Effects of temporal asynchrony and stimulus magnitude on competitive audio–visual binding

We present a sceptical view of multimodal multistability—drawing most of our examples from the relation between audition and vision. We begin by summarizing some of the principal ways in which audio-visual binding takes place. We review the evidence that unambiguous stimulation in one modality may affect the perception of a multistable stimulus in another modality. Cross-modal influences of one multistable stimulus on the multistability of another are different: they have occurred only in speech perception. We then argue that the strongest relation between perceptual organization in vision and perceptual organization in audition is likely to be by way of analogous Gestalt laws. We conclude with some general observations about multimodality.

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An examination of the variables that affect express saccade generation

Visual Neuroscience ◽

10.1017/s0952523804042038 ◽

2004 ◽

Vol 21 (2) ◽

pp. 119-127 ◽

Cited By ~ 10

Author(s):

PETER H. SCHILLER ◽

JOHANNES HAUSHOFER ◽

GEOFFERY KENDALL

Keyword(s):

Rhesus Monkeys ◽

Target Onset ◽

Express Saccades ◽

Express Saccade ◽

Saccadic System ◽

Fixation Spot ◽

Temporal Asynchrony ◽

Saccade Generation ◽

Gap Time

The frequency with which express saccades are generated under a variety of conditions in rhesus monkeys was examined. Increasing the gap time between fixation spot termination and target onset increased express saccade frequency but was progressively less effective in doing so as the number of target positions in the sample was increased. Express saccades were rarely produced when two targets were presented simultaneously and the choice of either of which was rewarded; a temporal asynchrony of only 17 ms between the targets reinstated express saccade generation. Express saccades continued to be generated when the vergence or pursuit systems was coactivated with the saccadic system.

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Are the dynamic response characteristics of brachial artery flow-mediated dilation sensitive to the magnitude of increase in shear stimulus?

Journal of Applied Physiology ◽

10.1152/japplphysiol.01190.2007 ◽

2008 ◽

Vol 105 (1) ◽

pp. 282-292 ◽

Cited By ~ 50

Author(s):

K. E. Pyke ◽

J. A. Hartnett ◽

M. E. Tschakovsky

Keyword(s):

Shear Stress ◽

Shear Rate ◽

Dynamic Response ◽

Phase I ◽

Brachial Artery ◽

Flow Mediated Dilation ◽

Final Phase ◽

Stimulus Magnitude ◽

Brachial Artery Diameter ◽

Response Characteristics

The purpose of this study was to determine the dynamic characteristics of brachial artery dilation in response to step increases in shear stress [flow-mediated dilation (FMD)]. Brachial artery diameter (BAD) and mean blood velocity (MBV) (Doppler ultrasound) were obtained in 15 healthy subjects. Step increases in MBV at two shear stimulus magnitudes were investigated: large (L; maximal MBV attainable), and small (S; MBV at 50% of the large step). Increase in shear rate (estimate of shear stress: MBV/BAD) was 76.8 ± 15.6 s−1 for L and 41.4 ± 8.7 s−1 for S. The peak %FMD was 14.5 ± 3.8% for L and 5.7 ± 2.1% for S ( P < 0.001). Both the L (all subjects) and the S step trials (12 of 15 subjects) elicited a biphasic diameter response with a fast initial phase (phase I) followed by a slower final phase. Relative contribution of phase I to total FMD when two phases occurred was not sensitive to shear rate magnitude ( r2 = 0.003, slope P = 0.775). Parameters quantifying the dynamics of the FMD response [time delay (TD), time constant (τ)] were also not sensitive to shear rate magnitude for both phases (phase I: TD r2 = 0.03, slope P = 0.376, τ r2 = 0.04, slope P = 0.261; final phase: TD r2 = 0.07, slope P = 0.169, τ r2 = 0.07, slope P = 0.996). These data support the existence of two distinct mechanisms, or sets of mechanisms, in the human conduit artery FMD response that are proportionally sensitive to shear stimulus magnitude and whose dynamic response is not sensitive to shear stimulus magnitude.

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When combined spatial polarities activated through spatio-temporal asynchrony lead to better mathematical reasoning for addition

Memory & Cognition ◽

10.3758/s13421-018-0831-7 ◽

2018 ◽

Vol 46 (7) ◽

pp. 1194-1209

Author(s):

Hélène Verselder ◽

Nicolas Morgado ◽

Sébastien Freddi ◽

Vincent Dru

Keyword(s):

Mathematical Reasoning ◽

Temporal Asynchrony ◽

Spatio Temporal

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Development of sensitivity to audiovisual temporal asynchrony during midchildhood.

Developmental Psychology ◽

10.1037/dev0000073 ◽

2016 ◽

Vol 52 (2) ◽

pp. 232-241 ◽

Cited By ~ 7

Author(s):

Natalya Kaganovich

Keyword(s):

Temporal Asynchrony

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Limitations of Proposed Signatures of Bayesian Confidence

Neural Computation ◽

10.1162/neco_a_01141 ◽

2018 ◽

Vol 30 (12) ◽

pp. 3327-3354 ◽

Cited By ~ 11

Author(s):

William T. Adler ◽

Wei Ji Ma

Keyword(s):

Bayesian Model ◽

Posterior Probability ◽

Model Comparison ◽

Sufficient Conditions ◽

Internal Noise ◽

Quantitative Model ◽

Alternative Form ◽

Stimulus Magnitude ◽

Animal Data ◽

Average Confidence

The Bayesian model of confidence posits that confidence reflects the observer's posterior probability that the decision is correct. Hangya, Sanders, and Kepecs ( 2016 ) have proposed that researchers can test the Bayesian model by deriving qualitative signatures of Bayesian confidence (i.e., patterns that one would expect to see if an observer were Bayesian) and looking for those signatures in human or animal data. We examine two proposed signatures, showing that their derivations contain hidden assumptions that limit their applicability and that they are neither necessary nor sufficient conditions for Bayesian confidence. One signature is an average confidence of 0.75 on trials with neutral evidence. This signature holds only when class-conditioned stimulus distributions do not overlap and when internal noise is very low. Another signature is that as stimulus magnitude increases, confidence increases on correct trials but decreases on incorrect trials. This divergence signature holds only when stimulus distributions do not overlap or when noise is high. Navajas et al. ( 2017 ) have proposed an alternative form of this signature; we find no indication that this alternative form is expected under Bayesian confidence. Our observations give us pause about the usefulness of the qualitative signatures of Bayesian confidence. To determine the nature of the computations underlying confidence reports, there may be no shortcut to quantitative model comparison.

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