Eyes wide open: enhanced pupil dilation when selectively studying important information

Abstract

Remembering important information is imperative for efficient memory performance, but it is unclear how we encode important information. The current experiment evaluated two non-exclusive hypotheses for how learners selectively encode important information at the expense of less important information (differential resource allocation and information reduction). To evaluate these hypotheses, we measured changes in learners’ pupil diameter and fixation durations while participants performed a selectivity task that involved studying lists consisting of words associated with different point values. Participants were instructed to maximize their score on a free recall task that they completed after studying each list. Participants’ pupils dilated more when studying high-valued than low-valued words, and these changes were associated with better memory for high-valued words. However, participants fixated equally on words regardless of their value, which is inconsistent with the information reduction hypothesis. Participants also increased their memory selectivity across lists, but changes in pupil diameter and differences in fixations could not account for this increased selectivity. The results suggest that learners allocate attention differently to items as a function of their value, and that multiple processes and operations contribute to value-directed remembering.

Adaptive scaling of reward in episodic memory: a replication study

“…These effects have been shown using a variety of memory tests including free and serial recall, and recognition memory (Adcock et al, 2006;Eysenck & Eysenck, 1982;Harley, 1965;Loftus & Wickens, 1970;Madan, Caplan, Lau, & Fujiwara, 2012;Spaniol, Schain, & Bowen, 2013;Wolosin, Zeithamova, & Preston, 2012). Furthermore, these findings extend to value-based learning where points are used instead of monetary incentives (Ariel & Castel, 2014;Castel, 2007;Castel, Benjamin, Craik, & Watkins, 2002;Castel, Murayama, Friedman, McGillivray, & Link, 2013;Friedman & Castel, 2011;Soderstrom & McCabe, 2011). Taken together these findings suggest that people are acting to maximize reward and are able to allocate cognitive resources during learning so that higher value items are better encoded than lower value items.…”

Effects of aging on value-directed modulation of semantic network activity during verbal learning

“…Each of the two full practice lists included recall tests with feedback. Prior work has shown that selectivity is typically stronger on the third and subsequent lists than on the first two lists (Ariel and Castel, 2014; Castel, 2008; McGillivray and Castel, 2011). Thus, we assumed that by presenting two full lists prior to scanning, strategy use would be relatively well established and consistent in the scanner.…”

Value-based modulation of memory encoding involves strategic engagement of fronto-temporal semantic processing regions

“…Each of the two full practice lists included recall tests with feedback. Prior work has shown that selectivity is typically stronger on the third and subsequent lists than on the first two lists (Ariel & Castel, 2014; Castel, 2008; McGillivray & Castel, 2011). Thus, we assumed that by presenting two full lists prior to scanning, strategy use would be relatively well established and consistent in the scanner.…”

“…The VDR paradigm involves having participants study a list of words paired with point values, with the participants’ goal being to maximize the total score, which is the sum of the values associated with recalled words. A number of behavioral studies (e.g., Ariel & Castel, 2014; Castel et al, 2002; Castel, Farb, & Craik, 2007; Castel, Murayama, Friedman, McGillivray, & Link, 2013; Hanten et al, 2007; Loftus & Wickens, 1970; Soderstrom & McCabe, 2011; Watkins & Bloom, 1999) have shown that words that are arbitrarily determined to be valuable (via high point values) tend to be recalled better than words that are arbitrarily assigned lower values. However, prior studies with this paradigm have been limited in fully explaining the effect on a mechanistic level, with explanations ranging from differential forms of rehearsal, use of imagery, and strategic encoding and retrieval operations.…”