scholarly journals Perceptual separation of changes in lighting and reflectance can be supported by specularity

2012 ◽  
Vol 12 (14) ◽  
pp. 12-12
Author(s):  
R. Lee ◽  
H. Smithson
Keyword(s):  
Perceptual Separation

The Effect of Nonlinear Amplitude Growth on the Speech Perception Benefits Provided by a Single-Sided Vocoder

2019 ◽  
Vol 62 (3) ◽  
pp. 745-757 ◽  
Author(s):  
Jessica M. Wess ◽  
Joshua G. W. Bernstein
Keyword(s):  
Transfer Functions ◽  
Spatial Configuration ◽  
Free Field ◽  
Spatial Separation ◽  
Compression And Expansion ◽  
Interaural Difference ◽  
Interaural Differences ◽  
Single Sided Deafness ◽  
Perceptual Separation ◽  
Loudness Growth

PurposeFor listeners with single-sided deafness, a cochlear implant (CI) can improve speech understanding by giving the listener access to the ear with the better target-to-masker ratio (TMR; head shadow) or by providing interaural difference cues to facilitate the perceptual separation of concurrent talkers (squelch). CI simulations presented to listeners with normal hearing examined how these benefits could be affected by interaural differences in loudness growth in a speech-on-speech masking task.MethodExperiment 1 examined a target–masker spatial configuration where the vocoded ear had a poorer TMR than the nonvocoded ear. Experiment 2 examined the reverse configuration. Generic head-related transfer functions simulated free-field listening. Compression or expansion was applied independently to each vocoder channel (power-law exponents: 0.25, 0.5, 1, 1.5, or 2).ResultsCompression reduced the benefit provided by the vocoder ear in both experiments. There was some evidence that expansion increased squelch in Experiment 1 but reduced the benefit in Experiment 2 where the vocoder ear provided a combination of head-shadow and squelch benefits.ConclusionsThe effects of compression and expansion are interpreted in terms of envelope distortion and changes in the vocoded-ear TMR (for head shadow) or changes in perceived target–masker spatial separation (for squelch). The compression parameter is a candidate for clinical optimization to improve single-sided deafness CI outcomes.

Role of Fundamental Frequency Differences in the Perceptual Separation of Competing Vowel Sounds by Listeners With Normal Hearing and Listeners With Hearing Loss

1997 ◽  
Vol 40 (6) ◽  
pp. 1434-1444 ◽  
Author(s):  
Kathryn Hoberg Arehart ◽  
Catherine Arriaga King ◽  
Kelly S. McLean-Mudgett
Keyword(s):  
Hearing Loss ◽  
Fundamental Frequency ◽  
Normal Hearing ◽  
Average Increase ◽  
Identification Task ◽  
Vowel Identification ◽  
Overall Performance ◽  
The Mean ◽  
Perceptual Separation

This study compared the ability of listeners with normal hearing and listeners with moderate to moderately-severe sensorineural hearing loss to use fundamental frequency differences (ΔF 0 ) in the identification of monotically presented simultaneous vowels. Two psychophysical procedures, double vowel identification and masked vowel identification, were used to measure identification performance as a function of ΔF 0 (0 through 8 semitones) between simultaneous vowels. Performance in the double vowel identification task was measured by the percentage of trials in which listeners correctly identified both vowels in a double vowel. The masked vowel identification task yielded thresholds representing signal-to-noise ratios at which listeners could just identify target vowels in the presence of a masking vowel. In the double vowel identification task, both listeners with normal hearing and listeners with hearing loss showed significant ΔF 0 benefit: Between 0 and 2 semitones, listeners with normal hearing showed an 18.5% average increase in performance; listeners with hearing loss showed a 16.5% average increase. In the masked vowel identification task, both groups showed significant ΔF 0 benefit. However, the mean benefit associated with ΔF 0 differences in the masked vowel task was more than twice as large in listeners with normal hearing 9.4 dB) when compared to listeners with hearing loss (4.4 dB), suggesting less ΔF 0 benefit in listeners with hearing loss. In both tasks, overall performance of listeners with hearing loss was significantly worse than performance of listeners with normal hearing. Possible reasons for reduced ΔF 0 benefit and decreased overall performance in listeners with hearing loss include reduced audibility of vowel sounds and deficits in spectro-temporal processing.

Perceptual separation of transparent motion components: the interaction of motion, luminance and shape cues

2013 ◽  
Vol 230 (1) ◽  
pp. 71-86
Author(s):  
Andrew Isaac Meso ◽  
Szonya Durant ◽  
Johannes M. Zanker
Keyword(s):  
Transparent Motion ◽  
Perceptual Separation

scholarly journals Introduction

2010 ◽  
Vol 19 (2) ◽  
pp. 1-6
Author(s):  
Ullrich Kockel
Keyword(s):  
School Curriculum ◽  
German School ◽  
Long Time ◽  
The 1960S ◽  
Perceptual Separation ◽  
Relationship Of ◽  
The Relationship

Arguably, anthropologists have studied the relationship of ‘culture’ and ‘nature’ for a long time and from a broad range of perspectives. The close thematic connections between anthropology and ecology reach back well beyond Ernst Haeckel’s postulate of ecology as a distinct science in the 1860s. Social historians (e.g. Brunner 1956) have noted how the ‘old European economy’ of ‘the whole house’, where ‘culture’ and ‘nature’ were regarded as closely intertwined, has been replaced in the course of industrialisation and modernisation by increasing perceptual separation and indeed juxtaposition of the two spheres. In a sense, the culmination of that movement may be seen, for example, in the progressive ousting of an integrative Heimatkunde – the holistic study of localities and regions – from the German school curriculum since the 1960s.

Induced contrast asynchronies may be useful for luminance photometry

2004 ◽  
Vol 21 (3) ◽  
pp. 243-247 ◽  
Author(s):  
ARTHUR G. SHAPIRO ◽  
ANTHONY D'ANTONA ◽  
JARED B. SMITH ◽  
LINDSAY A. BELANO ◽  
JUSTIN P. CHARLES
Keyword(s):  
Phase Modulation ◽  
Luminance Level ◽  
The Other ◽  
Visual Effect ◽  
Physically Identical ◽  
Perceptual Separation ◽  
Modulated Light

Shapiro et al. (2004) introduced a new visual effect (the induced contrast asynchrony) that demonstrates a perceptual separation between the response to a modulated light and the response to contrast of the light relative to background. The effect is composed of two physically identical disks, one surrounded by a dark annulus and the other by a light annulus. The luminance levels of both central disks were modulated in time, producing a stimulus with in-phase luminance modulation and antiphase contrast modulation. Observers primarily perceived the disks to be modulating asynchronously (i.e. they perceived the contrast), but at low temporal frequencies could also track the luminance level. Here we document that the induced contrast asynchrony disappears when the surrounds are achromatic and the center lights are modulated near the equiluminant axis. Observers viewed 1-deg-diameter disks embedded 2-deg-diameter achromatic surrounds. The chromaticity of the disks was modulated in time (1 Hz) along lines in an S versus Luminance cardinal color plane and an L-M versus Luminance cardinal color plane; observers responded as to whether the modulation appeared in phase. For all observers and both color planes, the lights appeared in phase most frequently at angles near the standard observer's equiluminant line and out of phase at angles further away from that line. Observers differed in the range of angles that produce the appearance of in-phase modulation. The results suggest that induced contrast asynchronies may be useful as a technique for equating luminance of disparate lights.

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