Large-Scale Modeling of the Lexicon. We are building a connectionist model of lexical processing that includes over 45,000 English words. The theoretical principles and technological innovations of the model represent a synthesis of the various lines of work in the lab.

Input Gain. Double dissociations are usually interpreted as evidence for fixed, architectural divisions in the cognitive system. We are working on an alternative conceptualization in which double dissociations arise from qualitative changes in the dynamics of processing. We are using connectionist models to explore and test this alternative.

Power Law Behavior. Evidence is mounting that fluctuations in human behavior, like many other phenomena in nature, exhibit temporal dependencies over multiple time scales (i.e., 1/f or pink noise). We are studying these fluctuations to determine their source, and to understand their implications for the nature of cognitive processing.

Tempo Tasks. The coordinated timing of human behavior is evident everywhere we look. Cognitive processes must also be coordinated in time, but little is known about how such coordination is achieved. In tempo tasks, we use metronomes to engage the timing of cognition, and we use measures of behavior to investigate the underlying mechanisms of control.

Phonological Development. In the first few years of life, children learn about the sounds of their native language. We are building a connectionist model of this process to test the idea that phonological knowledge emerges from the task contraints of spoken word comprehension, production, and imitation.