Judgments of synchrony between auditory and moving or still visual stimuli.

The flash-lag effect is a visual illusion wherein intermittently flashed, stationary stimuli seem to trail after a moving visual stimulus despite being flashed synchronously. We tested hypotheses that the flash-lag effect is due to spatial extrapolation, shortened perceptual lags, or accelerated acquisition of moving stimuli, all of which call for an earlier awareness of moving visual stimuli over stationary ones. Participants judged synchrony of a click either to a stationary flash of light or to a series of adjacent flashes that seemingly bounced off or bumped into the edge of the visual display. To be judged synchronous with a stationary flash, audio clicks had to be presented earlier--not later--than clicks that went with events, like a simulated bounce (Experiment 1) or crash (Experiments 2-4), of a moving visual target. Click synchrony to the initial appearance of a moving stimulus was no different than to a flash, but clicks had to be delayed by 30-40 ms to seem synchronous with the final (crash) positions (Experiment 2). The temporal difference was constant over a wide range of motion velocity (Experiment 3). Interrupting the apparent motion by omitting two illumination positions before the last one did not alter subjective synchrony, nor did their occlusion, so the shift in subjective synchrony seems not to be due to brightness contrast (Experiment 4). Click synchrony to the offset of a long duration stationary illumination was also delayed relative to its onset (Experiment 5). Visual stimuli in motion enter awareness no sooner than do stationary flashes, so motion extrapolation, latency difference, and motion acceleration cannot explain the flash-lag effect.     

Effect of stimulus pulse duration and interstimulus interval on cross-modal matching of auditory and lingual vibrotactile stimuli

Cross-modal matching functions for eight intensity levels of a 1000-Hz auditory stimulus and a 250-Hz lingual vibrotactile stimulus were obtained for two groups of subjects. Group 1 adjusted the vibrotactile stimulus to match the auditory stimulus, and Group 2 adjusted the auditory stimulus to match the vibrotactile stimulus. Stimulus-pulse durations and interstimulus intervals were varied over six experimental conditions for both groups. The variations in stimulus-pulse durations and interstimulus intervals had no appreciable effect on mean matching-function exponents for the two groups. A possible regression effect consistent with data from other psychophysical scaling studies was noted for matching functions of the two stimuli.     

Rehearsal of visual and auditory stimuli while shadowing.

Memory trigrams were presented by one of three methods: visual-concurrent (all three letters appeared simultaneously), visual-successive, and auditory-successive. During the 12-sec retention interval, subjects shadowed and reported their rehearsals and mnemonic associations via switches. On trials without associations, recall performance was interpreted as support for the hypothesis that the form of rehearsal is related to presentation modality. However, the frequency and temporal patterning of the rehearsals over the retention interval were virtually identical for all three presentation conditions, suggesting that the "control processes" were relatively independent of both method of presentation and modality of rehearsal. Most importantly, these data in combination with earlier data suggest that the efficiency of each rehearsal was also independent of those same factors, in each case quite comparable to that of a concurrent visual stimulus.     

The effect of brief auditory stimuli on visual apparent motion

When two discrete stimuli are presented in rapid succession, observers typically report a movement of the lead stimulus toward the lag stimulus. The object of this study was to investigate crossmodal effects of irrelevant sounds on this illusion of visual apparent motion. Observers were presented with two visual stimuli that were temporally separated by interstimulus onset intervals from 0 to 350 ms. After each trial, observers classified their impression of the stimuli using a categorisation system. The presentation of short sounds intervening between the visual stimuli facilitated the impression of apparent motion relative to baseline (visual stimuli without sounds), whereas sounds presented before the first and after the second visual stimulus as well as simultaneously presented sounds reduced the motion impression. The results demonstrate an effect of the temporal structure of irrelevant sounds on visual apparent motion that is discussed in light of a related multisensory phenomenon, 'temporal ventriloquism', on the assumption that sounds can attract lights in the temporal dimension.     

