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G ten Hoopen

Publications and source records attributed to G ten Hoopen.

13 recordsLinked to original sources
PubMed1992

Time-shrinking: a discontinuity in the perception of auditory temporal patterns.

Recent research at our laboratories in the field of human auditory time perception revealed that the duration of short empty time intervals (less than approximately 200 msec) is considerably underestimated if they are immediately preceded by shorter time intervals. Within a certain range, the amount of subjective time shrinking is a monotonous function of the preceding time interval; the shorter it is, the more it shrinks its successor. In the present study, the preceding interval was kept constant at 50 msec, and the following interval, for which the duration had to be judged, varied from 40 to 280 msec. The results showed that at up to 100 msec, the perceived duration increased to a much lesser extent than did the objective duration. Beyond 120 msec, the perceived duration quickly increased and reached a veridical value at 160 msec. Such a sudden change of perceived duration in a temporal pattern in which the objective duration varies gradually indicates a typical example of categorical perception. We suggest that such a categorization of the time dimension might be a clue for processes of speech and music perception.

Attention↗
PubMed1983

Auditory spatial alternation transforms auditory time.

Recent research has shown that a sequence of auditory events that is alternated between the ears is stretched out in auditory memory, as compared with nonalternating sequences. Although the stimulus-onset asynchronies (SOAs) of the interaural and monaural sequences were the same, the perceptual-onset asynchronies (POAs) differed by 24 msec. Because this result was only established for a restricted range of SOAs (125-250 msec), the present study tested a much larger range (40-2,130 msec). It turned out that the POA difference of 25 msec remained invariant over this whole range. Furthermore it was investigated how the angle of alternation affected the POA difference. It was found that (a) this difference increased linearly with increasing angular separation, and (b) the effects of SOA and angular separation on the POA difference were additive. The merits of six different attention-switching models were inspected to explain these results, but none of the models could describe the effects satisfactorily. We offer a new model, the space-time network, that copes not only with the present results but also explains several other studies reported in the literature.

Attention↗
PubMed1982

Interaural and monaural clicks and clocks: tempo difference versus attention switching.

We describe a quantitative model capable of explaining the results of all reported investigations of the counting of interaural and monaural click sequencies. The model is developed by means of three convergent operations: (a) reanalyzing absolute-estimation data of apparent repetition rates of interaural and monaural sequences, (b) deriving interaural and monaural counting times from numerosity-judgement data, and (c) analyzing the time that observers needed to respond to the end of interaural and monaural sequences. The combined evidence demonstrates that the perceived onset asynchrony (POA) between interaural events is 24 msec longer than that between monaural events. The model has three components: (a) a "stimulus clock," which represents the stimulus onset synchrony (SOA) between events; (b) a "memory clock," which represents the POA between events, and (c) a "counting clock," which represents the counter increment time. The transfer functions between the three clocks are deduced from empirical data. Other proposals to explain interaural click counting results (attention switching, streaming by locus, counterincrement deficit) are discussed and rejected.

Attention↗
PubMed1981

Attention switching and patterns of sound locations in counting clicks.

The present study investigates the process of auditory attention switching by means of experiments in which observers counted the number of monaurally and interaurally presented clicks. Several studies have reported that the number of interaurally presented events was underestimated relative to monaurally presented ones. Ten Hoopen and Vos, however, could not replicate this phenomenon. The data from Experiment 1 demonstrate that such a discrepancy is caused by the different orders in which the monaural and interaural sequences were presented. With blocked presentation, interaural sequences were counted less well than monaural sequences, whereas there was no difference when all sequence types were randomized. An attention-switching mechanism was proposed to account for performance on interaural sequences during blocked presentation. In the random case observers presumably did not switch their attention to and fro, but "multiplexed" the channels. Experiment 2 investigated whether observers can deliberately suppress the process of attention switching when confronted with blocked interaural sequences. The results show that they cannot, which suggests that attention switching is an automatic process.

Adult↗
PubMed1980

Attention switching is not a fatigable process: methodological comments on Axelrod and Guzy (1972).

Guzy and Axelrod investigated auditory attention switching by means of the click-counting paradigm and concluded that attention switching is a fatigable process. In the present comment it is shown that this conclusion is based on a faulty analysis of the data: The scores subjected to the analysis of variance were transformed such that they were no longer linear combinations of the factorial effects. Reanalyzing the data in the correct way renders perfectly linear conting functions that deviate from theoretical fatigue functions. It is concluded that the attention-switching mechanism is not fatigable.

Attention↗