Academic Journal
Neuronal response sensitivity to bidirectional off-vertical axis rotations: A dimension of imbalance in the bilateral vestibular nuclei of cats after unilateral labyrinthectomy
| العنوان: | Neuronal response sensitivity to bidirectional off-vertical axis rotations: A dimension of imbalance in the bilateral vestibular nuclei of cats after unilateral labyrinthectomy |
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| المؤلفون: | Shum, DKY, Lai, CH, Chan, YS |
| بيانات النشر: | //www.elsevier.com/locate/neuroscience Netherlands |
| سنة النشر: | 1999 |
| المجموعة: | University of Hong Kong: HKU Scholars Hub |
| مصطلحات موضوعية: | Bidirectional response sensitivity, Off-vertical axis rotation, Otolith, Vestibular nuclear neuron, Hemilabyrinthectomy, Neurons - physiology, Vestibular Nuclei - physiology, Animals, Cats, Ear, Inner - physiology, Electrophysiology - methods, Functional Laterality, Motor Activity - physiology, Rotation |
| الوصف: | In decerebrate cats after acute hemilabyrinthectomy, the response sensitivity of extracellularly recorded vestibular nuclear neurons on the lesioned and labyrinth-intact sides were examined quantitatively during constant velocity off-vertical axis rotations with an aim to elucidate the functional contribution of otolithic inputs to the ipsilateral and contralateral vestibular nuclei. The bidirectional response sensitivity, δ, was determined as the ratio of the gain during clockwise to that during counterclockwise rotations. A continuum of response sensitivity was identified: one-dimensional neurons showed symmetrically bidirectional response patterns, while two-dimensional neurons showed asymmetrically bidirectional patterns that in some cases approached unidirectional patterns with change in velocity. The proportion of two-dimensional neurons was significantly increased after acute hemilabyrinthectomy. Two-dimensional neurons that responded only to one direction of rotation in at least one of the velocities tested were described as unidirectional neurons. This unidirectional response pattern was observed in one-third of the entire neuronal population studied, but not in cats with both labyrinths intact, thus suggesting that such prominent broadly tuned responses are normally masked by converging otolithic inputs from the contralateral side. These neurons were found in higher proportion on the lesioned side than on the labyrinth-intact side. Among the 70% of unidirectional neurons that exhibited bidirectional response at some velocities and unidirectional response at others, prominent shifts in δ values (i.e. between 0/∞ and finite values) with velocity can be computed for each neuron. The shifts in δ values correlated with large shifts in the response dynamics and spatial orientation as the response pattern changed with velocity. The response orientations of the unidirectional neurons pointed in all directions on the horizontal plane. When all the two-dimensional neurons (i.e. both the unidirectionally and ... |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | English |
| تدمد: | 0306-4522 |
| Relation: | Neuroscience; http://www.scopus.com/mlt/select.url?eid=2-s2.0-0032846190&selection=ref&src=s&origin=recordpage; Neuroscience, 1999, v. 94 n. 3, p. 831-843; 843; 53665; WOS:000083250900016; http://library.hku.hk:4550/resserv?sid=HKU:IR&issn=0306-4522&volume=94&spage=831&epage=843&date=1999&atitle=Neuronal+response+sensitivity+to+bidirectional+off-vertical+axis+rotations:+A+dimension+of+imbalance+in+the+bilateral+vestibular+nuclei+of+cats+after+unilateral+labyrinthectomy; eid_2-s2.0-0032846190; 831; http://hdl.handle.net/10722/68221; 94 |
| DOI: | 10.1016/S0306-4522(99)00374-7 |
| الاتاحة: | https://doi.org/10.1016/S0306-4522(99)00374-7 http://library.hku.hk:4550/resserv?sid=HKU:IR&issn=0306-4522&volume=94&spage=831&epage=843&date=1999&atitle=Neuronal+response+sensitivity+to+bidirectional+off-vertical+axis+rotations:+A+dimension+of+imbalance+in+the+bilateral+vestibular+nuclei+of+cats+after+unilateral+labyrinthectomy http://hdl.handle.net/10722/68221 |
| Rights: | Neuroscience. Copyright © Elsevier BV. |
| رقم الانضمام: | edsbas.5F09B9BE |
| قاعدة البيانات: | BASE |
| تدمد: | 03064522 |
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| DOI: | 10.1016/S0306-4522(99)00374-7 |