Frequency histograms of changes in lumbar trunk electronic von Frey mechanical activation response thresholds for the dorsal-ventral, 45° caudal, and 45° cranial directions of NS lateral thalamic neurons after time control (0-millisecond), 100-, and 400-millisecond HVLA-SM thrust durations. Note the shift to the right in the 45° caudal mechanical testing direction after both the 100-and 400-millisecond thrust durations. HVLA-SM, high velocity low amplitude spinal manipulation; NS, nociceptive specific.