Topic Editors: Wai-Tat Fu (University of Illinois at Urbana-Champaign), Thomas Hills (University of Basel), & Peter Todd (Indiana University)
Search can be found in almost every cognitive activity, ranging across vision, memory retrieval, problem solving, decision making, foraging, and social interaction. Because of its ubiquity, research on search has had a tendency to fragment into multiple areas of cognitive science. The proposed topic aims at providing an integrative discussion of the central role of search from multiple perspectives. We focus on controlled search processes, which require (1) a goal, (2) uncertainty about the nature, location, or acquisition method of the objects to be searched for, and (3) a method for sampling through the search environment. While this definition of search is general and applicable to different domains, the specific search environments, strategies, and underlying cognitive and neural processes may differ. The goal of this issue is to compare and contrast search processes, in an effort to understand how structure, strategy, and process interact to generate search across different cognitive domains. We expect that given its cross-domain nature, the topic on search will be of broad interest to cognitive scientists including psychologists, behavioral ecologists, computer scientists, neuroscientists, linguists, and sociologists.
In reinforcement learning, a decision maker searching for the most rewarding option is often faced with the question: what is the value of an option that has never been tried before? One way to frame this question is as an inductive problem: how can I generalize my previous experience with one set of options to a novel option? We show how hierarchical Bayesian inference can be used to solve this problem, and describe an equivalence between the Bayesian model and temporal difference learning algorithms that have been proposed as models of human reinforcement learning. According to this view, search through the space of options is guided by abstract knowledge about
the relationships between di fferent options in an environment, resulting in greater search efficiency compared to traditional reinforcement learning algorithms previously applied to human cognition. In three behavioral experiments, we test several predictions of our model, providing evidence that humans learn and exploit structured inductive knowledge to make predictions about novel options. We suggest a new interpretation of dopaminergic responses to novelty in light of this model.
Optimal search in semantic memory
Searching through semantic memory may involve the use of several retrieval cues. In a verbal fluency task, such as naming as many
animal names as possible, the set of available cues could be the animal label, the just retrieved animal name, and the subcategory to
which that animal belongs. Individuals exhibit various patterns in their search behaviour, such as clustering animal names by
subcategory. In another task involving search in semantic memory, the remote associates task, RAT, three words are presented as cues and the task is to find a fourth word that is connected to all three words. The set of available cues are in the first instance the given triplet followed by the just-retrieved candidate answers. Whereas the task has been widely studied as a task of creative or insight problem solving, less research has been dedicated to the dynamic use of cues in RAT. In this paper, the RAT as a semantic retrieval task is studied and
compared to performance in the verbal fluency task. Three new experiments address the nature of cue combination, the influence of
cue duration, and the sequence of candidates generated by participants. A computational model of RAT performance is put forward in which different search algorithms are implemented and compared against the data. Preliminary findings suggest that search behaviour, including apparent discontinuities, reflect optimisation at the level of cue usage. Similarities and differences with the animal and information foraging literatures are discussed.
The Collective Outcome of Individual Decisions to Imitate or Innovate
People frequently search for solutions to problems in the context of peers who are searching for their solutions to the same problems. In these circumstances, people can either search for solutions on their own, or they can imitate the solutions found by others. We describe three experimental paradigms that explore the determinants of people’s decisions to either explore a problem space on their own or imitate others, and the impact that these decisions have on group-level outcomes. Results indicate that people tend to imitate: early within a search process, peers that are exploring similar solutions, better solutions, and solutions that are prevalent and becoming increasingly prevalent. These individual tendencies give rise to surprising group-level phenomena, including cases in which 1) giving searchers more information about peers’ solutions can decrease group-level performance, 2) giving searchers information about the quality of peers’ solutions decreases variability in the quality of solutions, and 3) searchers surrounded by imitative peers outperform searchers surrounded by less imitative peers.
Arthur B. Markman, Brian Glass, W. Todd Maddox, A. Ross Otto, & Bradley C. Love (University of Texas at Austin)
Motivation and search behavior
Many behaviors ranging from ordering meals from a restaurant to foraging in an environment can be characterized as a process of search through a space of possibilities. The fundamental tradeoff in search is between exploration (trying new opportunities in order to acquire additional information) and exploitation (focusing on regions where experience has yielded good outcomes). We review research suggesting that regulatory fit increases exploration. Regulatory fit occurs when there is a match between global and local rewards in an environment. We illustrate this influence of regulatory fit in repeated choice tasks in which exploration takes place in a space of decision outcomes as well as a foraging task in which exploration takes place in a two-dimensional space.
Search and the Aging Mind: The Role of Cognitive Control in Age Differences in Search
Search is a prerequisite for successful performance in a broad range of tasks from memory retrieval to making decisions between consumer goods. How does aging impact search processes in such disparate situations? Aging is associated with neuromodulatory and structural brain changes that underlie cognitive control processes, such as selective attention and working memory abilities, which are likely relevant to efficient search. We review the aging literature to evaluate the cognitive control hypothesis that predicts that age-related change in cognitive control processes underlies age differences in search. We focus on evidence from decision making, considering results from an array of tasks differing in complexity such as simple n-armed bandits, sequential decisions between many options, and more complex multi-attribute, multi--option decision making. Finally, we consider the limits of the cognitive control hypothesis, discussing whether auxiliary mechanisms such as age-related changes in strategies or motivational aspects are necessary to understand age-related changes in search.
Information Foraging across the Life Span: Search and Switch in Unknown Patches
The study examined the effects of task difficulty, patch heterogeneity and age on individual differences in information uptake and switch behavior in an information foraging task. 30 younger and 30 older participants had limited time to find words in a set of 4 word search puzzles on an electronic tablet that recorded performance, search time and switches between puzzles. There were three conditions: all easy, all puzzles containing high‐prototypical category exemplars in canonical orientations in the puzzle (forward, down); all difficult, puzzles containing low‐prototypical exemplars in any orientations (e.g., forward and backward diagonal); and mixed (2 easy, 2 difficult puzzles). Mixed effects modeling was used to estimate the rates of information gain (RIGs); i.e., cumulative number of words found as a function of time, for each participant. RIGs varied as a function of difficulty, bouts (i.e., attempts) and age. For example, younger adults had similar RIGs for difficult puzzles across bouts, but older adults showed a decrease in RIGs across bouts. At the same time, older adults persisted longer in the most difficult condition, which was adaptive in enabling them to achieve information uptake comparable to the younger adults. The revisit to the puzzles was especially adaptive for the hard puzzles and participants who switched more often. Older adults switched among information patches less often than younger ones suggesting that older adults tended to persist in the patch relatively longer when RIGs were dropping. Overall, the study suggests that age‐related strategic variation in information foraging is shaped by both individual capacity and environmental context.
Title and abstract coming soon...
Title and abstract coming soon...