OBJECTIVE To evaluate the prognostic value of short-latency median nerve somatosensory evoked potentials and brainstem auditory evoked potentials in outcome prediction for comatose cardiac arrest patients treated with hypothermia. DESIGN Prospective, randomized, controlled trial of mild hypothermia after out-of-hospital cardiac arrest; a substudy of the European Hypothermia After Cardiac Arre...

OBJECTIVE This study examined morphological changes in the cortical auditory evoked potential (CAEP) waveform as a function of varying stimulation rate. Stimuli were presented in a paradigm which indirectly assesses the refractory properties of the underlying neuronal generators. METHODS CAEPs were recorded in 50 normal-hearing children (3-12 years) and 10 young adults (24-26 years). A speech...

Considerable evidence exists for developmental changes in latency and amplitude of the auditory evoked potential termed N100. However, it is widely recognized that the N100 wave comprises multiple, temporally overlapping neural generators, and few data are available addressing either individual generator development or mechanisms behind such change. Using magnetoencelphalographic (MEG) measurem...

Averaging single trial evoked potential data to produce an estimate of the underlying signal obscures trial-to-trial variation in the response. We describe a method for estimating slow changes in the evoked potential signal by smoothing the data over trials. We discuss the crucial issue of deciding how much to smooth and suggest that an appropriate smoothing parameter is one that minimizes the ...

Mismatch negativity (MMN) was measured on normal-hearing young adult women and men to determine the effect of gender on this auditory evoked potential (AEP). In the experimental condition, recordings were obtained for 1000-Hz tone bursts presented at 75 dB nHL (standard stimuli) and 60 dB nHL (deviant stimuli). AEPs also were obtained in a control condition in which all stimuli were presented a...

Many researchers have investigated the possibility of using auditory evoked potentials (AEPs) to objectively diagnose tinnitus. Published AEP studies suggest differences in neural activity in individuals with tinnitus compared to control groups, but the results are not consistent. There is a great deal of variability seen in auditory evoked- and event-related potentials in the tinnitus populati...

OBJECTIVE To investigate the contributions of energetic and informational masking to neural encoding and perception in noise, using oddball discrimination and sentence recognition tasks. DESIGN P3 auditory evoked potential, behavioral discrimination, and sentence recognition data were recorded in response to speech and tonal signals presented to nine normal-hearing adults. Stimuli were presen...

This report describes the frequency response of the oddball paradigm upon auditory stimuli. Other reports related to wavelet analysis of the same ERPs (Demiralp et al., 1999) and the application of visual signals (Schürmann et al., this volume) indicate that the P300 response has a dominant delta response oscillation, independent of the modality of the stimulation. Moreover, the adaptive digita...

INTRODUCTION Long-latency auditory evoked potentials represent the cortical activity related to attention, memory, and auditory discrimination skills. Acoustic signal processing occurs differently between verbal and nonverbal stimuli, influencing the latency and amplitude patterns. OBJECTIVE To describe the latencies of the cortical potentials P1, N1, P2, N2, and P3, as well as P3 amplitude, ...

The auditory evoked potential (AEP) is correlated to anaesthetic depth. The AEP has been used in rats, pigs, dogs and humans to assess anaesthetic depth. This study was undertaken to determine whether the AAI Index derived from the AEP correlated with changes in end tidal isoflurane concentration in dogs. The average AAI Index was 21.8 +/- 10.5 and isoflurane concentration was 1.7 +/- 0.4%. Dat...