Modeling the conscious correlates of recognition memory: Reflections on the remember-know paradigm

Understanding how memory processes contribute to the conscious experience of memory is central to contemporary cognitive psychology. Recently, many investigators (e.g., Gardiner, 1988) have examined theremember-know paradigm to understand the conscious correlates of recognition memory. A variety of studies have demonstrated that variables have different effects on remember and know responses, and these findings have been interpreted in the context of dual-process models of recognition memory. This paper presents a single-process model of the remember-know paradigm, emphasizing the dependence of remember and know judgments on a set of common underlying processes (e.g., criterion setting). We use this model to demonstrate how a single-process model can give rise to the functional dissociations presented in the remember-know literature. We close by detailing procedures for testing our model and describing how those tests may facilitate the development of dual-process models.     

The development of rulebound strategies for manipulating seriated cups: A parallel between action and grammar

Systematic observation of American children from 11 to 36 months of age playing with seriated nesting cups established the existence of a developmental sequence of rulebound or consistent strategies for combining the cups. The three action strategies seem formally homologous to certain grammatical constructions, and the manipulative strategies are acquired in the same developmental order as the corresponding grammatical structures. These strategies might therefore constitute a manifestation of some underlying structural capacities critical for language acquisition. The development of seriation described by Piaget for children from 4 to 8 years of age working with other materials was replicated in this much younger age range using nesting cups. These stages in the growth of a concept of ordinal quantity turn out to be empirically and theoretically related to the rulebound strategies upon which the study focused.     

Is implicit sequence learning impaired in schizophrenia? A meta-analysis

Cognition in schizophrenia seems to be characterized by impaired performance on most tests of explicit or declarative learning contrasting with relatively intact performance on most tests of implicit or procedural learning. At the same time there have been conflicting results for studies that have used the Serial Reaction Time (SRT) task to examine implicit learning in people with schizophrenia. In the present research, we used meta-analysis to clarify whether or not people with schizophrenia show impaired performance on the SRT task. A systematic review found nine studies published in peer review journals that had each compared the performance of a group of people with schizophrenia with healthy controls on the standard SRT task or a variant of it. The resulting meta-analysis represented the responses of 205 participants with schizophrenia and 159 healthy controls on the SRT task. The analysis found that participants with schizophrenia perform less well than controls reflected by a pooled effect size of 0.51. A secondary analysis of all nine studies found that they all reported a point estimate of the change in reaction time between sequence and random trials that was greater for the controls. We conclude that there is a moderate impairment in implicit sequence learning among people with schizophrenia and speculate on the implications of this for understanding this disorder. Suggestions for improving the methodological quality and statistical reporting of studies of this topic are made.     

Using ROC curves to test models of recognition memory: The relationship between presentation duration and slope

Many theories of memory predict that the slope of the z-transformed receiver-operating characteristic (ROC) curve should decrease with increases in the memory strength of old items. While several prior studies have failed to demonstrate this effect, the results of two experiments demonstrate that increasing presentation duration can reduce the slope of the z-transformed ROC curve. These results raise questions about the generality of prior results and of dual-process theories designed to accommodate those results. We close by emphasizing that determining the experimental circumstances that affect whether or not the slope of the z-transformed ROC curve decreases will provide important constraints on theories of recognition memory.     

Value-based choice: An integrative,neuroscience-informed model of health goals

Objective: Traditional models of health behaviour focus on the roles of cognitive, personality and social-cognitive constructs (e.g. executive function, grit, self-efficacy), and give less attention to the process by which these constructs interact in the moment that a health-relevant choice is made. Health psychology needs a process-focused account of how various factors are integrated to produce the decisions that determine health behaviour.

Design: I present an integrative value-based choice model of health behaviour, which characterises the mechanism by which a variety of factors come together to determine behaviour. This model imports knowledge from research on behavioural economics and neuroscience about how choices are made to the study of health behaviour, and uses that knowledge to generate novel predictions about how to change health behaviour. I describe anomalies in value-based choice that can be exploited for health promotion, and review neuroimaging evidence about the involvement of midline dopamine structures in tracking and integrating value-related information during choice. I highlight how this knowledge can bring insights to health psychology using illustrative case of healthy eating.

Conclusion: Value-based choice is a viable model for health behaviour and opens new avenues for mechanism-focused intervention.     

Ambient Green and Creativity

This research examined an important applied question: whether viewing ambient green (relative to red) on the wall of a workspace would facilitate creativity. A methodologically sound experiment revealed no influence of green on creativity. Care must be taken when interpreting a null result, but these data do not provide support for the presence of a relation between ambient green and creativity. This research also highlights the need for more research in the area of ambient color and psychological functioning, and the need for caution regarding the tendency to move to real-world recommendations before a firm empirical base is established.     

Episodic representations support early semantic learning: evidence from midazolam induced amnesia

Current controversy exists regarding the role of episodic representations in the formation of long-term semantic memories. Using the drug midazolam to induce temporary amnesia we tested participants' memories for newly learned facts in a semantic cue condition or an episodic and semantic cue condition. Following midazolam administration, memory performance was superior in the episodic and semantic condition, suggesting early semantic learning is supported by episodic representations.     

Midazolam amnesia and short-term/working memory processes

We examined whether midazolam impairs short-term/working memory processes. We hypothesize that prior dissociations in midazolam's effects on short-term/working memory tasks and episodic memory tasks arise because midazolam has a larger effect on episodic memory processes than on short-term/working memory processes. To examine these issues, .03 mg/kg of participant's bodyweight of midazolam was administered in a double-blind placebo-controlled within-participant design. Performance on the digit span and category generation/recall tasks was examined. The results of Experiment 1 demonstrated that: (1) midazolam impaired performance on the digit span task; (2) midazolam did not impair performance on the category generation task; (3) midazolam impaired performance on the category recall task; and (4) midazolam's effect on category recall was four times as large as its effect on digit span. The results of Experiment 2 demonstrated that midazolam did not impair digit span performance when the digit span task was administered at a later time. These results suggest that midazolam can impair short-term/working memory processes, but these effects are substantially smaller than midazolam's effect on episodic memory processes. Moreover, they demonstrate that conscious awareness of materials during study is not sufficient to produce episodic memory.