P-300 event-related potentials were recorded in 12 patients with chron
ic law back pain following epidural methylprednisolone administration.
The values of absolute peak latencies and amplitudes of P-300 were re
corded before (baseline) and on the 5th and 10th days following epidur
al injection. Intensity of pain was also recorded using a 10-cm visual
analogue scale score. The absolute peak latency of P-300 significantl
y decreased on the 5th and 10th days following epidural methylpredniso
lone (p<0.001) when compared with baseline value. Visual analogue scor
es also decreased significantly (p < 0.001) after the 5th and 10th day
s of epidural methylprednisolone. These observations suggest that foll
owing epidural methylprednisolone administration in chronic low back p
ain patients, significant improvement in cognitive functions and pain
relief go hand in hand.