Processing demands of sequential information

Abstract

Three experiments examined the processing capacity required to use sequential information in a serial reaction time task with partially predictable sequences. The first two experiments varied the response stimulus interval (RSI) between o and 500 msec and found the relative advantage of the high-probability stimulus to be independent of the length of the RSI. The third experiment compared utilization of sequential information either with or without a secondary task. The secondary task did not affect the high-probability stimulus but did increase the amount of time required to respond to the low-probability events. The results are discussed in terms of the attentional demands of memory access.In most skilled tasks, events occurring at one point in time can be used to predict what is likely to occur later. When this information is used, performance is facilitated. Hershman and Hillix (1965) and Shaffer and Hardwick (1968), for example, showed that people type words, which are highly redundant, faster than random letters, even when only one letter of a word is exposed at a time. One letter in a word helps people predict what letter will occur next, reducing typing time if the anticipated letter does occur. More formally, Hyman (1953), Hyman and Umilta (1969), and Umilta and Trombini (1968) found that the time to process and respond to successive events depends on the information content of the events. When information is reduced by making some events more likely to occur following other events, reaction time (RT) decreases.The present study asks if processing capacity is required to use this type of sequential information. In the first two experiments, the time available for using sequential information is controlled by manipulating the time between the response to one stimulus and the onset of the next stimulus in a partially the next. In a third experiment, the time for processing sequential information is reduced not only by a short interval between the response and stimulus, but also by adding a secondary task to further compete for processing capacity.These experiments have general implications for theories of attention. Posner and Keele (1970) and Keele (1973) suggest that attention can be assessed by the degree of interference between tasks. Processes that do not interfere with other processes are said to require no attention. Thus, the overlap between anticipating a subsequent stimulus and processing the current stimulus will ten us whether or not anticipation requires attention. Posner and Boies (1971) used the interference technique to infer that nonspecific preparation generated by a warning signal is nonattentive. Here we ask whether or not anticipation of a specific event, which requires access to memory in order to determine what event is likely to occur next, requires attention. More generally, therefore, the present studies relate to the question of whether or not access to information stored in memory is an attention-demanding process. EXPERIMENT IThe basic task was a serial RT task with four li...

Visual working memory load does not eliminate visuomotor repetition effects

“…Finally, we should note that in Experiment 1 we found that memory load, regardless of its type, increased the size of the color-response repetition benefit. A similar effect was reported by Keele and Boies (1973) in the context of a task requiring participants to quickly report sequences of target locations while remembering five consonants. However, in Experiment 2, this effect disappeared.…”

Control of stimulus-response translation in dual-task performance

“…Although memory load typically has a strong effect on performance in both the primary task and the memory task itself, it does not interact with a whole number of manipulations of perceptual factors (e.g., stimulus brightness or quality), attentional factors (e.g., array size or cuing), and decisional or response-related factors (e.g., yes-no decision or S-R compatibility) (for an overview, see Logan, 1980). Interestingly, however, memory load does interact with some factors that are likely related to S-R translation, such as response-set size (Logan, 1979), S-R mapping-rule complexity (Logan, 1980), or stimulus predictability (Keele & Boies, 1973). This suggests that, as Logan (1980) has pointed out, the digit-memory task uses up capacity from the same system or medium that prepares and holds S-R mapping rules, possibly by interfering with rehearsing the rules before the trial (Pashler, 1994).…”

Automatic aftereffects in two-choice reaction time: A mathematical representation of some concepts.

“…Experimental support for the notion of decay has been found by several researchers who observed decreasing repetition effects with an increasing RSI (Bertelson, 1961;Bertelson & Renkin, 1966;Hale, 1967;Smith, 1968;Umilta et al, 1972). There are, however, other researchers who found little or no effect of a changing RSI on the repetition effect (Keele, 1969;Keele & Boies, 1973;Schvaneveldt & Chase, 1969). These seemingly conflicting results can be ascribed to other variables such as stimulus-response compatibility, practice, and number of alternatives, whose influences are often compounded with RSI influences.…”

“…The actual RSI of Kirby would then probably exceed 200 ms, which explains the finding of an expectancy effect. The same confusing methodology was also used by other researchers (e.g., Bertelson & Renkin, 1966), and sometimes the actual RSI was additionally prolonged with the warming-up time of the presented stimuli when incandescent lamps were used (Keele & Boies, 1973). Apart from methodological differences, the influence of RSI has often been compounded with the influence of other variables, such as stimulusresponse compatibility, practice, and number of alternatives.…”