Dual-process theories of reasoning: The test of development

Dual-process theories have become increasingly influential in the psychology of reasoning. Though the distinction they introduced between intuitive and reflective thinking should have strong developmental implications, the developmental approach has rarely been used to refine or test these theories. In this article, I review several contemporary dual-process accounts of conditional reasoning that theorize the distinction between the two systems of reasoning as a contrast between heuristic and analytic processes, probabilistic and mental model reasoning, or emphasize the role of metacognitive processes in reflective reasoning. These theories are evaluated in the light of the main developmental findings. It is argued that a proper account of developmental phenomena requires the integration of the main strengths of these three approaches. I propose such an integrative theory of conditional understanding and argue that the modern dual-process framework could benefit from earlier contributions that made the same distinction between intuition and reflective thinking, such as Piaget’s theory.     

Attentional and structural constraints on visual encoding

We examined the mechanisms that mediate the transfer of information from visual input to storage in memory. Observers performed two concurrent tasks, one of which required input into memory. We discovered that the processes involved in the transfer of information from sensory input into memory cause slowing in concurrent cognitive tasks (dual-task slowing). We used the dual-task slowing effect to demonstrate that memory encoding requires more time when more information is to be encoded and to show that dual-task slowing occurs long after the initial perceptual encoding of visual information (Exp. 1). These results suggest a late and central locus of interaction between the two tasks. Experiment 2 also used two concurrent tasks. However, we reversed the direction of interaction between them and produced a memory deficit from the execution of a concurrent task. Together the results suggest that the mechanisms that encode information into memory belong to a family of mechanisms that are involved in dual-task slowing phenomena and that have been studied under the rubric of the PRP effect (psychological refractory period). We were able to locate the most probable locus of the dual-task interactions to a process that appears necessary for memory encoding. We call this process short-term consolidation. Received: 20 July 1997 / Accepted: 17 March 1998     

Highs and Lows in Motor Control Development

Abstract

Motor control is classically described as relying on two components: anticipatory control (feedforward processing) and online control (feedback processing). Here we aimed to unveil the developmental steps of both feedback and feedforward control in 5–10 years old children, using a simple and ecological task. We manipulated object’s weight in a reach-to-displace paradigm. When the weight was known before lifting it, anticipatory processes were quantifiable during the reaching phase. Conversely, an unknown weight triggered online corrections during the displacing phase. Movement kinematics revealed that children anticipate this objet property as young as 5 y-o. This anticipation becomes adequate around 7 y-o and is paralleled by poor online corrections. This simple yet relevant paradigm should allow quantifying deviations from neurotypical patterns in disorders of motor control.     

Effects of background music on phonological short-term memory

Immediate memory for visually presented verbal material is disrupted by concurrent speech, even when the speech is unattended and in a foreign language. Unattended noise does not produce a reliable decrement. These results have been interpreted in terms of a phonological short-term store that excludes non-speechlike sounds. The characteristics of this exclusion process were explored by studying the effects of music on the serial recall of sequences of nine digits presented visually. Experiment 1 compared the effects of unattended vocal or instrumental music with quiet and showed that both types of music disrupted STM performance, with vocal music being more disruptive than instrumental music. Experiment 2 attempted to replicate this result using more highly trained subjects. Vocal music caused significantly more disruption than instrumental music, which was not significantly worse than the silent control condition. Experiment 3 compared instrumental music with unattended speech and with noise modulated in amplitude, the degree of modulation being the same as in speech. The results showed that the noise condition did not differ from silence; both of these proved less disruptive than instrumental music, which was in turn less disruptive than the unattended speech condition. Theoretical interpretation of these results and their potential practical implications for the disruption of cognitive performance by background music are discussed.