The effect of frequency uncertainty on the detection of tonal signals in noise was studied using a modified probe-signal method. Widths of the listening bands used during detection were measured directly, allowing for an analysis that separates the effects of having to monitor multiple independent bands from those due to ...

Comodulation masking release (CMR) is a phenomenon that demonstrates the sensitivity of the auditory system to across-frequency differences in the temporal modulation pattern of a complex waveform. In this paper, we review briefly some of the data on the physical parameters that affect CMR and describe models that have been ...

Amplitude envelopes derived from speech have been shown to facilitate speech-reading to varying degrees, depending on how the envelope signals were extracted and presented and on the amount of training given to the subjects. In this study, three parameters related to envelope extraction and presentation were examined using both easy ...

These experiments examine the effects of masker level on the magnitude of comodulation masking release (CMR). In experiment 1, threshold was measured for detecting a 2000-Hz signal in noise bands 100 or 3200 Hz wide, centered at the signal frequency. The noise was either amplitude modulated by a low-pass-filtered noise, ...

When attending to a tone at a given frequency, listeners are most sensitive to that tone and others within a restricted band of frequencies surrounding it. This region of enhanced sensitivity defines the attention band that was measured in two experiments using a modified version of the probe-signal method of ...

Simultaneous-masked psychophysical tuning curves were obtained from normal-hearing listeners using low-level (20-25 dB SPL) probe tones in quiet and high-level (60 dB SPL) probe tones, both in quiet and in the presence of a broad-band background noise. The background noise was introduced to eliminate combination tones or combination bands and ...

Simultaneous-masked psychophysical tuning curves were measured with narrow-band noise maskers varying in bandwidth from 40 Hz to 800 Hz to determine the masker bandwidths at which combination-band detection cues no longer influence tuning-curve shapes. Tuning curves were obtained at 1000 and 4000 Hz from normal-hearing listeners using high-level (60 dB ...

Two experiments were performed that examined the relation between frequency selectivity for diotic and dichotic stimuli. Subjects were eight normal-hearing listeners. In each experiment, a 500-Hz pure tone of 400-ms duration was presented in continuous noise. In the diotic listening conditions, a signal and noise were presented binaurally with no ...

Gap detection thresholds were measured by forced-choice procedure for conditions where the duration of a silent gap was varied adaptively between pairs of sinusoidal markers of the same or different frequency. Frequencies of the first sinusoid in a pair of markers ranged from F1 = 500 to 4000 Hz. Second-sinusoid ...

Temporal gap detection thresholds were obtained for two species of birds, budgerigars and zebra finches, which are known to have different auditory filter bandwidths. Both species showed gap detection thresholds of about 2.5 msec for broadband noise stimuli. Comparing octave bands of noise centered at 1, 3, and 5 kHz, ...

Recent psychophysical studies have shown that the detection of an intensity increment superimposed on the center component (1 kHz) of a multitone complex (1, 3, 7, or 11 components) improves as more components are added outside of the critical band. It has been suggested that this form of intensity discrimination ...

This paper examines some of the factors that can affect the magnitude of comodulation masking release (CMR). In experiment I, psychometric functions were measured for the detection of a 1-kHz sinusoidal signal in a "multiplied" narrow-band noise centered at 1 kHz (reference condition) and the same noise with two comodulated ...

A perceptual-components architecture for digital video partitions the image stream into signal components in a manner analogues to that used in the human visual system. These components consist of achromatic and opponent color channels, divided into static and motion channels, further divided into bands of particular spatial frequency and orientation. ...

This paper is concerned with aspects of temporal integration and across-frequency integration in signal detection. Previous experiments on the detection of brief broadband signals (clicks) in continuous broadband noise revealed efficient spectral integration. The extent to which this effect is restricted to a critical time window was investigated by manipulating ...

The threshold of a 1250-Hz tonal signal was measured in the presence of five noise bands (each 50 Hz wide, centered at 850, 1050, 1250, 1450, and 1650 Hz) under five conditions of uncertainty about the waveform type ("correlated" or "uncorrelated"), and/or the specific waveform sample to be presented. The ...

1. The organization of azimuthal sensitivity of units across the dorsoventral extent of primary auditory cortex (AI) was studied in electrode penetrations made along frequency-band strips of AI. Azimuthal sensitivity for each unit was represented by a mean azimuth function (MF) calculated from all azimuth functions obtained to characteristic frequency ...

A frequency specificity for the response of bone tissue to a physical stimulus is proposed. This is obtained by comparing the spectral power of exogenously induced electric fields to the efficacy of those fields to inhibit immobilization induced bone loss in an in vivo model of skeletal adaptation. Analysis of ...

