Check for updates Original Article Survival processing eliminates collaborative inhibition Matthew B Reysen, Heather Bliss and Melissa A Baker QJEP Quarterly Journal of Experimental Psychology 2018, Vol. 71(6) 1340-1347 Experimental Psychology Society 2017 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1080/17470218.2017.1318408 cjep.sagepub.com SSAGE Abstract The present experiments examined the effect of processing words for their survival value, relevance to moving and pleasantness on participants' free recall scores in both nominal groups (non-redundant pooled individual scores) and collaborative dyads. Overall, participants recalled more words in the survival processing conditions than in the moving and pleasantness processing conditions. Furthermore, nominal groups in both the pleasantness condition (Experiment I) and the moving and pleasantness conditions (Experiment 2) recalled more words than collaborative groups, thereby replicating the oft-observed effect of collaborative inhibition. However, processing words for their survival value appeared to eliminate the deleterious effects of collaborative remembering in both Experiments 1 and 2. These results are discussed in the context of the retrieval strategy disruption hypothesis and the effects of both expertise and collaborative skill on group remembering. Keywords Survival processing; collaborative recall Received: 30 June 2016; revised: 13 February 2017; accepted: 23 March 2017 When we remember details from the past, such reminis- cences often occur in the presence of, and in collaboration with, other people. Although the vast majority of research on the topic of human memory has comprised situations in which individual participants study a set of information and are subsequently tested in one form or another on their own, the topic of how social influences can impact mem- ory performance has recently received an increased level of attention (Harris, Paterson, & Kemp, 2008; Hirst & Echterhoff, 2012). One such phenomenon, referred to as collaborative inhibition, occurs when the combined output of two or more participants remembering individually (a nominal group) surpasses that of an equal number of participants remembering collectively (Weldon & Bellinger, 1997). In other words, despite the common misconception that working collaboratively with a partner to recall events will enhance memory, the opposite is often true. For example, if one really wanted to remember as many items as possi- ble from a previously studied word list, two participants might be better off remembering as many of the words as they could on their own, and only then combining those list items with their partner's recall output. Collaborative inhibition is a robust phenomenon observed in a number of experimental situations with a variety of different stimuli (Rajaram & Pereira-Pasarin, 2010). However, despite the pervasiveness of the effect, there are certain situations that can reduce, eliminate or even reverse collaborative inhibition. Instances of collabo- rative facilitation, or the observation of an increase in recall as a result of collaboration, have not been observed fre- quently. In one such example, several older married cou- ples remembered more information when working together than their combined individual accounts of events (Harris, Keil, Sutton, Barnier, & Mcilwain, 2011). However, this outcome did not occur for all couples and appeared to be restricted to cases in which they employed a shared retrieval strategy. Thus, even when some couples had known each other for decades and were presented with ecologically valid stimuli (e.g., autobiographical materials), collabora- tive inhibition was still observed. One clear example of collaborative facilitation was demonstrated in a study that examined the effects of exper- tise on group remembering (Meade, Nokes, & Morrow, 2009). In that study, expert pilots worked together to recall Department of Psychology, University of Mississippi, University, MS, USA Corresponding author: Matthew B Reysen, Department of Psychology, University of Mississippi, University, MS 38677, USA. Email: reysen@olemiss.edu Reysen et al. aviation scenarios, and their memory output was compared to those of both novice pilots and non-pilots. Meade et al. found that although groups of novice pilots and non-pilots suffered from collaborative inhibition, the expert pilots actually remembered more when working together than when their individual accounts were combined to form nominal groups. They hypothesized that both domain knowledge (Ericsson, Charness, Feltovich, & Hoffman, 2006) and collaborative skill (Ekeocha & Brennan, 2008; Sutton, 2013) contributed to the observed facilitation. While domain knowledge refers to a reservoir of facts per- tinent to completing the task at hand, collaborative skill refers to the case and effectiveness with which coworkers can share task-relevant information. For the expert pilots who participated in Meade et al.'s (2009) study, it appears that possessing both of these attributes improved their joint recall efforts to the point where remembering together actually became a beneficial endeavor. Collaborative inhibition can be explained, at least in part, by the