However, an oscillatory response at higher gamma frequency and long latency responses, both hypothesized to be related to higher order auditory processing, declined across age groups.
More than 50% of pediatric cancer survivors will develop long-term complications, including cardiovascular, gonadal, and gastrointestinal/hepatic dysfunction, neurocognitive sequelae, auditory complications, and decline in growth, with approximately 25% of cases being severe [ 290].
Perhaps the dolphin's hearing had been affected by the shipping and boating noises in his habitat; but more likely, the researchers say, his auditory sensitivity had declined for the same reason it does in humans, and likely most mammals: He had lived a long life.
A decline in auditory function is almost a default feature of aging, with over two-thirds of adults 70 or older afflicted by at least some hearing loss.
Graydon et al. [21] found a decline in auditory verbal memory following left unilateral temporal lobectomy and a decline in visuospatial memory following right unilateral lobectomy.
As expected, this shows a monotonic decline with auditory SNR.
This would speak well for a possible causal relationship between auditory deprivation and cognitive decline.
Declines in auditory acuity [9] [10], temporal processing [11], memory [12], speed of information processing [13] [14] and the ability to filter out irrelevant competing auditory input [15] [16] also contribute to difficulties reported by older adults for hearing SIN.
We found that the average azimuthal tuning for the high frequency sound was actually less sharp than that for the low frequency sound (width at half-max: high = 42°±14°, low = 32°±12°; Fig. 4D,E), implying that the decline in the auditory system's capacity to encode IPD at high frequencies is more severe than the increase in the rate of change in IPD with sound azimuth.
This is in line with emerging evidence that there might be a causal relationship between sensory deprivation (as captured here with a simple auditory threshold measure) and cognitive decline.
