Stuart T. Klapp

Automatizing alphabet arithmetic: I. Is extended practice necessary to produce automaticity?

Four experiments tested the necessity of extended practice in producing automaticity in an alphabet-arithmetic task in which subjects verified equations of the form A + 2 = C, asking whether C was two letters down the alphabet from A. Experiment 1 trained subjects on 40 alphabet-arithmetic facts for 12 sessions, demonstrating that extended practice was sufficient to produce automaticity. Experiment 2 produced the same degree of automaticity in a single session by having subjects rote memorize 6 facts, suggesting that extended practice is not necessary. Experiments 3 and 4 explored procedural differences between Experiments 1 and 2 to determine what was responsible for the large difference in the time required to develop automaticity. Experiment 3 compared learning rates with different numbers of facts (6, 12. and 18), and found learning rate to depend on the number of presentations of individual items, not on the number of items to be learned. Experiment 4 compared learning by performing the task (as in Experiment 1) with learning by remembering the facts (as in Experiment 2) and found no important differences between them. The results of all 4 experiments cannot be predicted by approaches that define automaticity in terms of resources or by listing properties, although they are readily predictable from theories that assume memory retrieval is the process that underlies automaticity. Is extended practice necessary to produce automaticity? Can automaticity to be produced without it? Extended practice is certainly sufficient. Many of the properties of automaticity can be produced by extended practice (e.g., Logan, 1978; Shiffrin & Schneider, 1977) or by using materials such as familiar words that have a history of extended practice outside the laboratory (e.g., Neely, 1977). However, sufficiency does not imply necessity. Existing data provide no answer. Common theoretical approaches to automaticity provide no answer either. Approaches that define atuomaticity in terms of manifest properties, such as speed, effortlessness, and autonomy (property-list approaches), are stipulative or descriptive but not predictive (e.g., Hasher & Zacks, 1979; LaBerge & Samuels, 1974; Shiffrin & Schneider, 1977). They provide no underlying mechanism from which predictions about the properties of automaticity or necessity of extended practice can be deduced.

Doing two things at once: The role of temporal compatibility

Performance in a periodically repeating keypress response was measured as a function of the relation between the response patterns required of the two hands. Compared to identical left- and right-hand responses, performance was degraded when the temporal periods of the left- and right-hand responses were not harmonically related. By contrast, performance was not degraded compared to the identical task control when the left- and right-hand responses had the same or harmonically related periods. These findings suggest a limitation in parallel generation of multiple time frames that is assumed to be associated with a late stage of central processing in which response commands are generated.

The negative compatibility effect: unconscious inhibition influences reaction time and response selection.

In the negative compatibility effect (NCE) a masked prime arrow, pointing left or right, is followed by an unmasked (visible) target arrow. The task is to press the left or right switch corresponding to the visible arrow. Surprisingly, reaction time is longer (slowed) when the prime and target indicate the same, rather than different, responses. By contrast, the effect of an unmasked prime is positive-opposite to the NCE. This indicates that the NCE is not attributable to incomplete masking; to the extent that the prime is visible, the NCE would be reduced by this positive influence. Thus, the NCE appears to result from unconscious processing of the prime and, in that sense, may be a form of subliminal perception. Additional findings show that the NCE is due to inhibition of a response code, that it is automatic in that it occurs even if the information in the prime and target could be ignored, and that it also influences response selection.

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.

Reaction Time Analysis of Two Types of Motor Preparation for Speech Articulation: Action as a Sequence of Chunks

Abstract Reaction time (RT) prior to speech articulation increased as a function of response complexity. The RT findings formed 2 patterns, each of which was a different Response Complexity × Paradigm (choice RT vs. simple RT) interaction. That result extends previous findings from manual button-pressing tasks (S. T. Klapp, 1995) to a different action modality. Two different types of response programming, INT and SEQ, are assumed in the interpretation. Whereas INT can be identified with response programming within a word, SEQ fits a different interpretation related to timing of onsets of speech units. A critical assumption is that a long response is represented as a sequence of chunks; that organization is subject to manipulation. New findings suggest some modifications of the previous theory.

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.

Motor programming within a sequence of responses.

Choice reaction time prior to a motor response has been shown to depend on the nature of the response to be made. This effect is assumed to represent variations in programming time. However, as the length of a response sequence increases this effect becomes smaller, suggesting that some response programming is postponed until after the response sequence is initiated. The present experiment studied this assumed programming within a sequence of responses. For sequences comprised of two Morse Code responses (e.g. dit-dah) the initial reaction time was independent of the terminal response. However, programming of this terminal response was apparent as a lengthening of the duration of intervals within the response when the terminal response was dah rather than dit. When programming of parts of the sequence is postponed beyond the reaction time interval, the programming occurs later and influences the timing of the sequence of responses.

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.

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.

Anatomic and environmental dimensions of stimulus-response compatibility: implication for theories of memory coding

Abstract Reaction time was higher when the relation between stimulus location and anatomic hand was reversed ( e.g. , left light-right hand) rather than direct ( e.g. , left light-left hand), even though the environmental location of the hand (up or down) was unrelated to the location of the stimulus (left or right). This effect was shown to be due primarily to decision processes, rather than to interhemisphere transfer delay. This result does not support the view that long-term memory for responses encodes environmental but not anatomic dimensions.