Know versus Familiar: Differentiating states of awareness in others' subjective reports of recognition

In the Remember-Know paradigm whether a Know response is defined as a high-confidence state of certainty or a low-confidence state based on familiarity varies across researchers and can influence participants' responses. The current experiment was designed to explore differences between the states of Know and Familiar. Participants studied others' justification statements to "Know" recognition decisions and separated them into two types. Crucially, participants were not provided definitions of Know and Familiar on which to sort the items--their judgements were based solely on the phenomenology described in the justifications. Participants' sorting decisions were shown to reliably map onto expert classification of Know and Familiar. Post-task questionnaire responses demonstrated that both the level of memory detail and confidence expressed in the justifications were central to how participants categorised the items. In sum, given no instructions to do so, participants classify Familiar and Know according to two dimensions: confidence and amount of information retrieved

Fractionating controlled memory processes and recall of context in recognition memory: a case report.

Recollection has been described as both a recognition memory judgment requiring cognitive control and the ability to retrieve contextual information about a prior occurrence. At the core of this article is the question whether or not these two subcomponents of recollection are dissociable in amnesia. In three experiments, we explored the influence of exclusion task instructions on performance in a single case (CJ), with the view to understand the relative contributions of control and source memory to recognition memory decisions. First, contrasting findings were obtained between tasks requiring strategic control or source reports. Second, even though CJ displayed some residual source memory relative to the ability to strategically control this information, his source memory capacity was time-limited. Our findings resonate with the novel proposal that recollection draws heavily upon working memory resources, and provide an example of how amnesic patients might utilize residual working memory capacity to solve episodic memory tasks

Switch costs in the self-memory system

Two studies on undergraduates examined the idea that the working self operates as an executive structure to constrain and co-ordinate the generation of autobiographical memories. A switching task was used, in which participants completed an autobiographical memory fluency task, either using alternating self-image cues, or the same cue repeatedly. In two experiments, there was a clear switch cost, whereby participants took longer to generate autobiographical memories when alternating between two different self-images. In the second experiment, there was also a similar cost associated with generating names and places from two separate domains, home and university. Taken together, these experiments support the idea that autobiographical memories and personal semantics are organized into a hierarchical structure, which can be probed using executive function-like tasks. In particular, the task switch cost points to retrieval systems being geared up to retrieving memories according to the current goals of the self. In terms of autobiographical retrieval, the self can thus be thought of as a mental structure which is subject to dynamic patterns of excitation and interference

Experiences of aiding autobiographical memory using the sensecam

Human memory is a dynamic system that makes accessible certain memories of events based on a hierarchy of information, arguably driven by personal significance. Not all events are remembered, but those that are tend to be more psychologically relevant. In contrast, lifelogging is the process of automatically recording aspects of one's life in digital form without loss of information. In this article we share our experiences in designing computer-based solutions to assist people review their visual lifelogs and address this contrast. The technical basis for our work is automatically segmenting visual lifelogs into events, allowing event similarity and event importance to be computed, ideas that are motivated by cognitive science considerations of how human memory works and can be assisted. Our work has been based on visual lifelogs gathered by dozens of people, some of them with collections spanning multiple years. In this review article we summarize a series of studies that have led to the development of a browser that is based on human memory systems and discuss the inherent tension in storing large amounts of data but making the most relevant material the most accessible

Retained ability to extract gist in childhood-acquired amnesia: Insights from a single case.

This paper presents the performance of a young amnesic person (CJ) in the DRM task. CJ was found to be sensitive to the DRM manipulation at a level comparable to controls in recognition and at a level higher than controls in free recall. Detailed analyses of recall intrusions lent further support to the finding that CJ is able to extract gist on the basis of semantic associations. Results are discussed with reference to relevant theory as well as the potential role of an impaired and immature cognitive system in adopting a semantic gist strategy in the absence of episodic memory

Detecting Subtle Changes in Visuospatial Executive Function and Learning in the Amnestic Variant of Mild Cognitive Impairment

BACKGROUND AND PURPOSE: Amnestic mild cognitive impairment (aMCI) is a putative prodromal stage of Alzheimer's disease (AD) characterized by deficits in episodic verbal memory. Our goal in the present study was to determine whether executive dysfunction may also be detectable in individuals diagnosed with aMCI. METHODS: This study used a hidden maze learning test to characterize component processes of visuospatial executive function and learning in a sample of 62 individuals with aMCI compared with 94 healthy controls. RESULTS: Relative to controls, individuals with aMCI made more exploratory/learning errors (Cohen's d = .41). Comparison of learning curves revealed that the slope between the first two of five learning trials was four times as steep for controls than for individuals with aMCI (Cohen's d = .64). Individuals with aMCI also made a significantly greater number of rule-break/error monitoring errors across learning trials (Cohen's d = .21). CONCLUSIONS: These results suggest that performance on a task of complex visuospatial executive function is compromised in individuals with aMCI, and likely explained by reductions in initial strategy formulation during early visual learning and "on-line" maintenance of task rules