Memory Research

Our research in the area of memory has focused on aspects of recognition memory, memory monitoring (judgments of learning, and confidence judgments), and more recently on understanding how people decide to terminate memory search.

Decisions to terminate search are characteristic of both everyday retrieval tasks (e.g, recollecting who was at a recent party you attended or what movies are currently playing at the theater), as well as retrieval tasks required in professional domains (e.g., the retrieval of potential diagnostic hypotheses by a physician). Search termination is also characteristic of participants’ responses to many survey questions. For example, asking participants ‘How many alcoholic beverages did you consume in the last week?’ may entice participants to retrieve and count past episodes of drinking. Obviously, the participant must terminate search prior to responding.

Given the ubiquity, and necessity, of a self-terminating memory search process, it is unsurprising that most process-models of memory include stopping rules. What is surprising, however, is the dearth of studies investigating the psychological basis of how people terminate memory search. In fact, there has not even been an assessment of whether search termination decisions follow any systematic or lawful pattern, let alone an assessment of the psychological and task variables that might moderate people’s decisions to terminate memory search. Yet, the fact that models of memory include stopping rules pre-supposes that the stopping behavior of individuals is indeed lawful.

Our research addresses three questions:

  1. Is the decision to terminate memory search systematic across both individuals and tasks?
  2. Is the decision to terminate search affected by ones affective or motivational state? and
  3. Is the decision to terminate search related to individual differences variables?

To study search termination decisions, we developed a modified free-recall task in which the participant decides when he or she is finished retrieving (see Figure), rather than allotting each subject a preset amount of time. Although a seemingly trivial, this methodological change provides three new reaction time measures needed to assess search termination decisions.

Modified free recall paradigm

The most important of these is termed 'Exit Latency' (EL), which is defined as the time between the last retrieved item, and the participants decision to terminate memory search.

To date, our research has yielded three important findings: