The Use of the Gaps-In-Noise Test as an Index of the Enhanced Left Temporal Cortical Thinning Associated with the Transition between Mild Cognitive Impairment and Alzheimer's Disease.

BACKGROUND

The known link between auditory perception and cognition is often overlooked when testing for cognition.

PURPOSE

To evaluate auditory perception in a group of older adults diagnosed with mild cognitive impairment (MCI).

RESEARCH DESIGN

A cross-sectional study of auditory perception.

STUDY SAMPLE

Adults with MCI and adults with no documented cognitive issues and matched hearing sensitivity and age.

DATA COLLECTION

Auditory perception was evaluated in both groups, assessing for hearing sensitivity, speech in babble (SinB), and temporal resolution.

RESULTS

Mann-Whitney test revealed significantly poorer scores for SinB and temporal resolution abilities of MCIs versus normal controls for both ears. The right-ear gap detection thresholds on the Gaps-In-Noise (GIN) Test clearly differentiated between the two groups (p < 0.001), with no overlap of values. The left ear results also differentiated the two groups (p < 0.01); however, there was a small degree of overlap ∼8-msec threshold values. With the exception of the left-ear inattentiveness index, which showed a similar distribution between groups, both impulsivity and inattentiveness indexes were higher for the MCIs compared to the control group.

CONCLUSIONS

The results support central auditory processing evaluation in the elderly population as a promising tool to achieve earlier diagnosis of dementia, while identifying central auditory processing deficits that can contribute to communication deficits in the MCI patient population. A measure of temporal resolution (GIN) may offer an early, albeit indirect, measure reflecting left temporal cortical thinning associated with the transition between MCI and Alzheimer's disease.