Posterior parietal cortex automatically encodes the location of salient stimuli.

@article{citeulike:105100, abstract = {We examined the responses of neurons in posterior parietal area 7a to salient stimuli appearing alone or within multiple-stimulus displays in monkeys trained only to maintain fixation. Discharges in a population of parietal neurons encoded the location of the salient stimulus, although the latter had no task significance for the monkey. Neuronal selectivity for the location of the salient stimulus depended solely on its intrinsic difference from the background elements in the array and not on the color of the stimulus per se. These results were similar to those reported in monkeys trained to actively locate a salient stimulus in a multiple-stimulus display. A lower percentage of neurons with significant selectivity for the salient stimulus was observed in the fixation-only animals. These neurons took longer for the selective responses to emerge and showed a lower power of discrimination. The findings suggest that the posterior parietal cortex automatically detects and encodes the location of salient stimuli even when they are unrelated to the behavioral task.}, address = {Zanvyl Krieger Mind/Brain Institute, Johns Hopkins University, Baltimore, Maryland 21218, USA. cconstan@wfubmc.edu}, author = {Constantinidis, C. and Steinmetz, M. A. }, citeulike-article-id = {105100}, comment = {* followup experiment to earlier study showing differential responses of PPC 7a neurons to the location of a salient (color different) target in a grid array * in this task monkeys were required only to fixate throughout cue presentation, suggesting an automatic encoding of stimulus salience * suggests that earlier result reflects bottom-up stimulus processing rather than top-down willful attention * one open question is the role of parietal areas in bottom-up attention processes, which are traditionally associated with ventral stream areas * NOTE: data shows a suppressive effect of multiple stimuli compared to a single stimulus presented in the RF}, doi = {10.1523/JNEUROSCI.3379-04.2005}, issn = {1529-2401}, journal = {J Neurosci}, keywords = {attention, bottomup, electrophysiology, monkey, normalization, \_note, posteriorparietal, salience}, month = {January}, number = {1}, pages = {233--238}, posted-at = {2006-11-11 18:11:17}, priority = {2}, title = {Posterior parietal cortex automatically encodes the location of salient stimuli.}, url = {http://dx.doi.org/10.1523/JNEUROSCI.3379-04.2005}, volume = {25}, year = {2005} }

TY - JOUR ID - citeulike:105100 L3 - citeulike-article-id:105100 TI - Posterior parietal cortex automatically encodes the location of salient stimuli. JF - J Neurosci VL - 25 IS - 1 SP - 233 EP - 238 AD - Zanvyl Krieger Mind/Brain Institute, Johns Hopkins University, Baltimore, Maryland 21218, USA. cconstan@wfubmc.edu SN - 1529-2401 N2 - We examined the responses of neurons in posterior parietal area 7a to salient stimuli appearing alone or within multiple-stimulus displays in monkeys trained only to maintain fixation. Discharges in a population of parietal neurons encoded the location of the salient stimulus, although the latter had no task significance for the monkey. Neuronal selectivity for the location of the salient stimulus depended solely on its intrinsic difference from the background elements in the array and not on the color of the stimulus per se. These results were similar to those reported in monkeys trained to actively locate a salient stimulus in a multiple-stimulus display. A lower percentage of neurons with significant selectivity for the salient stimulus was observed in the fixation-only animals. These neurons took longer for the selective responses to emerge and showed a lower power of discrimination. The findings suggest that the posterior parietal cortex automatically detects and encodes the location of salient stimuli even when they are unrelated to the behavioral task. KW - attention KW - bottomup KW - electrophysiology KW - monkey KW - normalization KW - _note KW - posteriorparietal KW - salience N1 - * followup experiment to earlier study showing differential responses of PPC 7a neurons to the location of a salient (color different) target in a grid array * in this task monkeys were required only to fixate throughout cue presentation, suggesting an automatic encoding of stimulus salience * suggests that earlier result reflects bottom-up stimulus processing rather than top-down willful attention * one open question is the role of parietal areas in bottom-up attention processes, which are traditionally associated with ventral stream areas * NOTE: data shows a suppressive effect of multiple stimuli compared to a single stimulus presented in the RF AU - Constantinidis, C AU - Steinmetz, MA PY - 2005/01/05/ UR - http://dx.doi.org/10.1523/JNEUROSCI.3379-04.2005 ER -