Abstract
This review provides a description of age-related changes in hearing and cognition,
the relationship between hearing and cognition, and several potential mechanisms that
underlie the relationship. Several studies have shown a significant relationship between
peripheral hearing loss and cognitive impairment/decline but other studies have not.
Furthermore, poor performance on measures of central auditory processing has been
significantly associated with cognitive impairment. Important to understanding these
relationships are the nature of the underlying mechanisms. Possible mechanisms are
overdiagnosis, widespread neural degeneration, sensory degradation/deprivation, cognitive
resource allocation/depletion, and social isolation/depression. Overdiagnosis occurs
when hearing loss impacts tests of cognitive function or vice versa. Widespread neural
degeneration can impact hearing, cognition, or both. Sensory degradation/deprivation
due to hearing loss can result in neural degradation and reduced cognitive function.
Increased demands due to hearing loss can result in changes in neural resource allocation,
reducing available resources for cognitive function. Finally, hearing difficulties
can cause social isolation and even depression, increasing the risk for cognitive
decline. Data from our laboratory provide support for cognitive resource allocation/depletion.
Understanding all five of these mechanisms will advance the development of effective
interventions and treatments, thereby enhancing the quality of life of older adults.
Keywords
Hearing loss - peripheral hearing - central auditory processing - cognition - older
adults