David L. McPherson

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Binaural interaction in the brainstem and middle latency auditory evoked potentials to intensity (dI) and timing differences (dT) between the two ears was studied in 10 normal hearing young adults. A component reflecting binaural interaction in the brainstem potentials occurred at approximately 7 ms and was of largest amplitude when dI and dT were 0. The(More)
An 11-yr-old girl had an absence of sensory components of auditory evoked potentials (brainstem, middle and long-latency) to click and tone burst stimuli that she could clearly hear. Psychoacoustic tests revealed a marked impairment of those auditory perceptions dependent on temporal cues, that is, lateralization of binaural clicks, change of binaural(More)
Fifteen infants with hydrocephalus ranging in age from 32 to 43 weeks from conception were studied. The auditory brainstem response (ABR) was measured 48 h prior to the placement of a CSF shunt and within 5 days following shunt insertion. Results of this study showed a general improvement in the ABR following placement of the shunt. No consistent patterns(More)
Binaural interactions in brain-stem auditory evoked potentials and in middle latency auditory evoked potentials were studied in 18 normal hearing adults and 10 normal term infants. Binaural interactions at the times of ABR waves V and VI were comparable in term infants and adults. Binaural interaction during the time domain of the middle latency auditory(More)
Auditory middle latency response (AMLR) brain maps were obtained in 11 young adults with normal hearing. AMLR waveforms were elicited with monaural clicks presented at three stimulus intensity levels (50, 70, and 90 dB nHL). Recordings were made for right and left ear stimulus presentations. All recordings were obtained in an eyes open/awake status for each(More)
Despite the large number of individuals who speak Russian, only a limited number of high-quality speech audiometry materials are available in a standard dialect of Russian. Thus, the purpose of this study was to develop and evaluate speech audiometry materials that can be used to measure word recognition and SRT testing in quiet for native speakers of(More)
This investigation confirmed previous studies indicating that the middle and inner ear of the guinea pig have a pronounced tendency to healing. Middle ear hemorrhage of surgical origin appears to stop quickly in the guinea pig. A surgically created perforation of the round window with or without removal of perilymphatic fluid by suction resulted in a(More)
The contribution of the cerebral cortex to the generation of sensory evoked potentials was studied in an infant with hydranencephaly. On CT scan no tissue above the thalamus was noted. Long-latency potentials to auditory stimuli were absent whereas the short-latency or brain-stem auditory evoked potentials and some of the components of the middle latency(More)
The electrophysiological findings show a time and pressure related decrease in function of the CM and the N1 potentials. Sudden changes were correlated with tympanic membrane perforations. Some of the decreased function is accounted for by middle ear effusion and hemorrhages, reducing mechanically the transmission of sound energy through the middle ear.(More)