On the use of a concurrent memory load to measure attention and automaticity.

Abstract

The concurrent-memory-load technique identifies attention demands with interactions between reaction-time-task parameters and the size of the load on memory. Three experiments are reported in which a multiple-choice, reaction time task involving two, four, and eig-ht stimulus-response (S-R) alternatives was performed alone and in the retention interval of a short-termmemory task involving ordered recall of eight digits. In Experiment 1, assignment of stimulus letters to response buttons (S-R mapping) was consistent for 6 days but varied on the seventh. Memory load and number of alternatives interacted early in practice, but the interaction diminished over days, and the effects were additive on Day 6. When the S-R mapping changed on Day 7, the interaction returned. In Experiment 2, S-R mapping varied daily for 6 days, and the interaction remained stable throughout practice. In Experiment 3, S-R mapping was consistent for 6 days and varied on the seventh, but the memory task was not introduced until Days 6 and 7. The interaction between memory load and number of alternatives was stronger on Day 7, after the mapping had changed, than it was on Day 6, after practice with consistent mapping. The discussion focuses on the validity of the concurrent-memory-load technique and its relation to another method for measuring attention and automaticity, and on the importance of practice with consistent mapping and practice with dual-task conditions in the development of automaticity.In general terms, attention refers to a cen-performance in some task environment. Pertral process that coordinates and controls formance is considered automatic to the extent that it is coordinated without attentional This research was supported by Grant AO 682and the development of automaticity from the National Research Council of Canada. I with practice refers to a transfer of control would like to thank Lee Smith for running the sub-from attention to reliable characteristics of jects. I am grateful to Ron Fisher, Paul Kolers, the task environment. The concurrent-memMorris Moscovitch, Ben Murdock Sandor Wise-or load technique has been offered as a man, and Jane Zbrodoff for their thoughtful comi • /• • ± *.-j^. ments and criticism throughout the development of method for measuring attention and automathis manuscript, and to Tom Carr, Michael Posner, ticity, and the experiments reported here and Anne Treisman for thorough reviews of an were designed to evaluate it. earlier version.The technique assumes that the capacity Requests for reprints should be sent to Gordon r .. 1 * • <• •,. i ,1 , • D. Logan, Department of Psychology, Erindale for attentional control is limited, that in pnnCollege, University of Toronto, Mississauga, On-ciple attentional capacity can be shared by all tario, Canada LSL 1C6.tasks and task components, and that atten-

On the ability to inhibit thought and action: General and special theories of an act of control.

“…Our finding that the stop process does not share capacity with the go process is remarkable because many processes share capacity (Pashler, 1994), especially control processes (Logan, 1978(Logan, , 1979Shiffrin & Schneider, 1977). It is worth speculating on reasons why the stop process may escape the limitations that apply to other processes.…”

“…The sum of the rates decreased from two choices ( 2go ϩ ε 2go ϭ 0.252) to four choices ( 4go ϩ 3ε 4go ϭ 0.205) to six choices ( 6go ϩ 5ε 6go ϭ 0.153), indicating stronger capacity limitations than a fixed-capacity model would predict (see Equation 18). One interpretation of this hyperlimited capacity is that it takes capacity to share capacity: Preparing and coordinating several response alternatives consume capacity that could be used for processing information (e.g., Logan, 1978Logan, , 1979Pashler, 1994). Whatever the interpretation, the model fits suggest the go process is limited in capacity, and that allows us to ask whether the stop process shares the same capacity.…”

“…However, the evidence for hierarchical control is controversial despite the widespread appeal of the idea (see Cooper & Shallice, 2000, 2006, vs. Botvinick & Plaut, 2004, 2006, and it is not clear that higher level processes rely on different capacities than lower level ones (see Logan, 1979). More research is required to evaluate this possibility.…”

Automaticity: A Theoretical and Conceptual Analysis.

“…The degree of capacity consumption is often operationalized as dual-task interference (e.g., Baddeley, 1986;Logan, 1978Logan, , 1979; but see Shiffrin & Schneider, 1977). In dual-task studies, participants perform a primary task simultaneously with a secondary task that is assumed to consume resources.…”

Working Memory, Task Switching, and Executive Control in the Task Span Procedure.

“…They differ primarily in the assumptions they invoke to explain the limit. Some theories assume that a limited capacity for activation constrains the number of items that can be kept sufficiently active to be recalled (Anderson, Reder, & Lebiere, 1996;Daneman & Carpenter, 1980;Just & Carpenter, 1992;Logan, 1978Logan, , 1979see Kahneman, 1973;Moray, 1967;Posner & Boies, 1971). Other theories assume that activation decays over time and only a limited number of items can be kept active enough to be recalled Baddeley, 1986Baddeley, , 1996Baddeley & Hitch, 1974;Cowan, 1995Cowan, , 1999Hitch, Towse, & Hutton, 2001).…”