Biomedical subjects

Christofer J Edwards

Publications and source records attributed to Christofer J Edwards.

2 recordsLinked to original sources

PubMed2005

Pulse rise time but not duty cycle affects the temporal selectivity of neurons in the anuran midbrain that prefer slow AM rates.

Recovery-type auditory neurons in the anuran inferior colliculus (IC) respond with band-pass or low-pass selectivity for sinusoidal AM. These cells respond to each modulation cycle at slow AM rates and respond only at the onset of fast AM or pulse repetition rate (PRR) stimuli, failing to recover from the effects of early pulses. This selectivity is not altered by changes in pulse duty cycle. The recovery process is governed therefore by the interpulse interval and not the dimension of the gap between sound pulses. Most of these neurons preferred fast rise times, which is characteristic of the sound pulses in the calls of Hyla regilla and Rana pipiens, the two species selected for this study.

Acoustic Stimulation↗

PubMed2002

Auditory midbrain neurons that count.

Many acoustic communication signals, including human speech and music, consist of a precise temporal arrangement of discrete elements, but it is unclear whether this precise temporal patterning is required to activate the sensory neurons that mediate signal recognition. In a variety of systems, neurons respond selectively when two or more sound elements are presented in a particular temporal order and the precise relative timing of these elements is particularly important for 'delay-tuned' neurons, including 'tracking' types, in bats. Here we show that one class of auditory neurons in the midbrain of anurans (frogs and toads) responds only to a series of specific interpulse intervals (IPIs); in the most selective cases, a single interval that is slightly longer or shorter than the requisite interval can reset this interval-counting process.

Acoustic Stimulation↗