Neuronal activity in the lateral intraparietal area and spatial attention.

@article{citeulike:90449, abstract = {Although the parietal cortex has been implicated in the neural processes underlying visual attention, the nature of its contribution is not well understood. We tracked attention in the monkey and correlated the activity of neurons in the lateral intraparietal area (LIP) with the monkey's attentional performance. The ensemble activity in LIP across the entire visual field describes the spatial and temporal dynamics of a monkey's attention. Activity subtending a single location in the visual field describes the attentional priority at that area but does not predict that the monkey will actually attend to or make an eye movement to that location.}, address = {Laboratory of Sensorimotor Research, National Eye Institute, Bethesda, MD 20892, USA. jwb2003@columbia.edu}, author = {Bisley, J. W. and Goldberg, M. E. }, citeulike-article-id = {90449}, comment = {* neurophysiological study of the relationship between LIP neuron activity and behaviorally-defined spatial attention * the authors use enhanced contrast sensitivity (decreased psychometric threshold) as an index of alloted spatial attention (as opposed to reaction time) * task consisted of a single spatial target, and the monkey deciding whether to make a saccade to the remembered location or hold fixation based on a subsequent GO/NOGO probe stimulus * contrast variation in the probe demonstrates enhanced sensitivity (decreased threshold) when the target appeared at the same location as the probe * a flashed task-irrelevant distractor was presented during the delay (500 ms after target) at either the saccade goal or opposite * at short distractor-probe stimulus onset asynchronies (200 ms), contrast sensitivity is enhanced at the distractor instead of the target site; by 700 ms the target site regains the attentional advantage * the response of LIP neurons in two different trials, when the target is in the RF compared to when the distractor is in the RF, can be conceptualized as the response of two different populations with opposite RFs in the same trial * behavioral attentional advantage is determined by which normalized population LIP activity is greater: at any given time in the trial, enhanced contrast sensitivity was located at the site where the corresponding LIP population had higher activity * the authors emphasize that attentional advantage appears to be ''binary'': there was no clear relationship between absolute LIP activity and the level of attentional advantage (at least as measured by contrast threshold) * distractor LIP activity 100 ms before probe appearance was higher in error than correct trials, and conversely target LIP activity was greater in correct than error trials; this suggests that the ratio of target/distractor activity predicts monkey performance * initial LIP responses to probe appearance within the RF were similar for GO to RF, GO opposite to RF, and NOGO conditions; however, while GO opposite RF responses decreased quickly and to a lower level than GO to RF responses, NOGO responses fell much more slowly (but eventually dropping below GO to RF) * the authors suggest that LIP (and related areas) can function as a salience map that provides the bias for biased competition models (e.g. 'Desimone and Duncan 1995':http://www.citeulike.org/user/klouie/article/773639 ) * note: this work centers primarily on the effect of bottom-up (exogenous) attention, driven by the distractor onset, on preexisting top-down (endogenous) attention, controlled by saccade planning }, doi = {10.1126/science.1077395}, issn = {1095-9203}, journal = {Science}, keywords = {attention, lip, monkey, neurophysiology, \_note}, month = {January}, number = {5603}, pages = {81--86}, posted-at = {2005-02-08 22:23:59}, priority = {2}, title = {Neuronal activity in the lateral intraparietal area and spatial attention.}, url = {http://dx.doi.org/10.1126/science.1077395}, volume = {299}, year = {2003} }

TY - JOUR ID - citeulike:90449 L3 - citeulike-article-id:90449 TI - Neuronal activity in the lateral intraparietal area and spatial attention. JF - Science VL - 299 IS - 5603 SP - 81 EP - 86 AD - Laboratory of Sensorimotor Research, National Eye Institute, Bethesda, MD 20892, USA. jwb2003@columbia.edu SN - 1095-9203 N2 - Although the parietal cortex has been implicated in the neural processes underlying visual attention, the nature of its contribution is not well understood. We tracked attention in the monkey and correlated the activity of neurons in the lateral intraparietal area (LIP) with the monkey's attentional performance. The ensemble activity in LIP across the entire visual field describes the spatial and temporal dynamics of a monkey's attention. Activity subtending a single location in the visual field describes the attentional priority at that area but does not predict that the monkey will actually attend to or make an eye movement to that location. KW - attention KW - lip KW - monkey KW - neurophysiology KW - _note N1 - * neurophysiological study of the relationship between LIP neuron activity and behaviorally-defined spatial attention * the authors use enhanced contrast sensitivity (decreased psychometric threshold) as an index of alloted spatial attention (as opposed to reaction time) * task consisted of a single spatial target, and the monkey deciding whether to make a saccade to the remembered location or hold fixation based on a subsequent GO/NOGO probe stimulus * contrast variation in the probe demonstrates enhanced sensitivity (decreased threshold) when the target appeared at the same location as the probe * a flashed task-irrelevant distractor was presented during the delay (500 ms after target) at either the saccade goal or opposite * at short distractor-probe stimulus onset asynchronies (200 ms), contrast sensitivity is enhanced at the distractor instead of the target site; by 700 ms the target site regains the attentional advantage * the response of LIP neurons in two different trials, when the target is in the RF compared to when the distractor is in the RF, can be conceptualized as the response of two different populations with opposite RFs in the same trial * behavioral attentional advantage is determined by which normalized population LIP activity is greater: at any given time in the trial, enhanced contrast sensitivity was located at the site where the corresponding LIP population had higher activity * the authors emphasize that attentional advantage appears to be ''binary'': there was no clear relationship between absolute LIP activity and the level of attentional advantage (at least as measured by contrast threshold) * distractor LIP activity 100 ms before probe appearance was higher in error than correct trials, and conversely target LIP activity was greater in correct than error trials; this suggests that the ratio of target/distractor activity predicts monkey performance * initial LIP responses to probe appearance within the RF were similar for GO to RF, GO opposite to RF, and NOGO conditions; however, while GO opposite RF responses decreased quickly and to a lower level than GO to RF responses, NOGO responses fell much more slowly (but eventually dropping below GO to RF) * the authors suggest that LIP (and related areas) can function as a salience map that provides the bias for biased competition models (e.g. 'Desimone and Duncan 1995':http://www.citeulike.org/user/klouie/article/773639 ) * note: this work centers primarily on the effect of bottom-up (exogenous) attention, driven by the distractor onset, on preexisting top-down (endogenous) attention, controlled by saccade planning AU - Bisley, JW AU - Goldberg, ME PY - 2003/01/03/ UR - http://dx.doi.org/10.1126/science.1077395 ER -