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M S Zalkind

Publications and source records attributed to M S Zalkind.

15 recordsLinked to original sources
PubMed1986

Electrocochleography recorded non-invasively from the external ear.

A method is described to record cochlear evoked potentials in humans (ECochG) with a low impedance electrode on the external ear near the opening of the external auditory canal. A piezoelectric click stimulus was delivered to the ear through a polyethylene tube creating diminution of stimulus artifact and a signal delay. Wave forms resembling the cochlear microphonic (CM), summating potential (SP) and the eighth nerve action potential (N1) were differentially accentuated by changes in stimulation and recording parameters. The addition or subtraction of condensation and rarefaction click wave forms further clarified the N1 and SP, or the CM potential, respectively. These responses can be recorded with most contemporary evoked response equipment. This non-invasive method of ECochG lends itself well to the study of hearing loss and possibly other neurologic disorders, and may complement BAER examination especially when wave I is poorly delineated.

Audiometry, Evoked Response↗
PubMed1975

[The relationship between strength and the amplitude of evoked response components in the human somatosensory cortex].

The intensity curves were determined for the individual components of the human somatosensory evoked response, led off from the contra and ipsilateral motor and contralateral visual areas. The amplitude of the early components steeply increased, reached "saturation" and decreased with more intensive stimuli, their peak latencies being constant. The late components were characterised by continuous increase of amplitude, and the decrease of peak latencies for the lowest part of the curve. The responses in both frontal regions were identical, while those from the frontal and posterior leads were significantly different. The obtained data indicate a marked difference between mechanisms producing individual components of the evoked response.

Electric Stimulation↗
PubMed1975

[The relationship between achievement of a simple movement and changes in the individual components of an evoked potential].

Various moments of preparation and performance of a simple voluntary movement were tested in man with the aid of somatosensory, auditory, and visual evoked responses. An obvious attenuation of somatosensory responses closely related to the movement but independent of the spontaneous EEG changes and unaffected by the ischaemic deafferentation of the active limb, was observed. The time course of the amplitude changes was different for separate components of the same evoked response. The evoked response to stimulation of the inactive limb and the auditory evoked response changed also, while the visual evoked response remained unchanged. The described changes cannot be explained by changes in the transmission via the specific pathways. The changes in the response early components are supposed to manifest facilitation or activation of the sensory-motor cortical neurons, and those of the late, generalized complex--a decrease in the ascending message from unspecific structures.

Auditory Perception↗