A simple method for estimating conduction velocity of the spinothalamic tract in healthy humans.
OBJECTIVE
The object of this study was to establish a method for estimating the conduction velocity (CV) of the spinothalamic tract (STT) in relation to clinical application.


METHODS
The CV of the STT was estimated by an indirect method based on that reported by Kakigi and Shibasaki in 1991 (Kakigi R, Shibasaki H. Electroenceph clin Neurophysiol 80 (1991) 39). Laser-evoked potentials (LEP) were measured in 8 subjects following hand (LEPH) and foot (LEPF) laser stimulation. The conduction times recorded at the scalp (P340, P400 and N150 potentials) were considered as the summation of peripheral and central components. The peripheral conduction times were calculated by measuring the latency of the electrical cutaneous silent period (from the same stimulus site of LEPs), corrected for F- and M-wave latency values.


RESULTS
The CV of the STT ranged between 8.3 and 11.01 m/s and its mean value was found to be approximately 9.87+/-1.24 m/s. The CV of the STT obtained by the N150 latencies overlapped that obtained by the P340/P400 latencies.


CONCLUSIONS
Our data suggest that our method appears appropriate and useful for practical clinical purposes, furnishing an additional tool for investigating the physiological function of small-fiber pathways.
Rossi
P
P
Istituto di Clinica delle Malattie Nervose e Mentali, Università degli Studi di Roma "La Sapienza", Rome, Italy.
Serrao
M
M
Amabile
G
G
Parisi
L
L
Pierelli
F
F
Pozzessere
G
G
D001921:Brain / Q000502:physiology*; D005071:Evoked Potentials / Q000502:physiology*; D006801:Humans; D007834:Lasers; D009431:Neural Conduction / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D012016:Reference Values; D013133:Spinothalamic Tracts / Q000502:physiology*