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Orienting attention to semantic categories.

Cristescu TC, Devlin JT, Nobre AC - Neuroimage (2006)

Bottom Line: Semantic orienting significantly shortened response times to identify word stimuli, showing that it is possible to focus attention on non-perceptual attributes of stimuli to enhance behavioral performance.Semantic-orienting cues engaged parietal and frontal areas that were also involved in spatial orienting, but in addition engaged brain areas associated with semantic analysis of words, such as the left anterior inferior frontal cortex.They also support the existence of a core frontoparietal network, which controls attentional orienting in speeded response tasks independently of the type of expectations, interacting with task-relevant functionally specialized areas to optimize perception and action.

View Article: PubMed Central - PubMed

Affiliation: University of Oxford, Department of Experimental Psychology, South Parks Road, Oxford, OX1 3UD, UK.

ABSTRACT
We investigated the ability to orient attention to a complex, non-perceptual attribute of stimuli-semantic category. Behavioral consequences and neural correlates of semantic orienting were revealed and compared with those of spatial orienting, using event-related functional magnetic-resonance imaging. Semantic orienting significantly shortened response times to identify word stimuli, showing that it is possible to focus attention on non-perceptual attributes of stimuli to enhance behavioral performance. Semantic-orienting cues engaged parietal and frontal areas that were also involved in spatial orienting, but in addition engaged brain areas associated with semantic analysis of words, such as the left anterior inferior frontal cortex. These findings show that attentional orienting selectively engages brain areas with functional specialization for the predicted attributes. They also support the existence of a core frontoparietal network, which controls attentional orienting in speeded response tasks independently of the type of expectations, interacting with task-relevant functionally specialized areas to optimize perception and action.

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Related in: MedlinePlus

Experimental task schematic and behavioral results in Experiments 1 and 2. The cueing stimulus (Experiment 1: ×, +, #; Experiment 2: ×, +) was presented at the beginning of each trial. The cue stayed on the screen during the whole cue-target interval. Targets then appeared in the left or right VF, accompanied by a string of ×'s of the same length in the opposite VF. A fixation point was presented at the end of each trial to help participants refocus on the center of the screen. Experiment 2 did not have a neutral cueing condition. Graphs show behavioral performance (mean of median RTs and standard error) in the semantic and spatial attention conditions for Experiment 1 and Experiment 2.
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fig1: Experimental task schematic and behavioral results in Experiments 1 and 2. The cueing stimulus (Experiment 1: ×, +, #; Experiment 2: ×, +) was presented at the beginning of each trial. The cue stayed on the screen during the whole cue-target interval. Targets then appeared in the left or right VF, accompanied by a string of ×'s of the same length in the opposite VF. A fixation point was presented at the end of each trial to help participants refocus on the center of the screen. Experiment 2 did not have a neutral cueing condition. Graphs show behavioral performance (mean of median RTs and standard error) in the semantic and spatial attention conditions for Experiment 1 and Experiment 2.

Mentions: We designed two event-related fMRI experiments to investigate the behavioral and neural effects of semantic orienting and its relation to spatial orienting. Both experiments used a cued lexical-decision task with a similar structure to the Posner attentional orienting task (Posner, 1980) (Fig. 1). Verbal (word or non-word) stimuli were presented visually at peripheral locations, preceded by symbolic cues carrying predictive semantic or spatial information. Semantic cues predicted the most likely semantic category of the target word (animal or tool), and spatial cues predicted the most likely location of the target words (left or right visual field). Behavioral responses as well as the brain systems supporting both forms of orienting were compared in two the experiments.


Orienting attention to semantic categories.

Cristescu TC, Devlin JT, Nobre AC - Neuroimage (2006)

Experimental task schematic and behavioral results in Experiments 1 and 2. The cueing stimulus (Experiment 1: ×, +, #; Experiment 2: ×, +) was presented at the beginning of each trial. The cue stayed on the screen during the whole cue-target interval. Targets then appeared in the left or right VF, accompanied by a string of ×'s of the same length in the opposite VF. A fixation point was presented at the end of each trial to help participants refocus on the center of the screen. Experiment 2 did not have a neutral cueing condition. Graphs show behavioral performance (mean of median RTs and standard error) in the semantic and spatial attention conditions for Experiment 1 and Experiment 2.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2651199&req=5

fig1: Experimental task schematic and behavioral results in Experiments 1 and 2. The cueing stimulus (Experiment 1: ×, +, #; Experiment 2: ×, +) was presented at the beginning of each trial. The cue stayed on the screen during the whole cue-target interval. Targets then appeared in the left or right VF, accompanied by a string of ×'s of the same length in the opposite VF. A fixation point was presented at the end of each trial to help participants refocus on the center of the screen. Experiment 2 did not have a neutral cueing condition. Graphs show behavioral performance (mean of median RTs and standard error) in the semantic and spatial attention conditions for Experiment 1 and Experiment 2.
Mentions: We designed two event-related fMRI experiments to investigate the behavioral and neural effects of semantic orienting and its relation to spatial orienting. Both experiments used a cued lexical-decision task with a similar structure to the Posner attentional orienting task (Posner, 1980) (Fig. 1). Verbal (word or non-word) stimuli were presented visually at peripheral locations, preceded by symbolic cues carrying predictive semantic or spatial information. Semantic cues predicted the most likely semantic category of the target word (animal or tool), and spatial cues predicted the most likely location of the target words (left or right visual field). Behavioral responses as well as the brain systems supporting both forms of orienting were compared in two the experiments.

Bottom Line: Semantic orienting significantly shortened response times to identify word stimuli, showing that it is possible to focus attention on non-perceptual attributes of stimuli to enhance behavioral performance.Semantic-orienting cues engaged parietal and frontal areas that were also involved in spatial orienting, but in addition engaged brain areas associated with semantic analysis of words, such as the left anterior inferior frontal cortex.They also support the existence of a core frontoparietal network, which controls attentional orienting in speeded response tasks independently of the type of expectations, interacting with task-relevant functionally specialized areas to optimize perception and action.

View Article: PubMed Central - PubMed

Affiliation: University of Oxford, Department of Experimental Psychology, South Parks Road, Oxford, OX1 3UD, UK.

ABSTRACT
We investigated the ability to orient attention to a complex, non-perceptual attribute of stimuli-semantic category. Behavioral consequences and neural correlates of semantic orienting were revealed and compared with those of spatial orienting, using event-related functional magnetic-resonance imaging. Semantic orienting significantly shortened response times to identify word stimuli, showing that it is possible to focus attention on non-perceptual attributes of stimuli to enhance behavioral performance. Semantic-orienting cues engaged parietal and frontal areas that were also involved in spatial orienting, but in addition engaged brain areas associated with semantic analysis of words, such as the left anterior inferior frontal cortex. These findings show that attentional orienting selectively engages brain areas with functional specialization for the predicted attributes. They also support the existence of a core frontoparietal network, which controls attentional orienting in speeded response tasks independently of the type of expectations, interacting with task-relevant functionally specialized areas to optimize perception and action.

Show MeSH
Related in: MedlinePlus