Effect of intensity of visual stimulation on auditory sensitivity in relation to personality

Auditory thresholds were determined by a modified method of limits under 10 intensities of light (patterned or homogeneous). An analysis of variance of the data showed significant results for intensity conditions, personality type and the interaction of these parameters. Auditory sensitivity increased under weak, and decreased under strong, intensities of light in introverts. It increased under all intensities in extraverts, with greater increase at greater intensities, and increased under weak and medium intensities in ambiverts. The EPI E, but not N, scale scores and sensitivity increases correlated positively, at medium and strong intensities of light.     

The effect of various heteromodal stimuli on visual sensitivity

Ten experiments are reported. In each the effect of a heteromodal stimulus on visual sensitivity is investigated. With one exception all the stimuli produced a small increase in visual sensitivity. A number of possible explanations of intersensory facilitation are considered.     

Comparisons of memory for nonverbal auditory and visual sequential stimuli

Properties of auditory and visual sensory memory were compared by examining subjects' recognition performance of randomly generated binary auditory sequential frequency patterns and binary visual sequential color patterns within a forced-choice paradigm. Experiment 1 demonstrated serial-position effects in auditory and visual modalities consisting of both primacy and recency effects. Experiment 2 found that retention of auditory and visual information was remarkably similar when assessed across a 10 s interval. Experiments 3 and 4, taken together, showed that the recency effect in sensory memory is affected more by the type of response required (recognition vs. reproduction) than by the sensory modality employed. These studies suggest that auditory and visual sensory memory stores for nonverbal stimuli share similar properties with respect to serial-position effects and persistence over time.     

Comparing auditory vs visual stimuli in the tip-of-the-tongue phenomenon

An experiment is reported comparing the effectiveness of auditory and visual stimuli in eliciting the tip-of-the-tongue phenomenon. 30 participants were asked to name the titles of 27 television shows. Half of the participants were given segments of the theme song for each show (auditory cue), and half were shown the cast photographs for each show (visual cue). Participants were asked to report whenever they experienced the tip-of-the-tongue state. There were no significant differences between the auditory and visual stimuli in terms of the incidence rate for the tip-of-the-tongue state, the amount of partial information that participants provided in their responses, or the frequency of interlopers (alternative responses that persistently come to mind). These findings suggest that the characteristics of the tip-of-the-tongue state are determined more by the nature of the response set than by the type of stimuli used as cues. The results are inconsistent with inferential theories of the tip-of-the-tongue phenomenon, such as the cue familiarity hypothesis and, instead, tend to support direct-access hypotheses.     

Discontinuity in the enumeration of sequentially presented auditory and visual stimuli

The seeking of discontinuity in enumeration was recently renewed because Cowan [Cowan, N. (2001). The magical number 4 in short-term memory: A reconsideration of mental storage capacity. Behavioral and Brain Sciences, 24, 87–185; Cowan, N. (2005). Working memory capacity. Hove: Psychology Press] suggested that it allows evaluating the limit of the focus of attention, currently estimated at four items. A strong argument in favour of a general constraint of the cognitive system is that similar discontinuities should be observed in modalities different from the classic simultaneous presentation of visual objects. Recently, data were provided on tactile stimuli, but the authors diverged in their conclusion about the existence of such discontinuity [Gallace, A., Tan, H. Z., & Spence, C. (2006). Numerosity judgments for tactile stimuli distributed over the body surface. Perception, 35(2), 247–266; Riggs, K. J., Ferrand, L., Lancelin, D., Fryziel, L., Dumur, G., & Simpson, A. (2006). Subitizing in tactile perception. Psychological Science, 17(4), 271–272]. Following a similar rationale, our study aimed at evaluating discontinuity in the enumeration of auditory and visual stimuli presented sequentially. The clear and similar discontinuity observed in error rates, response times and given responses for both modalities favours the general capacity limit view, but also questions the size of this capacity, because the discontinuity occurred here at size 2. However, the masking of stimuli in sensory memory could not be entirely discarded.     