retrieval strategy disruption hypothesis (Basden, Basden, Bryner, & Thomas, 1997; Dahlstrm, Danielsson, Emilsson, & Andersson, 2011). According to this view, a participant's optimal, but idiosyncratic, retrieval strategy can be disrupted by the presence of another person's recall output. Thus, to the extent that retrieval strategy disruption can be minimized (through a shared retrieval strategy or otherwise), collaborative inhibition might be expected to decrease. In the case of collaborative facilitation noted above, it is likely that high levels of domain knowledge, present among the expert pilots but absent in other participants, contributed to a more synchronized retrieval strategy (Meade et al., 2009). If a topic area could be identified in which many or most participants were "experts" with a high and innate level of domain knowledge, it might be possible to replicate such effects even in the absence of any advanced training. According to a review of the research literature on col- laborative inhibition (Harris et al., 2008), Meade et al.'s (2009) results demonstrating collaborative facilitation rep- resent the exception rather than the norm (see also Nokes- Malach, Meade, & Morrow, 2012 for an example related to problem-solving). One purpose of this study was to deter- mine whether stimuli processed in accordance with a fit- ness-relevant task might reduce or even eliminate collaborative inhibition. In other words, we sought to determine whether there are certain topics for which all of us contain sufficient domain knowledge to render collabo- rative retrieval efforts less harmful. One mechanism by which fitness-relevant processing scenarios might lead to such results is by promoting the use of more similar retrieval strategies at the point of test. Any increase in the tendency to recall items in a similar manner might be expected to reduce retrieval strategy disruption and, in turn, improve recall performance. Another goal of this 1341 study was to determine whether explicit training in col- laborative skill is necessary to facilitate recall during a col- laborative memory task. Experiment was designed to directly address these issues by comparing nominal and group recall perfor- mance following a deep processing task clearly devoid of fitness relevance (pleasantness processing) with perfor- mance following an ostensibly fitness-relevant task (sur- vival processing). The survival processing paradigm, originally devised by Naime, Thompson, and Pandeirada (2007), usually involves asking participants to rate words with respect to the extent to which those words could aid in a survival situation. For example, participants may be asked to rate the usefulness of common nouns in terms of finding food and shelter and avoiding predators while stranded in a grassland environment. A survival processing advantage occurs when partici- pants recall more words following survival processing than after performing other encoding tasks that are not fit- ness-relevant (Nairne, Pandeirada, & Thompson, 2008). Although the survival processing effect has not been observed for implicit processing tasks (Mcbride, Thomas, & Zimmerman, 2013), memory for faces (Savine, Scullin, & Roediger, 2011) or certain paired associate learning tasks (Schwartz & Brothers, 2014), the effect is relatively robust. The survival processing effect has been observed in a number of situations, including using pictures (Otgaar, Smeets, & Bergen, 2010), in children (Aslan & Buml, 2012) and following an extended delay (Raymackers, Otgaar, & Smeets, 2013). Furthermore, although several proximate accounts for the effect have been hypothesized, including self-referential processing, planning and elabo- ration (see Kazanas, 2015 for a review), Nairne and col- leagues have asserted that the ultimate cause is that our memory systems are "tuned" to remember fitness-relevant information (Naime & Pandeirada, 2010). As such, use of the survival processing paradigm in a collaborative memory context provides an opportunity to examine the effect of domain knowledge on recall while utilizing neutral word lists as stimuli. In Experiment 1, participants were asked to encode a list of words while engaging in either pleasantness processing or survival processing. Following this, participants completed a free recall test alone or while working together in pairs. The primary research hypothesis was that the inhibitory effects of collaborative inhibition would be observed in the pleasantness processing condition, but would be either eliminated or reversed in the survival processing condition. In other words, if survival processing repre- sents an area of innate domain knowledge accessible to us all, at least one important component of the advantage enjoyed by the expert pilots in Meade et al.'s (2009) study would be available to the participants in this study who encoded the word lists in terms of their relevance to a survival scenario. 