Activity in the human superior colliculus relating to endogenous saccade preparation and execution
| Autor: | Michele Furlan, Robin Walker, Andrew Smith |
|---|---|
| Rok vydání: | 2015 |
| Předmět: |
Male
Superior Colliculi genetic structures Physiology Neuropsychological Tests Biology Brain mapping Functional Laterality Foveal Saccades Humans Eye Movement Measurements Brain Mapping General Neuroscience Superior colliculus Eye movement Anticipation Psychological Magnetic Resonance Imaging Saccadic masking Oxygen Inhibition Psychological Higher Neural Functions and Behavior Cerebrovascular Circulation Saccade Fixation (visual) Female Neuroscience Photic Stimulation Psychomotor Performance |
| Zdroj: | Journal of Neurophysiology. 114:1048-1058 |
| ISSN: | 1522-1598 0022-3077 |
| DOI: | 10.1152/jn.00825.2014 |
| Popis: | In recent years a small number of studies have applied functional imaging techniques to investigate visual responses in the human superior colliculus (SC), but few have investigated its oculomotor functions. Here, in two experiments, we examined activity associated with endogenous saccade preparation. We used 3-T fMRI to record the hemodynamic activity in the SC while participants were either preparing or executing saccadic eye movements. Our results showed that not only executing a saccade (as previously shown) but also preparing a saccade produced an increase in the SC hemodynamic activity. The saccade-related activity was observed in the contralateral and to a lesser extent the ipsilateral SC. A second experiment further examined the contralateral mapping of saccade-related activity with a larger range of saccade amplitudes. Increased activity was again observed in both the contralateral and ipsilateral SC that was evident for large as well as small saccades. This suggests that the ipsilateral component of the increase in BOLD is not due simply to small-amplitude saccades producing bilateral activity in the foveal fixation zone. These studies provide the first evidence of presaccadic preparatory activity in the human SC and reveal that fMRI can detect activity consistent with that of buildup neurons found in the deeper layers of the SC in studies of nonhuman primates. |
| Databáze: | OpenAIRE |
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