STIVID: A VBSCRIPT-based program for adding visual and auditory stimuli on videotapes

Some psychological experiments require placement of visual and auditory stimuli on predefined frames in a videotape. We introduce STIVID (STImuli on VIDeo) as a method of performing this task. STIVID can add images, words, simple shapes, and audio tones to specific frames of existing video files created in AVI format. STIVID is written in Visual Basic and uses VBScripts to modify the AVI files. Three applications of this program are discussed: adding stimuli for reaction time experiments with couples watching a relational conflict, use of distractors in ADHD experiments, and placing eye masks on actors in existing videotapes to manipulate perceptibility of the target’s facial expression during the mind-reading process.     

An adjusting avoidance procedure with multiple auditory and visual warning stimuli

Male albino rats were trained on an adjusting avoidance schedule in which each lever press accumulated a given amount of shock-free time. Multiple auditory and visual stimuli were programmed for each discrete temporal distance from the shock in an effort to place the avoidance behavior under the control of the shock proximity. The effects of the stimuli were further examined by presenting part of them and then by removing them altogether. With the combined auditory and visual stimuli, the rat spent most of the time relatively close to the shock and usually started to respond only when the shock was near. With the visual stimuli only, the rat kept the shock at intermediate temporal distances and responded more variably. The behavior with the auditory stimuli alone was quite similar to that produced by the combined stimuli, thus indicating that the auditory stimuli exercised the greater control. When all stimuli were removed, the animal usually kept the shock as far away as the procedure permitted. When only a single pre-shock stimulus was presented, the rat remained quite close to the shock and started to respond predominantly in the pre-shock step.     

Action enhances auditory but not visual temporal sensitivity

People naturally dance to music, and research has shown that rhythmic auditory stimuli facilitate production of precisely timed body movements. If motor mechanisms are closely linked to auditory temporal processing, just as auditory temporal processing facilitates movement production, producing action might reciprocally enhance auditory temporal sensitivity. We tested this novel hypothesis with a standard temporal-bisection paradigm, in which the slope of the temporal-bisection function provides a measure of temporal sensitivity. The bisection slope for auditory time perception was steeper when participants initiated each auditory stimulus sequence via a keypress than when they passively heard each sequence, demonstrating that initiating action enhances auditory temporal sensitivity. This enhancement is specific to the auditory modality, because voluntarily initiating each sequence did not enhance visual temporal sensitivity. A control experiment ruled out the possibility that tactile sensation associated with a keypress increased auditory temporal sensitivity. Taken together, these results demonstrate a unique reciprocal relationship between auditory time perception and motor mechanisms. As auditory perception facilitates precisely timed movements, generating action enhances auditory temporal sensitivity.     

On the processing of simple visual and auditory stimuli at distinct levels

Two RT studies explored the possibility that identification of a single stimulus can take place through more than one perceptual route. In the first experiment, mean RT to color was systematically changed by varying type of catch stimulus. In the second experiment, the form of the RT distribution to a tone was changed by varying type of catch stimulus. Considerations of distribution means and shapes led to the conclusion that detection and discrimination are two of the alternative levels of perceptual processing which can be evoked in rapid identification of these stimuli.     

Stimulus compatibility effects of an accessory visual stimulus on auditory sensitivity

Studies have reported that an accessory stimulus in a second modality can have a facilitative effect on sensory detection in a primary modality. However, performance declines when the subject has the additional task of reporting on the accessory stimulus. The facilitative effect has been attributed to an arousal or warning process, while the interference effect has been characterized as a result of limited channel capacity. Auditory sensitivity was assessed under accessory visual stimulation. Visual stimulus intensity (arousal), processing demand, and interstimulus compatibility (same or opposite direction of change of primary and secondary stimuli) were manipulated. The results indicated that interstimulus compatibility, not arousal, accounted for the obtained facilitation effect. Interference due to additional task demands was not observed. It was proposed that the facilitation effect was due to selective sensory encoding.