The COSS analysis suggested by Berg [B. G. Berg, J. Acoust. Soc. Am. 86, 1743-1746 (1989)] is applied to a profile listening task. The listener's task is to detect an increment in the level of the middle component of an n-component spectrum. The overall level of the components is randomly ...

The threshold for a signal masked by a narrow band of noise centered at the signal frequency (the on-frequency band) may be reduced by adding to the masker a second band of noise (the flanking band) whose envelope is correlated with that of the first band, an effect called comodulation ...

Comodulation detection differences (CDDs) were studied using flanking bands that were either gated simultaneously with the signal band (burst) or gated at varying times prior to signal onset (fringed). Used for these experiments were a signal band centered at 1250 Hz and four flanking bands centered at 450, 850, 1650, ...

Comodulation masking release (CMR) was investigated as a function of signal frequency (0.5-4.0 kHz) and the total bandwidth of noise centered on the signal frequency. Taking noncomodulated noise of the same bandwidth as the reference condition, CMR for modulated noise increased with increasing bandwidth of the flanking noise outside the ...

The detectability of a pure-tone signal masked by a band of noise centered on the signal can be improved by the addition of flanking noise bands, provided that the temporal envelopes of the flanking bands are correlated with that of the on-signal band. This phenomenon is referred to as comodulation ...

This article presents the results of two experiments investigating performance on a monaural envelope correlation discrimination task. Subjects were asked to discriminate pairs of noise bands that had identical envelopes (referred to as correlated stimuli) from pairs of noise bands that had envelopes which were independent (uncorrelated stimuli). In the ...

Stimuli of random intensities and various but predictable frequencies were presented for repeated magnitude estimations on the same scale (mixed-frequency scaling). The frequencies for a particular judgment session were selected so that they lay either inside each other's critical bands or outside them. Contrastive dependencies of current magnitude estimation responses ...

We have developed and tested several detectors of local activations in unipolar cardiac electrograms; the detectors are based on the frequency content of the waveforms. For this study, myocardial regions with no local electrical activity were created with cryoablation in canine ventricles, so that the characteristics of electrograms reflecting local ...

NoSo and NoS pi detection thresholds for a 500-Hz pure-tone signal were measured as a function of masking noise bandwidth in normal-hearing and cochlear hearing-impaired subjects. NoSo and NoS pi critical bands were derived from the bandlimited noise functions. A notched noise measure of the monaural critical band was also ...

Day-old chicks were exposed for 0.5 h to overhead lighting ('primed') and then imprinted by exposing them for 90 min to a rotating red box. The chicks were otherwise maintained in darkness. Immediately after training these chicks (n = 16), together with 16 primed and 16 dark-reared controls were killed. ...

Detection thresholds were determined for signals consisting of one, two, or five noise bands embedded in eight "cue" bands. All of the noise bands were 100 Hz wide. The center frequencies of the signal bands ranged from 1250-3250 Hz in 500-Hz steps, and those of the cue bands ranged from ...

Comodulation masking release for a 700-Hz pure-tone signal was investigated as a function of the number and spectral positions of 20-Hz-wide comodulated flanking bands. In the first experiment, all stimuli were presented diotically. CMR was examined as a function of the number of flanking bands present, in conditions where the ...

Minimum-detectable gaps for sinusoidal stimuli were measured for three users of a multi electrode cochlear prosthesis as functions of stimulus level, frequency, and electrode place within the cochlea. Stimulus level was scaled by sensation level and by growth-of-loudness functions generated for each condition by direct magnitude estimation. Minimum-detectable gaps decreased ...

Visual processing was investigated in judgments of relative line position. Stimulus continua were generated by bisecting a straight line and displacing the segments. Experiment 1 measured discrimination of pairs of longitudinally displaced segments at equal steps along the continuum. At long (2 s) durations discrimination fell smoothly, but at short ...

Masked thresholds for octave-band noises with center frequencies of 0.4, 1, 2, 4, and 10 kHz and for a 1/3-octave-band noise centered at 10 kHz were obtained from listeners 6.5 months to 20.5 years of age at two levels of a broadband masker (0 and 10 dB/cycle). Thresholds declined exponentially ...

Gap detection was measured as a function of noise bandwidth with constant high-frequency cutoff in both normal-hearing and cochlear-impaired listeners. Band-widening functions were measured in a low-frequency region (0.6-kHz upper cutoff) and a high-frequency region (2.2-kHz upper cutoff). Measures of frequency selectivity were also obtained in the two frequency regions. ...

