Temporal sensitivity in a hemianopic visual field can be improved by long-term training using flicker stimulation

التفاصيل البيبلوغرافية
العنوان: Temporal sensitivity in a hemianopic visual field can be improved by long-term training using flicker stimulation
المؤلفون: Simo Vanni, Risto Näsänen, Lea Hyvärinen, Antti Raninen
المصدر: Journal of Neurology, Neurosurgery & Psychiatry. 78:66-73
بيانات النشر: BMJ, 2007.
سنة النشر: 2007
مصطلحات موضوعية: Paper, Male, medicine.medical_specialty, Time Factors, Eye Movements, genetic structures, Flicker fusion threshold, Audiology, Flicker stimulation, 050105 experimental psychology, Flicker Fusion, 03 medical and health sciences, 0302 clinical medicine, medicine, Humans, 0501 psychology and cognitive sciences, Hemianopsia, Cerebral Cortex, Communication, business.industry, Flicker, 05 social sciences, Training (meteorology), Eye movement, Cerebral Infarction, Middle Aged, medicine.disease, Magnetic Resonance Imaging, eye diseases, Visual field, Psychiatry and Mental health, Surgery, Neurology (clinical), Psychology, business, Sensitivity (electronics), 030217 neurology & neurosurgery
الوصف: Background: Blindness of a visual half-field (hemianopia) is a common symptom after postchiasmatic cerebral lesions. Although hemianopia severely limits activities of daily life, current clinical practice comprises no training of visual functions in the blind hemifield. Objective: To find out whether flicker sensitivity in the blind hemifield can be improved with intensive training, and whether training with flicker stimulation can evoke changes in cortical responsiveness. Methods: Two men with homonymous hemianopia participated in the experiments. They trained with flicker stimuli at 30° or with flickering letters at 10° eccentricity twice a week for a year, and continued training with more peripheral stimuli thereafter. Neuromagnetic responses were registered at 1–2-month intervals, and the Goldmann perimetry was recorded before, during and after training. Results: Flicker sensitivity in the blind hemifield improved to the level of the intact hemifield within 30° eccentricity in one participant and 20° eccentricity in the other. Flickering letters were recognised equally at 10° eccentricity in the blind and intact hemifields. Improvement spread from the stimulated horizontal meridian to the whole hemianopic field within 30°. Before training, neuromagnetic recordings showed no signal above the noise level in the hemianopic side. During training, evoked fields emerged in both participants. No changes were found in the Goldmann perimetry. Discussion: Results show that sensitivity to flicker could be fully restored in the stimulated region, that improvement in sensitivity spreads to the surrounding neuronal networks, and that, during training, accompanying changes occurred in the neuromagnetic fields.
تدمد: 0022-3050
DOI: 10.1136/jnnp.2006.099366
URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::49c869d633989048a3898f064bf56d4f
https://doi.org/10.1136/jnnp.2006.099366
Rights: OPEN
رقم الانضمام: edsair.doi.dedup.....49c869d633989048a3898f064bf56d4f
قاعدة البيانات: OpenAIRE
الوصف
تدمد:00223050
DOI:10.1136/jnnp.2006.099366