Silicon neurons that phase-lock

Abstract—We present a silicon neuron with a dynamic, active leak that enables precise spike-timing with respect to a time-varying input signal. Our neuron models the mammalian bushy cell, which enhances the phase-locking of its acoustically driven inputs. Our model enhances phase-locking by up to 38% (quantified by vector strength) across a 60 dB range of acoustic intensities, and up to 22% over a passive leak. Its conductancebased log-domain design yields a compact and efficient circuit, fabricated in 0.25 µm CMOS, that is an ideal timing-enhancing component for neuromorphic speech recognition systems. I. IMPROVING SPEECH RECOGNITION SYSTEMS Automatic speech recognition (ASR) has been sought by engineers for more than 50 years [1]. Unlike human speech recognition, which degrades gracefully under progressively deteriorating acoustic conditions, ASR systems are sensitive to variance in the sound source and to background noise. In contrast, human listeners improve recognition in noi...

• Type: Conference
• Year: 2006
• Where: ISCAS
• Authors: J. H. Wittig Jr., Kwabena Boahen
• Keywords: Asr Systems, ISCAS 2006, Speech Recognition, Speech Recognition Systems