Blink reflexes elicited by electrical stimulation of the supraorbital nerves, by monoaurally presented 1 kHz sine wave bursts of 20-ms duration, and by flashes of light presented monocularly were investigated in 32 healthy controls. Absolute latencies of the individual components and side differences were measured. An outline of possible anatomical pathways which might be involved in the transmission of these reflexes is given.
Spike activity of single optic tract fibres and lateral geniculate cells of the lightly anaesthetized immobilized cat were recorded in response to short, small (local) test flashes into the receptive field center before, during and after rapid displacements of a remote, large (global) pattern. 2. The majority of retinal and geniculate neurons failed to produce algebraic summation of the excitatory shift-effect and an excitatory test response. 3. For many cells outside lamina A and A1 of the dorsal lateral geniculate body the test response was smaller than the control even though two excitatory responses were combined. 4. The resonses to displacements of a steady, local spot are weakly affected by simultaneous displacements of a global pattern if the local responses are strong; but if the latter are weak the global shift-effect dominates the response to a displacement of the total pattern. 5. Saccadic suppression may be explained by retinal and geniculate neurons functioning in two modes of local or global responses, both of which cannot be transmitted properly at the same time.
Pattern reversal visual evoked potentials (VEP), blink reflexes, auditory brainstem evoked potentials (ABEP), spinal and scalp recorded somatosensory evoked potentials (SSEP), and nystagmographic records were investigated in 55 patients with multiple sclerosis (MS), who were separated in different categories of probability according to the clinical history, symptoms, and signs. The combined use of different electrophysiological methods forms a sensitive battery for investigating clinically uncertain cases of MS. It was stressed that care should be taken in the interpretation of the electrophysiological findings, since a single lesion in the central nervous system, particularly in the brainstem, may affect different functional systems simultaneously and therefore mimic a disseminated disease.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.