Traveling waves of neuronal oscillations have been observed in many cortical regions, including the motor and sensory cortex. Such waves are often modulated in a task-dependent fashion although their precise functional role remains a matter of debate. Here we conjecture that the cortex can utilize the direction and wavelength of traveling waves to encode information. We present a novel neural m...

The brainstem is said to be the generator of pathological startle responses due to reticular reflex myoclonus or hyperekplexia. A patient with facial weakness, nystagmus, and pyramidal tract signs had generalised reflex spasms in response to auditory, visual and tactile stimuli which clinically and neurophysiologically resembled hyperekplexia. The case is unusual because as well as hyperekplexi...

Currently the problem of the existence of primary lateral sclerosis as a distinct clinical entity is not a mat te r of much controversy. I t seems generally accepted that what was once regarded as a disease process char­ acterized by selective degeneration of the pyramidal tracts is usually, if not always, but one manifestation of a number of we l l defined diseases, such as amyotrophic lateral...

Clinical and neurophysiological findings in twenty patients intoxicated with tri-cresyl phosphate following consumption of contaminated gingili oil are reported. Marked distal axonopathy, high incidence of pyramidal tract dysfunction and minimal sensory abnormalities were the cardinal features. Despite pronounced motor weakness in the early stages, the patients showed remarkable improvement dur...

Determining how long-range synaptic inputs engage pyramidal neurons in primary motor cortex (M1) is important for understanding circuit mechanisms involved in regulating movement. We used channelrhodopsin-2-assisted circuit mapping to characterize the long-range excitatory synaptic connections made by multiple cortical and thalamic areas onto pyramidal neurons in mouse vibrissal motor cortex (v...

Two siblings are reported who developed classical signs and symptoms of Parkinsonism in the first decade of life. In addition, they had evidence of cortical spinal tract disease, thus putting them in the category of Davison's pallido-pyramidal syndrome. Both deteriorated to the point of a non-productive existence until the institution of levodopa treatment, at the ages of 18 and 20 years. The r...

We report a 16-year-old man with disorders of tetrahydrobiopterin metabolism due to dihydropteridine reductase (DHPR) deficiency. He revealed moderate mental retardation, parkinsonism, and spastic paralysis with levodopa and 5-hydroxytryptophan (5-HTP) supplementation from the age of 2 months. Brain MRI showed high intensity areas in bilateral frontal and posterior deep white matter on fluid-at...

Introduction. Leukoencephalopathy with brain stem and spinal cord involvement and lactate elevation (LBSL) is an inherited white matter disorder first recognized in 2003 by its distinct pattern of MRI abnormalities, including involvement of cerebral white matter, pyramidal and sensory tracts over their entire extent (including the spinal cord), and specific brain stem structures [1]. The diseas...

Motor evoked potentials and central motor conduction time (CMCT) were examined from both upper and lower limbs in patients with normal pressure hydrocephalus to find a predictor for the success of shunting procedures. The hypotheses that walking disturbances are due to pyramidal tract compression as well as the possibility that the upper limbs are affected subclinically in these patients were a...

The mammalian striatum receives its main excitatory input from the two types of cortical pyramidal neurons of layer 5 of the cerebral cortex - those with only intratelencephalic connections (IT-type) and those sending their main axon to the brainstem via the pyramidal tract (PT-type). These two neurons types are present in layer 5 of all cortical regions, and thus they appear to project togethe...