Working memory capacity is related to variations in the magnitude of an electrophysiological marker of recollection

Abstract

The links between the resources available for cognitive control and the ability to recover and maintain episodic content were investigated by contrasting an ERP index of recollection (the left-parietal ERP old/new effect) with a measure of working memory capacity (WMC). Participants were given the O-Span measure of WMC and completed a retrieval task in which they had to make responses on one key to previously studied words (targets) and responses on a second key to words that were presented at retrieval on either one or two occasions (new words and non-targets, respectively). The size of the ERP index of recollection associated with correct responses to targets was correlated with WMC, a finding consistent with the view that this ERP effect is linked to operations associated with maintaining information on-line in service of task goals. In addition, the degree to which left-parietal ERP old/new effects for targets were larger than for non-targets increased as WMC increased. Larger left-parietal ERP old/new effects for targets than for non-targets have been interpreted as evidence of successful prioritisation of recollection of target information. The link with WMC reported here is consistent this view, in so far as WMC indexes the availability of resources that are necessary to exert cognitive control over memory retrieval.

Event-related potential (ERP) evidence for source-monitoring based on the absence of information

“…One early suggestion was that this strategy would be adopted when target information was easy to retrieve and diagnostic by itself (Herron and Rugg, 2003b); however, Rosburg et al recently suggested that strategic retrieval depends more on the ease of non-target retrieval. Other studies have demonstrated that the similarity of sources is not, by itself, a trigger for using strategic retrieval (e.g., Evans et al, 2010;Wilding et al, 2005) and have shown a correlation between working memory capacity and the ability to engage in strategic recollection (Elward and Wilding, 2010). The results from the present study indicate that strategic recollection also occurs during source monitoring tasks.…”

“…As a result, the parietal ERP differences observed during source monitoring (RM or ISM) are not due to the mere inclusion of self-relevant information in the memory trace (e.g., cognitive operations) because parietal ERP differences persisted in these ISM studies in which all sources (i.e., actions) contained self-relevant characteristics. Instead, these results raise the possibility that internal sources prompt strategic recollection, as indicated by parietal effect differences (e.g., Bergström et al, 2009aBergström et al, , 2009bBergström et al, , 2007Elward and Wilding, 2010;Evans et al, 2010), when it simplifies or otherwise aids the judgment.…”

“…Parietal ERP differences have been observed between targets and non-targets and are often interpreted as evidence that recollection can be controlled (e.g., Herron andRugg, 2003a, 2003b). The basic idea is that, in some situations, people can identify targets by recollecting specific target-related information (producing a parietal effect) and reject all items that lack target-related information (see Elward and Wilding, 2010;Evans et al, 2010 for recent evidence). Consequently, the evidence from memory exclusion studies raises the possibility that the parietal ERP differences during RM might reflect strategic recollection of targeted sources.…”

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

“…In particular, these authors point to common activations in both kinds of tasks in the prefrontal cortex, which are described as being common control and monitoring mechanisms. Rather than straying too far into this promising avenue for further research, we confine our comments to how working memory mechanisms may be used in the exclusion task, and draw largely on the arguments proposed by Wilding and colleagues (Elward and Wilding, 2010;Elward et al, 2013). One observation is that intact recollection is not necessary at all, should sufficient capacity and reserve exist in a short-term store.…”

“…One recent development is the finding that the control component of recollection (i.e. as measured in exclusion tasks) draws heavily upon working memory resources (Elward & Wilding, 2010;Elward, Evans, & Wilding, 2013). Our view is that working memory resources would be necessary to hold in mind information at test and reflect metacognitively, or strategically upon it.…”