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Orientation sensitivity at different stages of object processing: evidence from repetition priming and naming.

Harris IM, Dux PE, Benito CT, Leek EC - PLoS ONE (2008)

Bottom Line: Significant priming was obtained for prime durations above 70 ms, but not for prime durations of 16 ms and 47 ms, and did not vary as a function of prime orientation.In contrast, naming the same objects that served as primes resulted in orientation-dependent reaction time costs.These results suggest that initial processing of object identity is mediated by orientation-independent information and that orientation costs in performance arise when objects are consolidated in visual short-term memory in order to be reported.

View Article: PubMed Central - PubMed

Affiliation: School of Psychology, University of Sydney, Sydney, Australia. irina@psych.usyd.edu.au

ABSTRACT

Background: An ongoing debate in the object recognition literature centers on whether the shape representations used in recognition are coded in an orientation-dependent or orientation-invariant manner. In this study, we asked whether the nature of the object representation (orientation-dependent vs orientation-invariant) depends on the information-processing stages tapped by the task.

Methodology/findings: We employed a repetition priming paradigm in which briefly presented masked objects (primes) were followed by an upright target object which had to be named as rapidly as possible. The primes were presented for variable durations (ranging from 16 to 350 ms) and in various image-plane orientations (from 0 degrees to 180 degrees, in 30 degrees steps). Significant priming was obtained for prime durations above 70 ms, but not for prime durations of 16 ms and 47 ms, and did not vary as a function of prime orientation. In contrast, naming the same objects that served as primes resulted in orientation-dependent reaction time costs.

Conclusions/significance: These results suggest that initial processing of object identity is mediated by orientation-independent information and that orientation costs in performance arise when objects are consolidated in visual short-term memory in order to be reported.

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Mean reaction times for naming rotated objects in Experiment 2, plotted as a function of object orientation.Error bars represent within-subject s.e.m for the orientation effect.
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pone-0002256-g003: Mean reaction times for naming rotated objects in Experiment 2, plotted as a function of object orientation.Error bars represent within-subject s.e.m for the orientation effect.

Mentions: Naming accuracy was reasonably high despite the lack of practice and feedback (88% correct overall, ranging across orientations from 84–92%). There was no effect of orientation on accuracy (F<1). Mean RT for correct responses are shown in Figure 3 and clearly indicate an orientation-dependent pattern of RT, which increased systematically as a function of orientation. Analyses confirmed a significant linear trend in the data, F(1,14) = 9.23, p<.01, η2 = .40, with no higher-order components. The slope of the naming function was 0.67 ms/deg. Thus, on average, there was a cost of 121 ms when naming objects rotated by 180°, compared to upright objects.


Orientation sensitivity at different stages of object processing: evidence from repetition priming and naming.

Harris IM, Dux PE, Benito CT, Leek EC - PLoS ONE (2008)

Mean reaction times for naming rotated objects in Experiment 2, plotted as a function of object orientation.Error bars represent within-subject s.e.m for the orientation effect.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2384001&req=5

pone-0002256-g003: Mean reaction times for naming rotated objects in Experiment 2, plotted as a function of object orientation.Error bars represent within-subject s.e.m for the orientation effect.
Mentions: Naming accuracy was reasonably high despite the lack of practice and feedback (88% correct overall, ranging across orientations from 84–92%). There was no effect of orientation on accuracy (F<1). Mean RT for correct responses are shown in Figure 3 and clearly indicate an orientation-dependent pattern of RT, which increased systematically as a function of orientation. Analyses confirmed a significant linear trend in the data, F(1,14) = 9.23, p<.01, η2 = .40, with no higher-order components. The slope of the naming function was 0.67 ms/deg. Thus, on average, there was a cost of 121 ms when naming objects rotated by 180°, compared to upright objects.

Bottom Line: Significant priming was obtained for prime durations above 70 ms, but not for prime durations of 16 ms and 47 ms, and did not vary as a function of prime orientation.In contrast, naming the same objects that served as primes resulted in orientation-dependent reaction time costs.These results suggest that initial processing of object identity is mediated by orientation-independent information and that orientation costs in performance arise when objects are consolidated in visual short-term memory in order to be reported.

View Article: PubMed Central - PubMed

Affiliation: School of Psychology, University of Sydney, Sydney, Australia. irina@psych.usyd.edu.au

ABSTRACT

Background: An ongoing debate in the object recognition literature centers on whether the shape representations used in recognition are coded in an orientation-dependent or orientation-invariant manner. In this study, we asked whether the nature of the object representation (orientation-dependent vs orientation-invariant) depends on the information-processing stages tapped by the task.

Methodology/findings: We employed a repetition priming paradigm in which briefly presented masked objects (primes) were followed by an upright target object which had to be named as rapidly as possible. The primes were presented for variable durations (ranging from 16 to 350 ms) and in various image-plane orientations (from 0 degrees to 180 degrees, in 30 degrees steps). Significant priming was obtained for prime durations above 70 ms, but not for prime durations of 16 ms and 47 ms, and did not vary as a function of prime orientation. In contrast, naming the same objects that served as primes resulted in orientation-dependent reaction time costs.

Conclusions/significance: These results suggest that initial processing of object identity is mediated by orientation-independent information and that orientation costs in performance arise when objects are consolidated in visual short-term memory in order to be reported.

Show MeSH