Beyond Pattern Completion with Short-Term Plasticity
- Kevin Shabahang, School of Psychological Sciences, University of Melbourne, Melbourne, VIC, Australia
- Hyungwook Yim, School of Psychological Sciences, The University of Melbourne, Melbourne, Australia
- Simon Dennis, School of Psychological Sciences, The University of Melbourne, Melbourne, VIC, Australia
AbstractIn a Linear Associative Net (LAN), all input settles to a single pattern, therefore Anderson, Silverstein, Ritz, and Jones (1977) introduced saturation to force the system to reach other steady-states in the Brain-State-in-a-Box (BSB). Unfortunately, the BSB is limited in its ability to generalize because its responses are restricted to previously stored patterns. We present simulations showing how a Dynamic-Eigen-Net (DEN), a LAN with Short-Term Plasticity (STP), overcomes the single-response limitation. Critically, a DEN also accommodates novel patterns by aligning them with encoded structure. We train a two-slot DEN on a text corpus, and provide an account of lexical decision and judgement-of-grammaticality (JOG) tasks showing how grammatical bi-grams yield stronger responses relative to ungrammatical bi-grams. Finally, we present a simulation showing how a DEN is sensitive to syntactic violations introduced in novel bi-grams. We propose DENs as associative nets with greater promise for generalization than the classic alternatives.