The detectability of tones, or of intensity increments to tones, in bands of random noise was measured for conditions in which the overall level was fixed or was randomly roved from interval to interval of every experimental trial. The purpose of the within-trial rove was to limit the usefulness of ...

The ability of human observers to detect partially filled or completely silent intervals (gaps) was measured using a variety of different waveforms. The slopes of the psychometric functions for gap detection using broadband noise are dependent upon the amount of noise remaining during the gap. For completely silent intervals, the ...

Gap detection thresholds were measured in patients with the Nucleus and Symbion cochlear implants as a function of several current waveform parameters. Detection of gaps in an electrical sinusoidal stimulus or in a train of biphasic pulses by implanted patients was similar to detection of gaps in comparable acoustic stimuli ...

Light-dependent regulation of cell cycle progression in the marine cyanobacterium Synechococcus strain WH-8101 was demonstrated through the use of flow cytometry. Our results show that, similar to eucaryotic cells, marine Synechococcus spp. display two gaps in DNA synthesis, at the beginning and at the end of the cell cycle. Progression ...

The ability of subjects to detect and discriminate spectral peaks and notches in noise stimuli was determined for center frequencies fc of 1 and 8 kHz. The signals were delivered using an insert earphone designed to produce a flat frequency response at the eardrum for frequencies up to 14 kHz. ...

Chromatic discrimination was studied with two half-fields that were either precisely juxtaposed or were separated by a narrow gap. When present, the gap was in some conditions filled with light isoluminant to the test fields. When the fields were juxtaposed, chromatic sensitivity declined with viewing duration. For a discrimination based ...

Although discriminable changes in stimulus energy or overall duration may accompany the silent temporal gap, there is little evidence that these extraneous cues confound the measurement of temporal gap detection threshold. In this report we show that (1) under conditions where gap detection thresholds are large in relation to the ...

The threshold for a signal masked by a narrow band of noise centered at the signal frequency (the on-frequency band) may be reduced by adding to the masker a second band of noise (the flanking band) whose envelope is correlated with that of the first band. This effect is called ...

When very brief tonal signals are presented immediately after the onset of a gated noise masker, detectability can be 10-20 dB worse than when the signal is delayed by several hundred milliseconds, an effect known as the overshoot. It has long been known that, when an "onset" is created in ...

Signal detection was determined in conditions where the masker was a 10-Hz-wide noise band centered on the signal, and in conditions where either a comodulated or noncomodulated noise band (centered at 0.8 times the signal frequency) was also present. Signal frequencies of 500 or 2000 Hz were investigated. In one ...

The ability of listeners to discriminate between simultaneously presented bands of noise whose envelopes were either the same or statistically independent was determined. Bands of 100-Hz wide noise were employed which had low and high center frequencies of (2500, 2750), (2500, 3000), (2500, 3500) and (4000, 4400) Hz. Average discriminations ...

Analysis of laboratory spectra of numerous astrophysical ice analogs demonstrates that the exact band position, width, and profile of the solid state CO fundamental near 2137 cm-1 (4.679 microns) can provide important information on the physical conditions present during the ice accretion phase as well as during any subsequent thermal ...

Dynamic images of individual signs of American Sign Language (ASL) with a resolution of 96 X 64 pixels were bandpass filtered in adjacent frequency bands. Intelligibility was determined by testing deaf subjects fluent in ASL. The following results were obtained. (1) By iteratively varying the center frequencies and bandwidths of ...

Average long-term RMS 1/3-octave band speech spectra were generated for 30 male and 30 female talkers. The two spectra were significantly different in both low and high frequency bands but were similar in the mid-frequency region. It was concluded that a single spectrum could validly be used to represent both ...

Thresholds for the detection of temporal gaps were measured using two types of signals to mark the gaps: bandpass-filtered noises and sinusoids. The first experiment used seven subjects with relatively flat unilateral moderate cochlear hearing loss. The normal ear of each subject was tested both at the same sound-pressure level ...

Detection of signals composed of one, two, or three pure-tone components was examined in comodulated and noncomodulated masking noises. The masking noise was either a single 30-Hz-wide narrow band of noise, two narrow bands of noise, or three narrow bands of noise. Comodulation masking release (CMR) was greatest when (1) ...

The spatial transfer functions (STF) of L-type horizontal cells (HC) in turtle retina were measured using drifting sine wave grafting stimuli. Two classes of STF were identified: low-pass and band-pass. A low-pass STF corresponds to a linespread function (LSF) having an excitatory center that attenuates monotonically with distance; a band-pass ...