OBJECTIVE: To examine the relative contributions of auditory functioning and cognition status to speech recognition in quiet and in noise.
METHODS: We measured speech recognition in quiet and in composite noise using the Malay Hearing in noise test on 72 native Malay speakers (60-82 years) older adults with normal to mild hearing loss. Auditory function included pure tone audiogram, gaps-in-noise, and dichotic digit tests. Cognitive function was assessed using the Malay Montreal cognitive assessment.
RESULTS: Linear regression analyses using backward elimination technique revealed that had the better ear four frequency average (0.5-4kHz) (4FA), high frequency average and Malay Montreal cognitive assessment attributed to speech perception in quiet (total r2=0.499). On the other hand, high frequency average, Malay Montreal cognitive assessment and dichotic digit tests contributed significantly to speech recognition in noise (total r2=0.307). Whereas the better ear high frequency average primarily measured the speech recognition in quiet, the speech recognition in noise was mainly measured by cognitive function.
CONCLUSIONS: These findings highlight the fact that besides hearing sensitivity, cognition plays an important role in speech recognition ability among older adults, especially in noisy environments. Therefore, in addition to hearing aids, rehabilitation, which trains cognition, may have a role in improving speech recognition in noise ability of older adults.
METHODS: Isotropic multiband functional MRI (1.5 mm) with sparse sampling (effective TR = 9000 ms, acquisition duration = 1962 ms) and continuous sampling (TR = 2000 ms) with ANC were compared in 15 normally hearing participants. A sustained broadband noise stimulus was presented to drive activation of both sustained and transient auditory responses within subcortical and cortical auditory regions.
RESULTS: Robust broadband noise-related activity was detected throughout the auditory pathways. Continuous sampling with ANC was found to give a statistically significant advantage over sparse sampling for the detection of the transient (onset) stimulus responses, particularly in the auditory cortex (P < .001) and inferior colliculus (P < .001), whereas gains provided by sparse over continuous ANC for detecting offset and sustained responses were marginal (p ~ 0.05 in superior olivary complex, inferior colliculus, medial geniculate body, and auditory cortex).
CONCLUSIONS: Sparse and continuous ANC multiband functional MRI protocols provide differing advantages for observing the transient (onset and offset) and sustained stimulus responses.
METHOD: We simulate the CT head examination using a water phantom with a standard protocol (120 kVp/180 mAs) and a low dose protocol (100 kVp/142 mAs). The table height was adjusted to simulate miscentering by 5 cm from the isocenter, where the height was miscentered superiorly (MCS) at 109, 114, 119, and 124 cm, and miscentered inferiorly (MCI) at 99, 94, 89, and 84 cm. Seven circular regions of interest were used, with one drawn at the center, four at the peripheral area of the phantom, and two at the background area of the image.
RESULTS: For the standard protocol, the mean CNR decreased uniformly as table height increased and significantly differed (p