1/5. Subcortical brain mechanisms in speech and language.This paper reviews current research and contemporary theories of subcortical participation in the motor control of speech production and language processing. As a necessary precursor to the discussion of the functional roles of the basal ganglia and thalamus, the neuroanatomy of the basal ganglial-thalamocortical circuitry is described. Contemporary models of hypokinetic and hyperkinetic movement disorders based on recent neuroanatomical descriptions of the multi-segmented circuits that characterise basal ganglion anatomy are described. Reported effects of surgically induced lesions in the globus pallidus and thalamus on speech production are reviewed. In addition, contemporary models proposed to explain the possible contribution of various subcortical structures to language processing are described and discussed in the context of evidence gained from observation of the effects of circumscribed surgically induced lesions in the basal ganglia and thalamus on language function. The potential of studies based on examination of the speech/language outcomes of patients undergoing pallidotomy and thalamotomy to further inform the debate relating to the role of subcortical structures in speech motor control and language processing is highlighted.- - - - - - - - - - ranking = 1keywords = basal ganglion, ganglion (Clic here for more details about this article) |
2/5. Neuronal intranuclear inclusion disease. Clinical ophthalmological features and ophthalmic pathology.Monozygotic twin sisters were afflicted by a chronic progressive neurological disease characterized by slurred speech, nystagmus and oculogyral spasms as well as further extrapyramidal and lower motor neuron abnormalities. At autopsy severe loss of nigral and craniospinal motor neurons was noted. In the nuclei of most nerve cell types of the central and peripheral nervous system, roundish inclusion bodies of 3 to 10 microns in diameter were found. Ocular pathology revealed the presence of identical inclusion bodies in the ganglion cells and ganglion cell loss in the posterior retina. Retinal astrocytosis and loss of myelinated axons of the optic nerve were interpreted as reactive features. No inclusions were found in the retinal pigment epithelium. Careful neuro-ophthalmological studies of the first-degree relatives revealed low b-wave of the ERG with other slight aberrations. These were assumed to represent either a carrier or a subclinical state of this presumably inherited disorder.- - - - - - - - - - ranking = 0.57822826052722keywords = ganglion (Clic here for more details about this article) |
3/5. Fahr's disease. An otolaryngologic perspective.An idiopathic basal ganglion calcification occurring in a 35-year-old man was first observed as a speech deficit. The literature is reviewed, the condition of patients with this disease is evaluated, and a prognosis is given. To our knowledge, the prolongation of visual-evoked potentials by this abnormality is reported herein for the first time.- - - - - - - - - - ranking = 1keywords = basal ganglion, ganglion (Clic here for more details about this article) |
4/5. Clinical correlates of sudden auditory-vestibular loss in a cochlear implant patient.The precise electrophysiologic mechanism for sudden sensorineural auditory-vestibular loss has yet to be defined. No human models exist for this idiopathic phenomenon. A 67-year-old cochlear implant (CI) patient experienced what could be termed a "typical" acute sudden auditory-vestibular loss. Vestibular and CI electrical psychophysical changes were monitored over a 22-month period. Once the acute vestibular problems diminished, CI electrical parameters returned to near pre-episode levels. Some improvement occurred in rotational chair phase lag and asymmetry. While improving, platform posturography continued to show difficulty performing sensory organization tests V and VI. These clinical findings may imply that ganglion cell and neuronal population are responsible for the auditory findings in sudden auditory-vestibular loss. Secondly, a CI patient may serve as an ideal human model for further study of this phenomenon, should it occur.- - - - - - - - - - ranking = 0.28911413026361keywords = ganglion (Clic here for more details about this article) |
5/5. High-frequency stimulation of the globus pallidus internalis in Parkinson's disease: a study of seven cases.The effectiveness of ventroposterolateral pallidotomy in the treatment of akinesia and rigidity is not a new discovery and agrees with recent investigations into the pathogenesis of Parkinson's disease, which highlight the role played by the unbridled activity of the subthalamic nucleus (STN) and the consequent overactivity of the globus pallidus internalis (GPi). Because high-frequency stimulation can reversibly incapacitate a nerve structure, we applied stimulation to the same target. Seven patients suffering from severe Parkinson's disease (Stages III-V on the Hoehn and Yahr scale) and, particularly, bradykinesia, rigidity, and levodopa-induced dyskinesias underwent unilateral electrode implantation in the posteroventral GPi. Follow-up evaluation using the regular Unified Parkinson's disease Rating Scale has been conducted for 1 year in all seven patients, 2 years in five of them, and 3 years in one. In all cases high-frequency stimulation has alleviated akinesia and rigidity and has generally improved gait and speech disturbances. In some cases tremor was attenuated. In a similar manner, the authors observed a marked diminution in levodopa-induced dyskinesias. This could be an excellent primary therapy for younger patients exhibiting severe bradykinesia, rigidity, and levodopa-induced dyskinesias, which would allow therapists to keep ventroposterolateral pallidotomy in reserve as a second weapon.- - - - - - - - - - ranking = 0.015363337614587keywords = nucleus (Clic here for more details about this article) |