Searching Our Cognitive Social Networks: How We Remember Who We Know

Searching Our Cognitive Social Networks: How We Remember Who We Know Thomas T. Hills (thomas.hills@unibas.ch) & Thorsten Pachur (thorsten.pachur@unibas.ch) Department of Psychology, University of Basel, Missionsstrasse 64A, 4055, Basel, Switzerland Abstract Recalling people we know is a key cognitive function, influencing studies of contagious disease, how we see our relative position in the world, and who we invite to our weddings. Whereas social memory has often been studied independently from other memory research (e.g., Bond et al., 1985; Brewer et al., 1995), we focus here on possible parallels with search in other domains—in particular the thesis that search of social memory is governed by similar rules and processes as those that guide search in semantic memory and may involve executive processes. Such a connection would involve two claims: First, search in social memory dynamically transitions between local and global search strategies (similar to search of associative memory; SAM, Raaijmakers & Shiffrin, 1981). Second, as proposed for a domain general executive search process (Hills et al., 2010; Hills et al., 2008), dynamic transitions from local to global search criteria should recruit the general control of attention. We investigated these possibilities by modeling how people recall social contacts and also by investigating to what extent this search process correlates with working memory capacity. We examined the role of social categories, social proximity, and frequency factors as well as the dynamic character of search in social memory by developing a new task, the social fluency task, which asks participants to recall the first 35 ‘people that they know’. Participants then reconstructed the social network based on all pair-wise interactions between those 35 individuals (see Figure 1), and provided, for each recalled individual, their frequency of encounter with them as well as their social category (partner, family member, friend, or acquaintance). Participants also took a working memory span task, the automated operation span task (Unsworth et al., 2005). To disentangle the possible role of different retrieval structures, we compared several computational models that differed in the assumed cues governing the underlying sequential search process. We used a model framework similar to SAM (Raaijmakers & Shiffrin, 1981), which probes memory with a specific set of cues. Local cues were taken to represent social category or social proximity, based on the last item recalled. Frequency, being independent of recent recall, was taken as the global cue. We found that while—consistent with prior research (Bond et al., 1985; Brewer et al., 1995)—recall was structured in terms of social categories, models using social proximity and frequency information predicted participants’ recall patterns best. Furthermore, dynamic models that made local-to-global transitions where they were predicted by social proximity outperformed dynamic models making transitions predicted by social category. Finally, as proposed by a domain general executive search process, the observed dynamic transition rate between different retrieval structures was inversely correlated with working memory. Importantly, clustering coefficient for individual social networks did not differ in relation to operation span. Our results highlight a neglected parallel between semantic and social memory, and support the thesis of a domain-general executive search process that directs search by maintaining perseveration on local subgoals while inhibiting competition from other potential goals (i.e., targets of attention). References and Relevant Publications Bond, C. E, Jr., Jones, R. L. , & Weintraub, D. L. (1985). On the unconstrained recall of acquaintances: A sampling- traversal model. Journal of Personality and Social Psychology, 49, 327-337. Brewer, D. D. , Rinaldi, G. , Mogoutov, A. , & Valente, T. W. (1995). A quantitative review of associative patterns in the recall of persons. Journal of Social Structure, 6(1). Hills, T. (2006). Animal foraging and the evolution of goal- directed cognition. Cognitive Science, 30, 3-41. Hills, T. (In press). The evolutionary origins of cognitive control. Topics in Cognitive Science. Hills, T. , Goldstone, R.L. , & Todd, P.M. (2008). Evidence for generalized cognitive search processes at multiple levels in a hierarchical problem solving task. In V. Sloutsky, B. Love, and K. McRae (Eds.) Proceedings of the 30th Annual Conference of the Cognitive Science Society (pp. 843). Mahwah, NJ: Lawrence Erlbaum. Hills, T. , Todd, P. M. , & Goldstone, R. L. (2008). Search in internal and external spaces: Evidence for generalized cognitive search processes. Psychological Science, 19, Hills, T. , Todd, P. M. , & Goldstone, R. L. (2010). The central executive as a search process: exploration and exploitation in generalized cognitive search processes. Journal of Experimental Psychology: General, 139, 590- 609. doi: 10.1037/a0020666. Hills, T. , Todd, P.M. , & Jones, M. (2009). Optimal foraging in semantic memory. In N.A. Taatgen & H. van Rijn (Eds.), Proceedings of the 31st Annual Conference of the Cognitive Science Society. Cognitive Science Society. Raaijmakers, J. G. W. , & Shiffrin, R. M. (1981). Search of associative memory. Psychological Review, 88, 93-134. Unsworth, N. , Heitz, R.C. , Schrock, J.C. , & Engle, R.W. (2005). An automated version of the operation span task. Behavior Research Methods, 37, 498–505.