Alzheimer's disease (AD) is a progressive neurodegenerative disease marked by deficits in episodic memory, working memory (WM), and executive function. Examples of executive dysfunction in AD include poor selective and divided attention, failed inhibition of interfering stimuli, and poor manipulation skills. Although episodic deficits during disease progression have been widely studied and are the benchmark of a probable AD diagnosis, more recent research has investigated WM and executive function decline during mild cognitive impairment (MCI), also referred to as the preclinical stage of AD. MCI is a critical period during which cognitive restructuring and neuroplasticity such as compensation still occur; therefore, cognitive therapies could have a beneficial effect on decreasing the likelihood of AD progression during MCI. Monitoring performance on working memory and executive function tasks to track cognitive function may signal progression from normal cognition to MCI to AD. The present review tracks WM decline through normal aging, MCI, and AD to highlight the behavioral and neurological differences that distinguish these three stages in an effort to guide future research on MCI diagnosis, cognitive therapy, and AD prevention.

Several researchers have reported that instructing participants to imagine items using the Deese-Roediger-McDermott (DRM) paradigm lowers false memory rates (Foley, Wozniak, & Gillum, 2006). However, other researchers have found that imagery does not always lower false memory rates (Robin, 2010), and investigators have examined the effects of imagery manipulation on semantic but not phonological lists. In the present study, we presented 102 participants with semantic and phonological DRM lists, followed by a free recall test and final recognition test. Some participants received instructions to imagine list items during the study phase to facilitate memory, and others were simply told to remember list items. Imagery instructions enhanced correct memories and further suggested a trend for decreased false memories. A test type by list type interaction also emerged, with phonological lists eliciting higher false memories at recall, and semantic lists eliciting higher false memories at recognition. Directions for future research are discussed.

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Imagining a fictitious childhood event can lead to a false belief in that event’s occurrence, an effect called imagination inflation. However, the nature of imagery induction can vary considerably and such differences have not been systematically addressed in the literature. In the current study, participants provided confidence ratings for a series of events before and after imagery exercises. We manipulated imagery instructions (guided vs. prompted, a between-subjects factor) as well as event valence (positive vs. negative, a within-subjects factor). Results revealed inflation effects only under guided imagery instructions with negative events being the most susceptible to inflation. Interestingly, a portion of our sample (24%) experienced decreases in confidence following imagery or imagination deflation. Content analyses of imagery reports provided a more thorough understanding of inflation and deflation effects within a source monitoring framework.

In 2 experiments, the effect of collaborative encoding on memory was examined by testing 2 interactive components of co-construction processes. One component focused on the nature of the interactive exchange between collaborators: As the partners worked together to create descriptions about ways to interact with familiar objects, constraints were imposed on the interactions by requiring them to take turns (Experiment 1) or to interact without constraints (Experiment 2). The nature of the relationship between partners was manipulated as well by including 2 pair types, friends or unfamiliar peers (Experiments 1 and 2). Interactive component effects were found to influence spontaneous activations through content analyses of participants’ descriptions, the patterns of false recognition errors, and the relationship between content and errors. The findings highlight the value of examining the content of participants’ collaborative efforts when assessing the effects of collaborative encoding on memory and point to mechanisms mediating collaboration’s effects. Because the interactions occurred within the context of an imagery generation task, the findings are also intriguing because of their implications for the use of guided imagery techniques that incorporate co-construction processes.