Current Research Program

Below are brief descriptions of some of the current lines of work I am pursuing.

Context Effects in Repetition and Semantic Priming

Repetition priming refers to the findings that recent exposure to a stimulus increases the speed and accuracy with which the same stimulus is recognized on a subsequent encounter. Accounts of repetition priming predict facilitation for recently and frequently encountered stimuli. Thus, to the extent that participants are exposed to the target concepts in the environment, these concepts should be primed. Models of priming that rely on an activation mechanism predict that attending to stimuli in the environment will result in increased activation of these items. To the extent that activation is not constrained by contextual changes, reliable facilitation is expected to occur for targets that match the events ongoing in the environment (i.e., leprechaun should be more activated around mid-March than at other points during the year).  The important theoretical issue here is that one might have leprechaun activated at a low level even without consciously thinking about that concept.

In another study, I am examining how people respond to individuals who are currently receiving considerable attention in the media. I have been conducting this study over the past several months and am tracking how people’s responses to political figures like Hillary Clinton or Mike Huckabee change as a function of their coverage in the media and their polling data. One question is whether increased familiarity with an individual affects how much they are liked and how quickly people can access information about them. Furthermore, this research addresses if and how what people are exposed to in their everyday life influences their performance in laboratory tasks that tap simple activation processes.

            Semantic memory refers to the storehouse of general world knowledge each individual has. For example, your knowledge that cats and dogs are common household pets is part of your semantic memory. Semantic priming refers to the facilitation observed when a target word (e.g., dog) is preceded by a related prime (e.g., cat) compared to an unrelated prime (e.g., cut). I’m particularly interested in how new information becomes embedded into an individual’s pre-existing knowledge. One idea is that repeated exposure to information in different contexts will increase the likelihood information is going to become part of world knowledge. The way in which I am measuring this is by seeing whether pairs of words, like snakes-plane or patriot-act, result in priming the same way cat and dog do.

Influences of Semantic and Phonographic Similarity on Memory Accuracy

            The Deese-Roediger-McDermott (DRM) paradigm is a powerful tool for investigating memory errors and the underlying processes involved in what type of information individuals can remember. The primary finding from this paradigm is that individuals reliably misremember the occurrence of a critical, non-presented item after studying lists of similar items. For example, after studying a list of words such as bed, rest, tired, awake, dream, etc., people often remember that sleep was also on the list, even when it was not. One account is that this occurs because activation spreads along pre-existing semantic and lexical connections, thereby increasing the familiarity or accessibility of the critical item. I am currently examining the limits of a spreading activation mechanism in accounting for memory errors and further clarifying what additional processes are critical for explaining this powerful memory illusion.
           

Learning of Complex Natural Categories in Adulthood

            Investigations of how individuals learn about categories is often conducted using abstract, artificial stimuli that are impoverished relative to real-world objects. Whereas such stimuli allow for substantial experimental control, and have been essential in understanding category and concept learning, one concern is the potential lack of generalizability. In addition, the majority of research has focused on children and young adults. In a series of studies on natural BIRD categories, I am investigating how adults learn complex natural categories in an experimental setting, and second, whether older adults could learn these categories as well as young adults.