Hit and False-Positive Rates for the Middle Latency Response in Patients with Central Nervous System Involvement

Abstract

We sought to determine the test efficiency of the middle latency evoked response for identifying or differentiating subjects with and without central nervous system (CNS) involvement. Receiver operating characteristic curves were established for hit and false-positive rates for 26 subjects with CNS lesions and 26 control subjects matched for age and hearing sensitivity. The lesions involved but were not limited to the auditory regions of the CNS. Middle latency evoked response latency and amplitude measurements were made for the Na and Pa waves recorded at C3 and C4 electrode sites following stimulation of the left and right ears. Intrasubject comparisons were made for ipsilateral and contralateral stimulation/recording conditions. Amplitude measures were superior to latency measures. For amplitude, percentage differences from contralateral comparisons proved to be the most sensitive and specific measure. The clinical implications of findings are discussed. Abbreviations: ABR = auditory brainstem response, CANS = central auditory nervous systems, CNS = central nervous system, MLR = middle latency response, ROC = receiver operating characteristics

Auditory Middle Latency Response in Children with and Without Dichotic Deficits

“…Reductions in response amplitude over one hemisphere, regardless of the stimulated ear, are referred to as the "electrode effect" and have been observed in patients with cortical lesions [26,33], especially those involving the temporal lobe. Conversely, lesions located subcortically [34,35], in the thalamus or upper brainstem, often manifest as an "ear effect", characterized by a reduced response following stimulation of the contralateral ear only [33,36].…”

Auditory Middle Latency Response in Children with and Without Dichotic Deficits

“…Reductions in response amplitude over one hemisphere, regardless of the stimulated ear, are referred to as the "electrode effect" and have been observed in patients with cortical lesions [26,33], especially those involving the temporal lobe. Conversely, lesions located subcortically [34,35], in the thalamus or upper brainstem, often manifest as an "ear effect", characterized by a reduced response following stimulation of the contralateral ear only [33,36].…”

Auditory Middle Latency Response in Children with and Without Dichotic Deficits

“…Reductions in response amplitude over one hemisphere, regardless of the stimulated ear, are referred to as the "electrode effect" and have been observed in patients with cortical lesions [26,33], especially those involving the temporal lobe. Conversely, lesions located subcortically [34,35], in the thalamus or upper brainstem, often manifest as an "ear effect", characterized by a reduced response following stimulation of the contralateral ear only [33,36].…”

Auditory Middle Latency Response in Children with and Without Dichotic Deficits

“…Reductions in response amplitude over one hemisphere, regardless of the stimulated ear, are referred to as the "electrode effect" and have been observed in patients with cortical lesions [26,33], especially those involving the temporal lobe. Conversely, lesions located subcortically [34,35], in the thalamus or upper brainstem, often manifest as an "ear effect", characterized by a reduced response following stimulation of the contralateral ear only [33,36].…”