1342 Experiment I Method Participants. In total, 200 undergraduate psychology stu- dents from the University of Mississippi participated in the experiment in return for partial course credit. Design and materials. A 2 (encoding condition: pleasant- ness vs survival) x 2 (retrieval condition: individual vs collaborative) between-subjects design was employed, with 50 participants included in each of the four experi- mental conditions. In the initial phase of the experiment, participants were asked to rate 30 unrelated common nouns selected from Van Overschelde, Rawson, and Dun- losky's (2004) list of category norms. Half of the partici- pants rated words with respect to their relevance in a survival situation, whereas other participants rated the pleasantness of the words. The instructions for both the survival and pleasantness tasks were identical to those used by Nairne et al. (2008). More specifically, an experi- menter read the following instructions to participants in the pleasantness conditions: In this task, we are going to show you a list of words, and we would like you to rate the pleasantness of each word. Some of the words may be pleasant and others may not, it's up to you to decide. (Naime et al., 2008, p. 177) In addition, the survival instructions were as follows: In this task, we would like you to imagine that you are stranded in the grasslands of a foreign land, without any basic survival materials. Over the next few months, you'll need to find steady supplies of food and water and protect yourself from predators. We are going to show you a list of words, and we would like you to rate how relevant each of these words would be for you in this survival situation. Some of the words may be relevant and others may not, it's up to you to decide. (Naime et al., 2008, p. 177) All stimuli were presented and all responses were recorded using personal computers. Procedure. Participants arrived at the lab in pairs and were seated in separate cubicles containing personal computers. Other than the two participants, the experimenter was the only other person in the room. After signing an informed consent form, the participants listened to the experimenter who read a set of instructions that informed them that they would be asked to rate a list of words on a scale ranging from 1 (totally unpleasant/irrelevant) to 5 (extremely pleasant/relevant). The participants were asked to rate the words with respect to either the pleasantness of each word or the word's relevance to a survival situation, depending on the encoding condition to which they had been ran- domly assigned. They were told that during each trial, a Quarterly Journal of Experimental Psychology 71(6) word would appear on the computer screen with a rating scale beneath it. They were asked to type a numerical response ranging from 1 to 5, at which point the word and their response would remain on the screen until the presen- tation of the next word. Participants were encouraged to attempt to use the entire rating scale while rating the words. The participants completed five practice trials prior to rating the experimental stimuli to get them acquainted with both the procedure and the timing of the rating task. During cach trial, a word was presented for 5s. At the conclusion of each 5-s presentation, a 0.5-s interstimulus interval pre- ceded the presentation of the next word. After each partici- pant rated the five practice words, the experimenter asked them whether they had any further questions about the rat- ing task. After answering any remaining questions, the experimenter asked participants to press the "enter" key to begin the experiment. At that point, the process of word presentation, coupled with each participant providing a numerical rating, continued until each participant had rated all 30 stimulus items. After rating the last word on the list, participants were asked to complete simple addition and subtraction prob- lems for 60s. Following this distractor task, the recall por- tion of the experiment commenced. In the individual recall condition, participants were asked to type as many of the previously rated items as possible. Each item that partici- pants typed remained on the screen for the duration of the recall task. In the collaborative recall condition, one par- ticipant was asked to slide his or her chair beside their part- ner's chair so that both participants were situated in front of one computer screen. Next, participants were asked to work together to remember as many of the previously rated words as possible. One participant typed the responses as both participants worked together to remem- ber words from the list. When participants indicated that they were no longer capable of recalling any more items from the list, they were debriefed and thanked for their participation. Both the incidental individual and collabora- tive recall tests were self-paced. Results and discussion In the present experiment, the primary dependent measure of interest was participants' free recall scores, which are displayed in Figure 1. Intrusions were rare, representing less than 1% of the recalled items, and are not discussed further. Representative nominal groups were formed using the process outlined by Kelley and Wright (2010). A 2 (encoding condition: pleasantness vs survival) x 2 (retrieval condition: individual vs collaborative) analysis of variance (ANOVA) revealed statistically significant main effects for both encoding condition, F(1,96)=42.06, mean squared error (MSE)=9.04, p