{"title":"An adaptable CMOS depressing synapse with detection of changes in input spike rate","authors":"Yilda Irizarry-Valle, A. C. Parker, N. Grzywacz","doi":"10.1109/LASCAS.2014.6820322","DOIUrl":null,"url":null,"abstract":"Sensory pathways in the brain attain large dynamic ranges and novelty detection through adaptive mechanisms. We present a CMOS neuromorphic circuit emulating the adaptation dynamics of short-term depressing synapses for both transient and steady state. The circuit detects abrupt changes in the input firing rate following the Weber-Fechner relation, where the transient response is proportional to the fractional change of the input firing rate. In the steady state, the input-output relationship follows the one over frequency law in the excitatory postsynaptic potential (EPSP) amplitude. The circuit also detects novel change after a long interval of inactivity. The design comprises a small number of transistors, while capturing the desired input-output relationship. The amplitude of both transient and steady state EPSP are tunable. To our knowledge this is the first CMOS design to approach the Weber-Fechner relation.","PeriodicalId":235336,"journal":{"name":"2014 IEEE 5th Latin American Symposium on Circuits and Systems","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2014-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"2","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"2014 IEEE 5th Latin American Symposium on Circuits and Systems","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1109/LASCAS.2014.6820322","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 2
Abstract
Sensory pathways in the brain attain large dynamic ranges and novelty detection through adaptive mechanisms. We present a CMOS neuromorphic circuit emulating the adaptation dynamics of short-term depressing synapses for both transient and steady state. The circuit detects abrupt changes in the input firing rate following the Weber-Fechner relation, where the transient response is proportional to the fractional change of the input firing rate. In the steady state, the input-output relationship follows the one over frequency law in the excitatory postsynaptic potential (EPSP) amplitude. The circuit also detects novel change after a long interval of inactivity. The design comprises a small number of transistors, while capturing the desired input-output relationship. The amplitude of both transient and steady state EPSP are tunable. To our knowledge this is the first CMOS design to approach the Weber-Fechner relation.