Restorative Neurology and Neuroscience - Volume 4, issue 4

Authors: Rose, F.D. | Johnson, D.A.

Article Type: Research Article

DOI: 10.3233/RNN-1992-4401

Citation: Restorative Neurology and Neuroscience, vol. 4, no. 4, pp. 241-244, 1992

Authors: Kerkhoff, G. | Münßinger, U. | Haaf, E. | Eberle-Strauss, G. | Stögerer, E.

Article Type: Research Article

Abstract: A systematic training procedure for patients with disturbed visual search was evaluated in 92 patients with postchiasmatic visual field disorders (VFD) and 30 VFD patients with additional leftsided visual neglect (VFD +). Visual fields and areas of visual search via saccadic eye movements in the scotomatous field (search field) were mapped perimetrically in all patients before and after training and after a follow-up interval (mean follow-up interval: 22 months). A significant increase of more than 20° of visual angle was found in visual search field in the scotomatous field during training. Search field remained stable at follow-up in both patient …groups. In contrast, only minor, though significant increases in visual field size were obtained during search field training in some patients. Multiple baseline designs in 5 patients revealed that search field enlargements were training dependent and not related to spontaneous recovery, adaptation to test procedures or measurement variability. VFD + Neglect patients needed some 25% more therapy sessions than VFD patients to achieve the same amount of increase in visual search field. Frequent head movements had a deleterious effect on training progress. It is concluded that the presented training procedure can lead to a significant and stable improvement in visual search within 15 to 25 training sessions and hence to a better compensation of visual deficits in daily living in most patients with VFD and/or visual neglect. Show more

Keywords: Brain damage, Hemianopia, Visual Neglect, Saccadic training, Visual field restitution, Baseline design

DOI: 10.3233/RNN-1992-4402

Citation: Restorative Neurology and Neuroscience, vol. 4, no. 4, pp. 245-254, 1992

Authors: Suarez, H. | Caffa, C. | Macadar, O.

Article Type: Research Article

Abstract: Vestibular habituation was studied in normal subjects and in patients with cerebellar disease using a stimulation paradigm proposed in this paper. Six caloric stimuli were repeated daily in the same ear during six days and electronystagmographic responses at the beginning and the end of that period were compared. The normal behaviour was a clear reduction of the response across time. Two groups of cerebellar patients were identified by their ability to recover from positional imbalance after treatment. Compensated patients responded to repeated caloric stimulation in the same way as normal subjects. Conversely, uncompensated patients increased their response after the stimulation …paradigm. The role played by the cerebellum in vestibular plasticity is discussed together with the observed correlation between vestibular habituation and the ability for postural recovery to occur. Show more

Keywords: Vestibular plasticity, Post caloric nystagmus

DOI: 10.3233/RNN-1992-4403

Citation: Restorative Neurology and Neuroscience, vol. 4, no. 4, pp. 255-259, 1992

Authors: Boer, Gerard J. | Griffioen, Henriëtte A. | Saeed, Peerooz

Article Type: Research Article

Abstract: A comparison was made between the survival of fetal suprachiasmatic nucleus (SCN) grafted either in tissue pieces or as tissue suspension. Donor tissue was obtained from day 15, 16 or 17 Wistar fetuses, and stereotaxically placed in the dorsal thalamus of the brain of vasopressin(VP)-deficient Brattleboro adult rats. One month post-grafting, the suspension grafts largely failed to show the immunocytochemical presence of VP- and vasoactive intestinal polypeptide(VIP)-producing SCN cells, but solid piece grafts did. In the suspension grafts only a few tiny clusters of surviving VP SCN neurons were seen and hardly any VIP cells. This suggests that intrinsic contacts …are necessary for SCN cells to survive and/or to express their genotype. Efferent VP fiber growth was observed to run from the tissue piece derived SCN grafts towards the periventricular area of the thalamus, a nearby SCN projection area. However, the number of VP efferents was very limited and not consistently present. Surprisingly, magnocellular VP neurons, also present in the fetal SCN grafts, showed an opposite survival pattern. Several of such cells were seen in day 15 suspension grafts, whereas hardly any were found in day 15 tissue piece grafts. These results indicate that the type of graft preparation might be important when survival of particular cells is desired. Show more

Keywords: Suprachiasmatic nucleus, Transplantation, Vasopressin, Vasoactive intestinal polypeptide, Magnocellular neuron

DOI: 10.3233/RNN-1992-4404

Citation: Restorative Neurology and Neuroscience, vol. 4, no. 4, pp. 261-269, 1992

Authors: Levin, Harvey S. | Goldstein, Felicia C. | Crofford, Marsha J. | Eisenberg, Howard M. | Guinto Jr., Faustino C.

Article Type: Research Article

Abstract: Serial neuropsychological findings were obtained in a case of infantile right parietal injury who was studied over a 13 year follow-up period. Magnetic resonance imaging at age 13 years documented extensive injury to the right hemisphere, particularly the parietal region. Serial examinations at age 7 and 13 years showed intact visual attention, normal expression and processing of affect and variable visuospatial abilities. However, intellectual development was generally depressed. Implications of these findings for recovery from early brain injury are discussed.

Keywords: Right hemisphere, Brain injury, Visuospatial function

DOI: 10.3233/RNN-1992-4405

Citation: Restorative Neurology and Neuroscience, vol. 4, no. 4, pp. 271-277, 1992

Authors: Bragin, A.G. | Vinogradova, O.S. | Stafekhina, V.S.

Article Type: Short Communication

Abstract: The histological and electrophysiological properties of embryonic neocortical grafts transplanted into the barrel field of adult rats were compared between the side receiving normal vibrissae input vs. chronic deprivation of input produced by clipping of the recipients vibrissae. Each animal received ablation of the neocortex and transplantation of neocortical tissue bilaterally. Vibrissae were clipped unilaterally immediately after surgery and were trimmed for up to 4 months. Significant differences were found between volume of the grafts as well as the number of grafts showing contact with the wall of the lesion cavity, indicating that the tissue growth was directly influenced by …sensory deprivation. Decrements in functional integration with the host brain measured electrophysiologically were also observed. Show more

Keywords: Transplantation, Neocortex, Barrel field, Sensory deprivation

DOI: 10.3233/RNN-1992-4406

Citation: Restorative Neurology and Neuroscience, vol. 4, no. 4, pp. 279-283, 1992

Authors: Zrull, Mark C. | Wessinger, Terry M. | Coleman, James R.

Article Type: Research Article

Abstract: Long-Evans rats with unilateral lesions of the dorsal inferior colliculus (IC) received transplants of fetal tectal tissue to determine functional efficacy. Acoustic stimulation increases metabolic activity in both graft and host tissues relative to spontaneous activity in these regions. During periods of quiescence, graft tissue shows basal metabolic activity similar to that found in host IC. Coupled with previous anatomical findings, the results suggest that tectal grafts not only possess a neural structure resembling normal adult IC, but also contain cellular constituents which are responsive to sound. Given the apparent system-appropriate function of implanted fetal tectum, the graft tissue may …be able to have a restorative effect within the damaged central auditory pathway. Show more

Keywords: Inferior colliculus, Metabolic mapping, 2-Deoxyglucose

DOI: 10.3233/RNN-1992-4407

Citation: Restorative Neurology and Neuroscience, vol. 4, no. 4, pp. 285-289, 1992

Article Type: Research Article

DOI: 10.3233/RNN-1992-4408

Citation: Restorative Neurology and Neuroscience, vol. 4, no. 4, pp. 291-300, 1992