FIG. 3.

Electrical perceptual threshold (EPT) vs. International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) in representative spinal cord injury (SCI) participants. EPT values and Z-scores are shown in representative SCI participants (gray circles, left and right graphs, respectively) compared with control subjects (black circles, left graphs). Note that a Z-score represents the distance between the raw score and the population mean in units of the standard deviation. A positive Z-score indicates that the raw score is above the mean. Dashed lines in each graph represent values 2 standard deviation from the mean of sex and age-matched controls. ISNCSCI sensory level is shown by a horizontal black line, and the EPT level is shown by a horizontal gray line. In the SCI participant with acute SCI (A, gray circles), the EPT and Z-scores showed a bilateral asymmetric sensory impairment located two (left side) and three (right side) spinal segments above the ISNCSCI sensory level as shown by the difference between the black and gray lines. In the participant with chronic SCI (B, gray circles), the EPT and Z-scores showed a bilateral asymmetric sensory impairment below dermatome T3 on the left side and T2 on the right side. In the participant with extended-chronic SCI (C, gray circles), the EPT and the Z-score analysis revealed significant bilateral symmetric deviations of EPT values from the mean of control subjects from C5. Thus, EPT and ISNCSCI sensory levels were located at the same spinal segment.