Ch9. Sequence Detection

Alternative serial-order mechanism Sequence Detector with Mediator Summarization Alternative serial-order mechanism Sequence Detector with Mediator Mediator : a third element to both representations of elementary events Aspects Movement Detection For Word Strings Syntactic Structure

Mediator of sequence detection Movement Detection Mediator of sequence detection Movement Detection A third neuron γ responds to the sequential stimulation of α and β, but not to the reverse sequence. The mechanism involves low-pass filtering of the signals to delay or stretch In visual systems of insects , mammals, and cerebellar systems Extra third-party elements vs. direct sequence (both) A A α γ B B β

Sequence Detectors for Word Strings Mediated sequence detection may be relevant for processing the serial order of words. Not equal to the visual systems Time domain differences Time scale Problem Number of represented sequences : too many detectors responding to a particular sentence Categorization : word categories(word webs) Generalization α1 β1  α2β2  AB  α2β1 Variable Delays Peter comes / Peter, the singer, comes / Peter, the world wide famous singer, comes …

Sequence Detectors and Syntactic Structure Tree construction Within-tree transport of features Disadvantage in representation Syntactic Model based on Sequence Detectors Pronoun-verb Verb-verb suffix Pronoun-verb suffix Syntactic Priming Ex) double object setence Sequence Detectors on categories of word representations  Sequences of words from lexical categories He come s Ppr V Vs Np Vp S Lexical Categories Syntactic Categories He come s Word webs Sequence Detectors

Researches on Neural Network Conclusion Researches on Neural Network Single layer Multi-layers Direct Sequence Detector vs. Mediated Sequence Detector Mediated Sequence Detector A variety of delay range Mediator