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Biomedical subjects

S T Klapp

Publications and source records attributed to S T Klapp.

At least 19 recordsLinked to original sources

Tests of attentional flexibility in listening to polyrhythmic patterns.

Four experiments examined attentional flexibility in listening to polyrhythmic patterns. Musically trained and untrained listeners detected changes in timing of 1 tone (the lower tone) in a 3:2 polyrhythm in which high and low tones varied in frequency separation. Experiment 1 encouraged integrative attending; all listeners performed significantly poorer in conditions with wide as opposed to narrow frequency separations. Experiment 2, which encouraged selective attending to low tones, reversed these results: Performance was poorer in the narrow frequency conditions. In neither experiment did skill interact with frequency separation. Experiments 3 and 4 extended these findings to moderate frequency separations. Over all experiments, musically trained listeners exhibited an enhanced ability to detect timing variations, but not flexibility of perceptual organization as it applies to detection of timing changes. Instead, pattern structure (e.g., frequency and time relation) decisively influenced perception for both levels of skill.

Attention↗

Hesitations in manual tracking: a single-channel limit in response programming.

When subjects used a manual joystick to track the motion of a visual target (in either zero-order or first-order control), hesitations in tracking often occurred when the other hand responded to an auditory stimulus. These hesitations are related to postponement in the psychological refractory period effect. Because few hesitations occurred when the auditory stimulus was the no-go case of a go-no-go paradigm, hesitations must arise primarily during "late" processing associated with the concurrent response rather than during "early" perceptual or decision-making processes. Other findings suggest that the single-channel processing limit is in programming (as opposed to selecting or generating) concurrent responses. Blanking of the target also produced hesitations through a different mechanism.

Acoustic Stimulation↗

The relation of perception and motor action: ideomotor compatibility and interference in divided attention.

Ideomotor theory is one variation of the general position that perception and motor action are related. According to this theory, a perceptual representation of the goal of a response must be generated prior to response initiation. Ideomotor theory can be extended by assuming that generation of this representation, which usually is required prior to motor action, is not needed if the stimulus itself corresponds to the response goal, that is, if the stimulus and response are ideomotor compatible. Because processing to generate the response representation is not needed with ideomotor compatibility, it should be possible to control two responses simultaneously without mutual interference if at least one stimulus-response relation is ideomotor compatible. Although supported in previous work involving discrete responses, this prediction of perfect time-sharing was found not to hold in the experiments reported here. These experiments, unlike those showing perfect time-sharing, involved continuous responses. We propose an alternative version of ideomotor compatibility, in which perfect time-sharing can occur if an integrated stimulus is provided to match the continuous and integrated response.

Journal Article↗

Tests of parallel versus integrated structure in polyrhythmic tapping.

Musically trained subjects tapped three beats with their right hand versus two beats with their left hand in synchrony with two corresponding tones. For independent groups of subjects, the pitch difference of the two tones was either small to encourage an integrated perceptual organization or large to encourage a streamed perceptual organization. Integrated versus parallel motor organization was tested by examining the pattern of covariances among intertap intervals. All subjects exhibited integrated motor organization. An integrated multiplicative hierarchical model of motor organization was superior to a serial chained model and to an independent hierarchical model in describing the pattern of covariances. The subjects who heard tones that encouraged an integrated percept performed with less variability than the subjects who heard tones that encouraged a streamed percept. This superior performance with an integrated motor organization and an integrated rather than a streamed perceptual organization is interpreted as evidence for temporal perceptual-motor compatibility.

Journal Article↗

On marching to two different drummers: perceptual aspects of the difficulties.

People have remarkable difficulty generating two responses that must follow different temporal sequences, unless the temporal patterns are simply related (e.g., periods in 2:1, 3:1 relation). For example, it is hard to tap to two conflicting rhythms presented concurrently (i.e., a polyrhythm) using the right and left hands (Klapp, 1979), or to tap while articulating a conflicting speech utterance (Klapp, 1981). The present experiments indicate that difficulties in processing conflicting rhythms occur even when people must (a) merely monitor the stimuli and indicate the termination of one rhythmic sequence or (b) tap with a single hand. Responding to polyrhythms is thus difficult even without multiple limb coordination. Furthermore, the difficulty of two-handed tapping to polyrhythms that involve two different tones was found to decrease as the pitch difference between the tones was decreased. This result indicates that the difficulty of rhythmic coordination can be perceptually manipulated in a striking fashion. Polyrhythmic performance thus provides an excellent opportunity for examining possible interactions of perceptual and motor organizations.

Auditory Perception↗

Programming time as a function of response duration: a replication of "dit-dah" without possible guessing artifacts.

