Biomaterial Database

Effects of randomizing phase on the discrimination between amplitude-modulated and quasi-frequency-modulated tones. 2012

Hisaaki Tabuchi, and Ewa Borucki, and Bruce G Berg

Department of Cognitive Sciences, University of California, 2201 Social & Behavioral Sciences, Gateway Building, Irvine, CA 92697-5100, USA.

This study investigated the bandwidth of phase sensitivity. Subjects discriminated amplitude-modulated tones (AM), and quasi-frequency-modulated tones (QFM) in a two-interval, forced-choice task. An adaptive threshold procedure was used to estimate the modulation depth needed to discriminate the stimuli as a function of carrier and modulation frequency. Non-monotonicities in threshold-bandwidth functions were often observed at higher modulation frequencies. The results are discussed in terms of two potential cues: (1) waveform envelope, (2) cubic distortion products. In order to degrade the information obtained from auditory distortions, the phase for the carrier frequency was randomly sampled from a uniform distribution, which diminished the non-monotonicities with minimal effect at lower modulation frequencies. Model simulations demonstrated that phase randomization degrades distortion product cues with only a modest effect on temporal cues. Final results show that maximum bandwidths for phase sensitivity (BW(max)) were not proportional to carrier frequencies.

UI	MeSH Term	Description	Entries
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D010897	Pitch Discrimination	The ability to differentiate sound frequency or pitch.	Discrimination, Pitch,Pitch Discriminations
D011571	Psychoacoustics	The science pertaining to the interrelationship of psychologic phenomena and the individual's response to the physical properties of sound.	Psychoacoustic
D011897	Random Allocation	A process involving chance used in therapeutic trials or other research endeavor for allocating experimental subjects, human or animal, between treatment and control groups, or among treatment groups. It may also apply to experiments on inanimate objects.	Randomization,Allocation, Random
D003463	Cues	Signals for an action; that specific portion of a perceptual field or pattern of stimuli to which a subject has learned to respond.	Cue
D004192	Discrimination, Psychological	Differential response to different stimuli.	Discrimination, Psychology,Psychological Discrimination
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000161	Acoustic Stimulation	Use of sound to elicit a response in the nervous system.	Auditory Stimulation,Stimulation, Acoustic,Stimulation, Auditory
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults
D001299	Audiometry	The testing of the acuity of the sense of hearing to determine the thresholds of the lowest intensity levels at which an individual can hear a set of tones. The frequencies between 125 and 8000 Hz are used to test air conduction thresholds and the frequencies between 250 and 4000 Hz are used to test bone conduction thresholds.	Audiometries