Chester Osborn

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The responses of Golgi tendon organs to single motor unit contractions were studied to determine whether receptors located in the same muscle region respond to a common set of motor units. In each of five experiments we isolated a large fraction (25-65%) of the motor units of the cat tibialis posterior muscle and determined to which of the units each of(More)
1. We examined the functional organization of the dorsal spinocerebellar tract (DSCT) and found that it is similar to that of a parallel distributed network having widespread connectivity among parallel elements. The prevailing view is that the DSCT provides receptor-specific information to the cerebellum regarding muscle and cutaneous inputs from the(More)
The selective bradykinin analogue, RMP-7, transiently increases the permeability of the blood brain barrier and the delivery of hydrophilic agents into brain tumours. In 87 recurrent glioma patients (WHO Grade III/IV, median age 46, Karnofsky 70%) clinical and Magnetic Resonance Imaging (MRI) responses to i.v. cycles (q 28 days) of RMP-7 (300 ng/kg given as(More)
1. Impulse activity of 264 units of the dorsal spinocerebellar tract (DSCT) was recorded during random contraction or stretch in hindlimb muscles. Contractions were evoked in either the isolated gastrocnemius-soleus (GS) muscles or the intact limb during crossed-extensor reflexes; stretches were applied to the isolated GS. 2. The time course of poststimulus(More)
1. Impulse activity of single units belonging to the dorsal spinocerebella tract (DSCT) was recorded in response to electrical stimulation of peripheral muscle nerves at group I intensities. The responses for 187 units were determined using a spike train analysis technique that facilitates the comparison of poststimulus response time course across units(More)
Activity of DSCT units was cross-correlated with stimuli evoking gastrocnemius-soleus muscle stretch or contraction in order to investigate the muscle receptor input to DSCT. The most potent stimulus was generally muscle contraction, and the most common response one of inhibition. The similarity in response of many units to stretch, contraction and nerve(More)
Monosynaptic connections from sensory receptors to the dorsal spinocerebellar tract are believed to have a significant role in the transmission of sensory information to the cerebellum. However, predominant polysynaptic connections with highly convergent afferent input suggest a functional organization based on integrated sensory representations. We(More)
We investigated the extent of the distribution of polysynaptic connections to the dorsal spinocerebellar tract (DSCT). Recording from a randomly selected population of DSCT units, we found that over 60% responded to maximal stimulation of group I afferent fibers in the gastrocnemius-soleus muscle nerve. Most of the responses had a time course or latency(More)
INTRODUCTION In recurrent malignant glioma, early imaging response to two courses of chemotherapy is generally considered to be predictive of good survival. We studied the relationships between initial tumour volume and speed of imaging response to chemotherapy in malignant glioma. METHODS In 43 chemotherapy naïve patients, 26 glioblastoma multiforme(More)
We present a novel method for measuring changes in the timing of spikes evoked by a stimulus in single neurons. The result provides an unambiguous separation of the stimulus effect from effects due to intrinsic spike train patterns. This separation facilitates the comparison of responses in different neurons. The analysis is based only on the spike train(More)