A Simple Artifact-Rejection Preamplifier for Clinical Neurophysiology

ABSTRACT.

Artifacts from electrical or magnetic stimulation can easily overload the amplifiers used in clinical neurophysiology. Most circuits designed to reject stimulus artifact are cumbersome or usable only in special circumstances. I describe an artifact-rejection preamplifier, made from inexpensive parts and based on slew rate limiting, that can interface easily with commercial recording systems. The preamplifier allows successful recording of small and difficult signals such as magnetic sensory potentials and transcallosal cortical responses.

KEY WORDS.:

• Artifact
• neurophysiology
• stimulus