test-B, and auditory event-related potentials (P300) from an oddball task were recorded. The opioid dependent group performed the worst, the brothers group was intermediate, and the control group performed the best on tests of WCST, digit span and trail making test-B. The opioid dependent group had the smallest amplitudes and longest latencies of P300, and was followed by the brothers group who had an intermediate position and the control group who had the largest amplitudes and the shortest latencies. P300 and executive neurocognitive functions can be considered endophenotypes for the genetic study of vulnerability to opioid dependence. These are reflective of executive dysfunction and disrupted behavioral inhibition and the intermediate position of brothers suggests a common genetic substrate as a component of the etiology. [source] | ||||||||||