A cognitive framework for explaining serial processing and sequence execution strategies

Abstract

Behavioral research has produced many taskspecific cognitive models that do not say much about the underlying information-processing architecture. Such an architecture is badly needed to better understand how cognitive neuroscience can benefit from existing cognitive models. This problem is especially pertinent in the domain of sequential behavior where behavioral research suggests a diversity of cognitive processes, processing modes and representations. Inspired by decades of reaction time (RT) research with the Additive Factors Method, the Psychological Refractory Period paradigm, and the Discrete Sequence Production task, we propose the Cognitive framework for Sequential Motor Behavior (C-SMB). We argue that C-SMB accounts for cognitive models developed for a range of sequential motor tasks (like those proposed by Keele et al., Psychological Review, 110(2), 316-339, 2003; Rosenbaum et al., Journal of Experimental Psychology: Human Perception and Performance, 9(1), 86-102, 1983, Journal of Memory and Language, 25, 710-725, 1986, Psychological Review, 102, 28-67, 1995 Schmidt, Psychological Review, 82(4), 225-260, 1975;Sternberg et al., 1978, Phonetica, 45, 177-197, 1988. C-SMB postulates that sequence execution can be controlled by a central processor using central-symbolic representations, and also by a motor processor using sequencespecific motor representations. On the basis of this framework, we present a classification of the sequence execution strategies that helps researchers to better understand the cognitive and neural underpinnings of serial movement behavior.

Differences in chunking behavior between young and older adults diminish with extended practice

“…Explicit sequence knowledge was correlated with the IED for older adults in keeping with previous findings (Verwey, 2010), suggesting that when older adults are executing keying sequences this may not solely rely on pure motor representations. This is in line with the recently proposed cognitive framework for sequential motor behavior (C-SMB, Verwey et al, 2015), built on the foundations of the DPM, which postulates that the representations underlying motor skill and motor chunks may be mixed. That is, verbal and/or visuospatial central-symbolic representations may underlie skilled sequence performance too.…”

Skill in discrete keying sequences is execution rate specific

“…Execution rate of such familiar sequences appears to decrease only little when element-specific stimuli are no longer displayed, while in contrast, execution rate decreases substantially if only a single element is being altered (Abrahamse et al, 2013;Verwey, 1999Verwey, , 2010. There is general consensus now that skilled motor behavior is based on a practice-, task-, and age-dependent mixture of various sequence representations (Panzer, Gruetzmacher, Ellenbuerger, & Shea, 2014;Shea et al, 2016;Verwey, Shea, & Wright, 2015;Wiestler, Waters-Metenier, & Diedrichsen, 2014). These ideas have recently been worked out in the cognitive framework for Sequential Motor Behavior (C-SMB; Verwey et al, 2015) which distinguishes between motor chunks, spatial, and verbal central-symbolic sequence representations, and associative sequence representations.…”

“…These verbal and spatial representations are said to underlie the so-called central-symbolic execution mode . The responsible central-symbolic representations develop more rapidly than motor chunks, but they are associated with lower execution rates than motor chunks because it takes substantial processing to extract the individual movements from these abstract representations (Hikosaka et al, 1999;Verwey et al, 2015). The more abstract a sequence representation the slower execution of the motor sequence that it controls.…”

Hemispheric asymmetries and the control of motor sequences

“…Indicative of a motor chunk is a relatively slow initiation (i.e., first key press) followed by faster subsequent responses. There was no evidence of multiple motor chunks, i.e., key presses with a long response time after the first one, which would point to additional preparation processes [54].…”