Measurement of perception thresholds for electrical noise stimuli

Area of Science:

• Neuroscience
• Biomedical Engineering
• Sensory Physiology

Background:

• Sub-threshold electrical nerve stimulation (SENS) enhances tactile sensitivity.
• SENS is used for conditions like diabetes, stroke, and neuropathy.
• SENS efficacy relies on precise amplitude control relative to perception thresholds.

Purpose of the Study:

• Investigate factors influencing electrical perception thresholds.
• Determine if electrical perception thresholds are constant for SENS applications.
• Assess variability in electrical perception thresholds.

Main Methods:

• Employed a two-alternative forced-choice paradigm to measure electrical perception thresholds.
• Analyzed participant, noise frequency, electrode location, type, and impedance as factors.
• Re-tested thresholds under identical conditions to assess reliability.

Main Results:

• Electrical perception threshold is frequency-dependent.
• Thresholds showed significant variability unrelated to most tested factors.
• High variability observed even when re-tested under identical conditions.

Conclusions:

• Electrical perception thresholds are not constant for a given participant and electrode.
• The variability challenges the current application of SENS.
• Further research is needed to understand and account for threshold variability in SENS.