A Comparison of the Effects of Differences in Temporal Gating and Ear of Presentation on Profile Discrimination

Nicholas I Hill; Peter J Bailey

doi:10.1068/p3124

A Comparison of the Effects of Differences in Temporal Gating and Ear of Presentation on Profile Discrimination

Perception ◽

10.1068/p3124 ◽

2002 ◽

Vol 31 (11) ◽

pp. 1395-1402

Author(s):

Nicholas I Hill ◽

Peter J Bailey

Keyword(s):

Spatial Location ◽

Target Component ◽

Frequency Components ◽

Dichotic Presentation

The aim of the study was to examine the effects of differences in temporal gating and ear of presentation (both separately and in combination) on listeners' ability to detect an increment in the level of a 1 kHz component (the target) relative to that of four spectrally flanking components. The flanking components were always presented to the listeners' right ear, while the target component was either presented to the same ear (monaural presentation) or to the left ear (dichotic presentation). Similarly, the target and flanking components were either gated on and off at the same time (synchronous presentation), or else the target component began 100 ms before and terminated 100 ms after the four flanking components (asynchronous presentation). On average, thresholds were lowest in the synchronous, monaural condition, and highest in the two asynchronous conditions. Ear differences alone did result in elevated thresholds for most listeners. However, combining differences in gating and ear of presentation produced thresholds that were indistinguishable from those obtained when gating differences alone were employed. These results are consistent with the suggestion that differences in temporal gating lead to more complete segregation of concurrent frequency components than differences in spatial location.

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Simulations of high-resolution images of amorphous silicon films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010014419x ◽

1986 ◽

Vol 44 ◽

pp. 544-545

Author(s):

G. Y. Fan ◽

J. M. Cowley

Keyword(s):

Electron Microscope ◽

High Frequency ◽

Fourier Transformation ◽

Amorphous Materials ◽

Low Frequency ◽

Chromatic Aberration ◽

Structure Information ◽

Frequency Components ◽

High Resolution Images ◽

Spatial Frequency Spectrum

It is well known that the structure information on the specimen is not always faithfully transferred through the electron microscope. Firstly, the spatial frequency spectrum is modulated by the transfer function (TF) at the focal plane. Secondly, the spectrum suffers high frequency cut-off by the aperture (or effectively damping terms such as chromatic aberration). While these do not have essential effect on imaging crystal periodicity as long as the low order Bragg spots are inside the aperture, although the contrast may be reversed, they may change the appearance of images of amorphous materials completely. Because the spectrum of amorphous materials is continuous, modulation of it emphasizes some components while weakening others. Especially the cut-off of high frequency components, which contribute to amorphous image just as strongly as low frequency components can have a fundamental effect. This can be illustrated through computer simulation. Imaging of a whitenoise object with an electron microscope without TF limitation gives Fig. 1a, which is obtained by Fourier transformation of a constant amplitude combined with random phases generated by computer.

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Dynamic Visual Noise Affects Visual Short-Term Memory for Surface Color, but not Spatial Location

Experimental Psychology (formerly Zeitschrift für Experimentelle Psychologie) ◽

10.1027/1618-3169/a000003 ◽

2010 ◽

Vol 57 (1) ◽

pp. 17-26 ◽

Cited By ~ 19

Author(s):

Kevin Dent

Keyword(s):

Short Term Memory ◽

Spatial Location ◽

Visual Noise ◽

Dynamic Visual Noise ◽

Short Term ◽

Surface Color ◽

Term Memory ◽

Visual Short Term Memory ◽

Experimental Tool ◽

Spatial Locations

In two experiments participants retained a single color or a set of four spatial locations in memory. During a 5 s retention interval participants viewed either flickering dynamic visual noise or a static matrix pattern. In Experiment 1 memory was assessed using a recognition procedure, in which participants indicated if a particular test stimulus matched the memorized stimulus or not. In Experiment 2 participants attempted to either reproduce the locations or they picked the color from a whole range of possibilities. Both experiments revealed effects of dynamic visual noise (DVN) on memory for colors but not for locations. The implications of the results for theories of working memory and the methodological prospects for DVN as an experimental tool are discussed.

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Multiple-Object Tracking

Experimental Psychology (formerly Zeitschrift für Experimentelle Psychologie) ◽

10.1027/1618-3169/a000085 ◽

2011 ◽

Vol 58 (3) ◽

pp. 196-200 ◽

Cited By ~ 15

Author(s):

K. Botterill ◽

R. Allen ◽

P. McGeorge

Keyword(s):

Object Tracking ◽

Cognitive Processes ◽

Spatial Location ◽

Multiple Object Tracking ◽

Tracking Performance ◽

Multiple Object

The Multiple-Object Tracking paradigm has most commonly been utilized to investigate how subsets of targets can be tracked from among a set of identical objects. Recently, this research has been extended to examine the function of featural information when tracking is of objects that can be individuated. We report on a study whose findings suggest that, while participants can only hold featural information for roughly two targets this task does not affect tracking performance detrimentally and points to a discontinuity between the cognitive processes that subserve spatial location and featural information.

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