Reaction time was longer prior to longer-lasting pressing responses for low probability, unanticipated movements. By contrast, reaction time was independent of response duration for high probability, anticipated movements. This replicates and extends previous findings for choice and simple reaction time in the "dit-dah" paradigm. The present results (unanticipated responses) cannot be given a selective anticipation interpretation because the comparison is between responses which are never anticipated. The previous paradigm was open to an alternative interpretation in which selective anticipation of dit rather than dah could have produced the differences in choice reaction time. Confirmation of the finding that variations in required response duration lead to differences in reaction time supports the view that the underlying parameter of "complexity" in the "memory drum theory" may be response duration.

Journal Article↗

Technical considerations regarding the short (dit)-long (dah) key press paradigm.

The finding of longer reaction time prior to longer-lasting responses (e.g., Klapp, 1977a; Klapp, Wyatt. & Lingo, 1974) was not replicated by Kerr (1979) in a statistically powerful attempt. The present experiment confirms that this effect is not reliable when duration knowledge of results is similar to that used by Kerr, although a reliable long-short effect was obtained with other knowledge of results arrangements. This unexpected sensitivity to knowledge of results suggest that previous results from this paradigm must be interpreted with caution.

Journal Article↗

Motor programming is not the only process which can influence RT: some thoughts on the Marteniuk and MacKenzie analysis.

The current status of research on the memory drum theory is evaluated with emphasis on the issues raised by Marteniuk and MacKenzie (1981). A general theme emerging from this review is that response programming is not the only process which can influence RT and that distinguishing programming from non-programming effects clarifies rather than "clouds" the issues.

Comment↗

The memory drum theory after twenty years: comments on Henry's note.

The difference between the Henry "memory-drum" theory and our version is that ours includes, an additional assumption that, after programming has occurred, the resultant representation can be stored in short-term memory. Otherwise, the essential ideas are the same in the two theories. Implications of the presently available data for the distinction between the theories are discussed. Regardless of how one evaluates our added assumption, it is clear that the essential insight of the Henry theory has fared very well in the 20 years since the theory first appeared in print.

Comment↗

Programmed control of aimed movements revisited the role of target visibility and symmetry.

Reaction time prior to starting a 2-mm amplitude aimed movement was studied as a function to target size and experimental procedure. Consistent with a report by Klapp, choice reaction time increased as target size decreased when the visual signal that initiated the reaction time interval also indicated which of two targets was to be hit. This result implies response programming during the reaction time interval, with more programming time for slower movements to smaller targets. By contrast, in a simple reaction time procedure, there was no effect of target size on reaction time, suggesting that the response can be programmed in advance when the appropriate target is precued. This provided a control for speed-accuracy trade-off, supporting the programming interpretation of the choice reaction time result. In another condition in which both targets could be viewed while waiting for the auditory signal that initiated the reaction time interval and indicated which target to hit, choice reaction time was independent of target size provided that both possible targets on each trial were of the same size. The overall results suggest that response programs include both spatial and temporal information, and that parallel programming of different spatial goals is possible provided that the responses are of the same duration.

Acoustic Stimulation↗

The problem may be more difficult to solve than it appears: a reply to zelaznik.

Zelznik (1978) and I agree that his comment applies only to Experiment 1 of my series of three experiments, and I note that the weight of my argument was based on the other two experiments. Although agreeing with his analysis of the problem in Experiment 1, I note that the recommended solution may introduce a new problem in the course of eliminating the old one. It is fortunate that my conclusion can rest on converging operations and is not tied to the particular paradigm in question.

Journal Article↗

Response programming, as assessed by reaction time, does not establish commands for particular muscles.

In previous studies, response programming has been inferred from a relation between reaction time and the nature of the response which follows. However, it has not been clear whether this programming process generates commands for specific muscles or abstract timing networks which can be applied to any appropriate muscle group. Experiment 1 employed the Sternberg (1969) additive-factor method to show that muscle selection need not be completed before such programming begins, a conclusion which is inconsistent with the view that this process establishes commands to previously selected muscles. Experiments 2 and 3 provide converging evidence against the muscle-specific view of programming by showing that advance programming of response timing can occur when the response muscle is not specified. A theoretical framework encompassing these and previous results is proposed.

Journal Article↗

Relation between programming time and duration of the response being programmed.

When the nature of motor response is varied, holding the number of alternative responses constant, differences in choice reaction time can be attributed to differences in response programming time. The present experiments suggest that although changes in response duration are not necessary to produce small differences in programming time, such response duration changes may be a sufficient condition for the programming time to change and necessary condition for very large changes in programming time. Implications of this conclusion for theories of response programming are discussed.

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