Why does saccade execution increase episodic memory retrieval? A test of the top-down attentional control hypothesis

Abstract

Making repetitive saccadic eye movements has been found to increase subsequent episodic memory retrieval and also to increase subsequent top-down attentional control. We theorise that these effects are related such that saccade-induced changes in attentional processing facilitate memory retrieval. We tested this idea by examining the effect of saccade execution on retrieval conditions that differed in relative ease of consciously accessing episodic memories. Based on recent theories of episodic retrieval, we reasoned that there is a larger role for top-down attention when memories are more difficult to access. Consequently, we expected saccade execution to have a greater facilitative effect on retrieval when memories were more difficult to access. We obtained the expected result in a recall procedure in Experiment 1 and in a recognition procedure in Experiment 2. We also examined an individual difference factor--consistency of handedness--as a possible moderator of saccade execution effects on retrieval. We discuss how our top-down attentional control hypothesis can be extended to explain beneficial effects of saccade execution on other types of cognition, as well as negative effects on retrieval in some cases.

Re-evaluating whether bilateral eye movements influence memory retrieval

“…Lyle and Edlin performed this experimental manipulation because it has been shown in the literature that top-down attentional processes play a key role in memory tests, especially when performance is low and cognitive effort is high [34]. Results aligned with their predictions: The SIRE benefit was found when memory tasks were harder and therefore required greater top-down attentional control [28]. Crucially, they also found a memory performance benefit following vertical eye movements (for the second time), which is predicted only by their top-down attentional control account.…”

“…It has been shown that unilateral saccades activate the contralateral hemisphere [27]. In the context of SIRE, this would suggest that vertical eye movements should not produce a SIRE effect because they do not produce the same bilateral activation in frontal eye fields as is produced by horizontal eye movements [22,28]. In summary, the interhemispheric interaction hypothesis predicts that only horizontal eye movements should result in a performance benefit due to the inherent alternating activation of hemispheres.…”

“…In 2015, Lyle and Edlin evaluated this attention idea again, opting to employ both horizontal and vertical eye movement conditions, along with a return to more common memory retrieval tests (namely, recall and recognition) instead of the attention test used previously [28]. Critically, some items on the recall test were made more difficult than others by first having participants practise recall from certain studied semantic categories but not from others.…”

“…It is worth noting that Lyle and Edlin's (2015) top-down attentional control theory did not consider right-versus left-handedness; instead, they stated that consistent handedness (often considered to be a score of 0.80 or greater on the Edinburgh Handedness Index) is the truly important factor [28]. They argued that only consistent handers seem to benefit from bilateral eye movements, but unfortunately they did not provide a solid prediction as to why this handedness inconsistency occurs [28].…”

Replication Requires Psychological Rather than Statistical Hypotheses: The Case of Eye Movements Enhancing Word Recollection

“…Other influential accounts, primarily for EMDR, such as the working memory account (Andrade et al, 1997) or the orienting response account (Armstrong and Vaughan, 1996; Stickgold, 2002), as well as the newer top-down attentional control account from the SIRE domain (Edlin and Lyle, 2013; Lyle and Edlin, 2015) were completely ignored. Elsewhere (Phaf, submitted), I have identified crucial hidden variables based on the linking of theoretical accounts for SIRE and EMDR that may well explain the contrast between the original SIRE findings and the non-replication.…”