Biofeedback of Very Early Potentials from the Brain Stem

Operant conditioning of evoked potentials (EPs) has been demonstrated both in animal preparations (Dowman, Rosenfeld, & Heinricher, in press; Fox & Rudell, 1968, 1970; Heinricher, Rosenfeld, & Dowman, 1981; Roger & Galand, 1980; Rosenfeld & Fox, 1971 ; Rosenfeld & Hetzler, 1973; Rosenfeld, Hetzler, & Kosnik, 1974; Rosenfeld & Owen, 1972; and Rosenfeld, Rudell, & Fox, 1969), and in man (Roger & Galand, 1981 ; Rosenfeld, Rudell, & Fox, 1969). Roger (Roger & Galand, 1980; Roger & Galand, 1981; and Roger, Sanfourche, & Galand, 1979) has shown that discrete segments of the visual EP can be operantly conditioned. Moreover, both early and late segments are conditionable. However, in man, late components are more readily modifiable through conditioning than are early components. Conditioning of short-latency, subcortical structures has been demonstrated in animal preparations. For example, trigeminal nuclear EPs with peak latencies as brief as 8–20 msec have been conditioned (Heinricher, Rosenfeld, & Dowman, 1981). In man, Roger and Galand (1981) conditioned visual EP components occurring as early as 75 msec. Rosenfeld, Rudell, and Fox (1969) conditioned long-latency auditory EP components around 200 msec.