FREQUENCY OF SEEING FUNCTIONS FOR INTENSITY DISCRIMINATION AT VARIOUS LEVELS OF ADAPTING INTENSITY

1. The percentage of times a human subject detects an increment (ΔI) in intensity was determined as a function of the magnitude of the increment and the magnitude of the stimulus (I) to which the increment is added. 2. Foveal stimulation was used, and five frequency of seeing curves were obtained at each of nine values of adapting intensity covering the range from –1.45 to 4.45 log photons. Each frequency of seeing curve shows the percentage of times an increment in intensity is detected as a function of the logarithm of the increment. 3. The slope of the frequency of seeing curve increases slightly with an increase in I and finally becomes independent of I at medium to high intensities. 4. The implications of the results for quantum theories of visual excitation are considered.

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Auditory Training to Improve Speech Perception and Self-Efficacy in Aging Adults

Journal of Speech Language and Hearing Research ◽

10.1044/2019_jslhr-19-00355 ◽

2020 ◽

Vol 63 (4) ◽

pp. 1270-1281

Author(s):

Leah Fostick ◽

Riki Taitelbaum-Swead ◽

Shulamith Kreitler ◽

Shelly Zokraut ◽

Miriam Billig

Keyword(s):

Speech Perception ◽

Self Efficacy ◽

Temporal Order Judgment ◽

Auditory Training ◽

Intensity Discrimination ◽

Training Design ◽

Auditory Temporal Processing ◽

Temporal Properties ◽

Computer Based ◽

Aging Adults

Purpose Difficulty in understanding spoken speech is a common complaint among aging adults, even when hearing impairment is absent. Correlational studies point to a relationship between age, auditory temporal processing (ATP), and speech perception but cannot demonstrate causality unlike training studies. In the current study, we test (a) the causal relationship between a spatial–temporal ATP task (temporal order judgment [TOJ]) and speech perception among aging adults using a training design and (b) whether improvement in aging adult speech perception is accompanied by improved self-efficacy. Method Eighty-two participants aged 60–83 years were randomly assigned to a group receiving (a) ATP training (TOJ) over 14 days, (b) non-ATP training (intensity discrimination) over 14 days, or (c) no training. Results The data showed that TOJ training elicited improvement in all speech perception tests, which was accompanied by increased self-efficacy. Neither improvement in speech perception nor self-efficacy was evident following non-ATP training or no training. Conclusions There was no generalization of the improvement resulting from TOJ training to intensity discrimination or generalization of improvement resulting from intensity discrimination training to speech perception. These findings imply that the effect of TOJ training on speech perception is specific and such improvement is not simply the product of generally improved auditory perception. It provides support for the idea that temporal properties of speech are indeed crucial for speech perception. Clinically, the findings suggest that aging adults can be trained to improve their speech perception, specifically through computer-based auditory training, and this may improve perceived self-efficacy.

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