Search PubMed⌕ Search
Home/Archive/PubMed

PubMed · 3411027

Frequency importance functions for a feature recognition test material.

V Duggirala·G A Studebaker·C V Pavlovic·R L Sherbecoe
View original source ↗Export metadata ↓

Abstract

The relative importance of different parts of the auditory spectrum to recognition of the Diagnostic Rhyme Test (DRT) and its six speech feature subtests was determined. Three normal hearing subjects were tested twice in each of 70 experimental conditions. The analytical procedures of French and Steinberg [J. Acoust. Soc. Am. 19, 90-119 (1947)] were applied to the data to derive frequency importance functions for each of the DRT subtests and the test as a whole over the frequency range 178-8912 Hz. For the DRT as a whole, the low frequencies were found to be more important than is the case for nonsense syllables. Importance functions for the feature subtests also differed from those for nonsense syllables and from each other as well. These results suggest that test materials loaded with different proportions of particular phonemes have different frequency importance functions. Comparison of the results with those from other studies suggests that importance functions depend to a degree on the available response options as well.

Explore related subjects

Acoustic StimulationAdultAudiometry, SpeechHearing DisordersHumansModels, NeurologicalSpeech Articulation TestsSpeech Discrimination TestsSpeech PerceptionJournal ArticleResearch Support, U.S. Gov't, P.H.S.

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

V Duggirala, G A Studebaker, C V Pavlovic, R L Sherbecoe. 1988. Frequency importance functions for a feature recognition test material.. https://doi.org/10.1121/1.396316

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2008

Sensory filtering phenomenology in PTSD.

Disrupted sensory filtering, or problems with suppressing irrelevant environmental sensory stimuli, has been reported in individuals with posttraumatic stress disorder (PTSD). However, the relationship of sensory filtering deficits to specific PTSD symptoms versus an association with general trauma exposure is unclear. These relationships were examined by administering self-report measures of trauma exposure, PTSD, and sensory gating phenomenology to undergraduate participants with PTSD (n=32), with trauma history but without PTSD (n=144), and with minimal trauma history (n=153). Subjects with PTSD reported greater filtering disruption than individuals in the trauma only and low trauma groups, who did not differ. Individuals endorsing reexperiencing and numbing symptoms, and females endorsing hypervigilance, reported disrupted sensory filtering phenomenology. These results suggest that impaired filtering differentiates between individuals with PTSD symptoms and asymptomatic individuals exposed to multiple traumas and low-trauma controls.

Acoustic Stimulation↗
PubMed2007

Hypoglycemia reduces the blood-oxygenation level dependent signal in primary auditory and visual cortex: a functional magnetic resonance imaging study.

Studies of the effects of hypoglycemia on the brain using neurocognitive testing have suggested that mainly complex functions subserved by secondary and tertiary cortex are affected by mild to moderate hypoglycemia and that intensively treated patients with Type I diabetes mellitus (T1DM) may have altered sensitivity to the central nervous system effects of hypoglycemia. Functional magnetic resonance imaging provides a sensitive, regionally-specific probe of possible neurophysiologic changes related to hypoglycemia in the brain. Eleven intensively-treated T1DM patients and 11 matched non-diabetic controls took part in a 2-day protocol in which functional magnetic resonance imaging (MRI) was used to measure changes in the patterns of brain activation produced by simple auditory and visual stimuli in different conditions. On one day, participants were euglycemic the entire time. On the other day, an initial 50-min euglycemic period was followed by a 50-min hypoglycemic period. Results indicated that hypoglycemia reduced the amplitude of the blood-oxygenation level dependent response in primary auditory and visual cortex to simple auditory and visual stimuli. The latency and duration of the transient hemodynamic response function were not affected. Responses to hypoglycemia were similar in diabetic and non-diabetic participants. These results suggest that mild to moderate hypoglycemia may alter the balance of blood flow and oxygen extraction when glucose levels are lowered. Intensively-treated T1DM, with its attendant frequent hypoglycemic episodes, did not seem to alter hypoglycemic responses in primary visual and auditory cortex.

Acoustic Stimulation↗
PubMed2007

Song discrimination learning in zebra finches induces highly divergent responses to novel songs.

Perceptual biases can shape the evolution of signal form. Understanding the origin and direction of such biases is therefore crucial for understanding signal evolution. Many animals learn about species-specific signals. Discrimination learning using simple stimuli varying in one dimension (e.g. amplitude, wavelength) can result in perceptual biases with preferences for specific novel stimuli, depending on the stimulus dimensions. We examine how this translates to discrimination learning involving complex communication signals; birdsongs. Zebra finches (Taeniopygia guttata) were trained to discriminate between two artificial songs, using a Go/No-Go procedure. The training songs in experiment 1 differed in the number of repeats of a particular element. The songs in experiment 2 differed in the position of an odd element in a series of repeated elements. We examined generalization patterns by presenting novel songs with more or fewer repeated elements (experiment 1), or with the odd element earlier or later in the repeated element sequence (experiment 2). Control birds were trained with only one song. The generalization curves obtained from (i) control birds, (ii) experimental birds in experiment 1, and (iii) experimental birds in experiment 2 showed large and systematic differences from each other. Birds in experiment 1, but not 2, responded more strongly to specific novel songs than to training songs, showing 'peak shift'. The outcome indicates that learning about communication signals may give rise to perceptual biases that may drive signal evolution.

Acoustic Stimulation↗