To define alterations of neuronal connectivity that occur during motor neuron degeneration, we characterized the function and structure of spinal circuitry in spinal muscular atrophy (SMA) model mice. SMA motor neurons show reduced proprioceptive reflexes that correlate with decreased number and function of synapses on motor neuron somata and proximal dendrites. These abnormalities occur at an ...

Two related cases of a proximal muscular dystrophy are described with the full postmortem findings in one of them. The strong family history is recorded. The condition was clinically predominant in the proximal limb muscles and showed an autosomal dominant type of inheritance with complete penetrance.

PURPOSE Insulin-like growth factor 1 (IGF1) and cardiotrophin 1 (CT1) are known to increase the strength of extraocular muscles in adult and embryonic animals, but no information is available for the early postnatal period, when strabismus treatment in humans is most urgent. Here the authors sought to determine whether these trophic factors strengthen juvenile maturing extraocular muscles and g...

Motor units within human muscles usually exhibit a significant degree of short-term synchronization. Such coincident spiking typically has been attributed to last-order projections that provide common synaptic input across motor neurons. The extent of branched input arising directly from cortical neurons has often been suggested as a critical factor determining the magnitude of short-term synch...

[Purpose] The purpose of this study was to measure the muscle activities of the trunk muscles and upper limb muscles during maximum isometric contraction when temporomandibular joint alignment was achieved with a mandibular orthopedic repositioning appliance in order provide basic data on the effects of mandibular orthopedic repositioning appliance on the entire body. [Subjects] The present stu...

1) Studies were made of the accessory abducens nucleus and its relationship to the extraocular muscles besides the retractor bulbi muscles in the rat. 2) All the extraocular muscles had nerve fiber connections from the accessory abducens nucleus besides the retractor bulbi muscles. 3) The relationship between the accessory facial nucleus and accessory abducens nucleus was investigated. The acce...

The electromyographic (EMG) reflex response evoked in muscles stretched by imposed angular joint displacement has previously been studied in a variety of muscles and species. In most muscles studied, the EMG response consists of an initial burst of activity at latencies comparable to tendon tap responses followed by one or more bursts of EMG activity occurring at latencies less than somatosenso...

STUDY OBJECTIVES The aim of our study was to determine which muscle or combination of muscles (either axial or limb muscles, lower or upper limb muscles, or proximal or distal limb muscles) provides the highest rates of rapid eye movement (REM) sleep phasic electromyographic (EMG) activity seen in patients with REM sleep behavior disorder (RBD). SETTING Two university hospital sleep disorders...

OBJECTIVE This study examined the effect of commonly used long and short styles of commercially produced wrist extension orthoses on the activity of the proximal muscles of the shoulder and elbow and on wrist flexor and extensor muscle activity. METHOD While 17 women between 22 and 40 years of age (M = 26.6) performed a specified movement wearing each of the two styles of orthosis and without...

Brachial amyotrophic diplegia (BAD) is a subtype of sporadic lower motor neuron disease (LMND) presenting with adult onset, mainly in men, and remaining largely restricted to proximal arm and shoulder girdle muscles without involvement of the lower limbs or appearance of pyramidal signs. 1,2 Mutations in the cop-per/zinc superoxide dismutase (SOD1) gene have been described in familial cases of ...