Two-Point Discrimination for Upper Extremity and Face in Healthy Young Adults: A Cross-Sectional Study

Area of Science:

• Neuroscience
• Dermatology
• Clinical Sensory Science

Background:

• Two-point discrimination (TPD) quantifies tactile acuity.
• Establishing normal reference values is crucial for assessing sensory function.
• Variability in sensory perception needs to be understood within normal limits.

Purpose of the Study:

• To determine normative two-point discrimination (TPD) threshold values for the face and upper extremity.
• To provide reference data for healthy young adults aged 18-35 years.
• To establish a baseline for detecting potential sensory deficits.

Main Methods:

• Assessed static TPD thresholds in 67 healthy young adults (18-35 years).
• Measured eight skin areas on the face and dominant upper extremity using the method of limits with an aesthesiometer.
• Analyzed differences by gender (Mann-Whitney U test) and age (Spearman correlation).

Main Results:

• TPD values varied: 4.66-19.16 mm (face) and 1.33-68.66 mm (upper extremity).
• Fingertips and lateral mandible exhibited highest tactile sensitivity.
• No significant gender or age-related differences in TPD thresholds were observed.

Conclusions:

• TPD threshold values have clinical relevance for conditions affecting facial and upper extremity sensation.
• These normative data can assist in the early identification of sensory impairment.
• Provides a baseline for clinical assessment of tactile acuity.