Malcolm D. MacLeod

Gone but Not Forgotten: The Transient Nature of Retrieval-Induced Forgetting

Recent research has demonstrated that the act of remembering can prompt temporary forgetting or, more specifically, the inhibition of particular items in memory. Extending work of this kind, the present research investigated some possible boundary conditions of retrieval-induced forgetting. As expected, a critical determinant of temporary forgetting was the interval between guided retrieval practice and a final recall test. When these two phases were separated by 24 hr, retrieval-induced forgetting failed to emerge. When they occurred in the same testing session, however, retrieval practice prompted the inhibition of related items in memory (i.e., Experiment 1). A delay of 24 hr between the encoding of material and guided retrieval practice reduced but did not eliminate retrieval-induced forgetting (i.e., Experiment 2). These findings are considered in the wider context of adaptive forgetting.

On recollections lost : When practice makes imperfect

Recent research has demonstrated that the act of remembering can prompt forgetting or, more specifically, the inhibition of specific items in memory (M. C. Anderson & B. A. Spellman, 1995). This line of inquiry was extended through an investigation of the process and consequences of retrieval-induced forgetting in social cognition. Across 3 studies, the findings clarify several unresolved issues in the psychology of forgetting. First, it was demonstrated that retrieval-induced forgetting extends to issues in social cognition (Experiment 1). Second, forgetting can be elicited even in task contexts in which perceivers are highly motivated to remember the presented material (Experiment 2). Third, forgetting is not moderated by the amount of retrieval practice that perceivers experience (Experiment 3). These findings are considered in the context of recent treatments of cognitive inhibition and goal-directed forgetting.

New evidence on the suggestibility of memory : the role of retrieval-induced forgetting in misinformation effects

Extending recent work that has demonstrated that the act of remembering can result in the inhibition of related items in memory, the present research examined whether retrieval-induced forgetting could provide a mechanism for explaining misinformation effects. Specifically, the authors found in their first study that the inhibition of critical items rendered the recollection of postevent information more likely in a subsequent test of memory. The authors established in their second study that when guided retrieval practice and final recall tests were separated by 24 hr, retrieval-induced forgetting failed to emerge and misinformation effects were absent. In contrast, a delay of 24 hr between initial encoding and guided retrieval practice produced not only retrieval-induced forgetting but also misinformation effects.

Can inhibition resolve retrieval competition through the control of spreading activation

Two experiments are reported in which the mechanisms underlying retrieval-induced forgetting for complex prose materials were investigated, using the independent probe technique pioneered by Anderson and Spellman (1995). These experiments provide additional empirical evidence in support of an inhibitory account of memory. Specifically, evidence emerged not only for the inhibition of nonpracticed items from practiced sets (i.e., first-order effects), but also for the inhibition of items from nonpracticed sets that were semantically related to practiced items in practiced sets (i.e., crosscategory effects) and for items from nonpracticed sets that were semantically related to nonpracticed items in practiced sets (i.e., second-order effects). These findings are considered in terms of Anderson and Spellman’s model of inhibitory processing. We also outline an alternative inhibitory interpretation. Specifically, we consider how inhibition may function as a way of controlling the spread of activation and what implications this may have for the flexibility and adaptiveness of memory.

The role of inhibitory control in the production of misinformation effects.

Recent research has indicated a link between retrieval-induced forgetting and the production of misinformation effects (J. Saunders & M. D. MacLeod, 2002). The mechanism underlying this relationship, however, remains unclear. In an attempt to clarify this issue, the authors presented 150 participants with misinformation under conditions designed to promote the activation of inhibitory control during the retrieval of information about a target event. A modified retrieval practice paradigm that used the independent probe method pioneered by M. C. Anderson and B. A. Spellman (1995) revealed that misinformation effects emerged only where misinformation had been introduced about items that had been subject to 1st-order, 2nd-order, or cross-category inhibition. By contrast, misinformation effects failed to emerge where inhibitory processing had not been activated. These findings are discussed in terms of inhibitory control, memory malleability, and their implications for the interviewing of eyewitnesses.

The Reality and Myth of Rape: Implications for theCriminal Justice System

This article sets out to evaluate the researchevidence for rape myths and the extent to which theyare causally related to rape proclivity; negativeattitudes towards rape victims; and the reporting ofsexual assault incidents to the police. In reviewingthis literature, we provide an evaluation of theimpact of this research on the criminal justice systemand possible future developments. We argue that thisresearch, while failing to provide conclusive evidenceof a causal relationship, has nevertheless played animportant part in shaping more sympathetic approachestowards rape victims in the criminal justice system.However, we also argue that the current research fallsshort of the level of proof required for it to beadmitted as evidence in criminal trials. We considera number of alternative uses including AmicusCuriae briefs, and the training of juries and judgesprior to hearing rape cases.

It's all in the detail: intentional forgetting of autobiographical memories using the autobiographical think/no-think task.

Using a novel autobiographical think/no-think procedure (ATNT; a modified version of the think/no-think task), 2 studies explored the extent to which we possess executive control over autobiographical memory. In Study 1, 30 never-depressed participants generated 12 positive and 12 negative autobiographical memories. Memories associated with cue-personal word pairings were learned to criterion. Participants were then asked to recall the memory associated with some of the cue-personal word pairs (i.e., think condition) or to avoid saying or thinking about the memory associated with others (i.e., no-think condition). In a subsequent test of recall, systematic forgetting effects emerged for no-think autobiographical memories compared to baseline that received neither no-think nor think instructions. These findings were extended and replicated in a second ATNT study (using a further 30 never-depressed participants), which showed that the forgetting of autobiographical memories in the no-think condition was unlikely to be a function of thought substitution or demand characteristics.

Retrieval Inhibition and Memory Distortion Negative Consequences of an Adaptive Process

Despite the fact that misinformation effects have long been studied by both applied researchers and modelers of human memory, there is little consensus as to the value of such endeavors. We argue that this may be due to a failure to identify the underlying mechanism responsible for such memory distortions. We consider novel evidence for a relationship between retrieval-induced forgetting and the reporting of misinformation. We also explore the extent to which retrieval inhibition underpins this relationship and the implications this has for the modeling of memory and finding potential solutions to real-world problems.

A Single Instruction Multiple Data Particle Filter

Particle filters are often claimed to be readily parallelisable. However, the resampling step is non-trivial to implement in a fine-grained parallel architecture. While approaches have been proposed that modify the particle filter to be amenable to such implementation, this papers novelty lies in its description of a Single Instruction Multiple Data (SIMD) implementation of a particle filter that uses N processors to process N particles. The resulting algorithm has a time complexity of O((log N)2) when performing resampling using N processors. The algorithm has been implemented using C for Graphics (CG), a language that enables the heavily pipelined architecture of modern graphics cards to be used to imitate a SIMD processor. Initial results are presented.

Retrieval Inhibition and Memory Distortion

Despite the fact that misinformation effects have long been studied by both applied researchers and modelers of human memory, there is little consensus as to the value of such endeavors. We argue that this may be due to a failure to identify the underlying mechanism responsible for such memory distortions. We consider novel evidence for a relationship between retrieval-induced forgetting and the reporting of misinformation. We also explore the extent to which retrieval inhibition underpins this relationship and the implications this has for the modeling of memory and finding potential solutions to real-world problems.