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Abstract:
Abstract: In this work we study the selective attention
mechanism in the context of visual search. We present a
neurodynamical model consisting of different pools of
interconnected phase oscillators. Each oscillator is described by
an integrate-and-fire type equation. The model is used to simulate
visual search tasks. We present numerical calculations for the
cases of feature and conjunction searches. The neural system is
build up with parallel processes only. Independent competition
mechanisms along each feature dimension are also taken into
account. Visual attention appears as an emergent property of the
dynamic of the system resulting from the temporal synchronization
of the pools which bind the features of the searched target. For
the feature search no dependence of the reaction time with the
display size is observed whereas for the conjunction search the
theoretical results predict a linear increasing reaction time as
the display size increases, both results in good agreement with the
corresponding experimental data. Therefore, we show that the time
course observed in the psycophysical visual search experiments can
be explained within a purely parallel dynamic, with out assuming
priority maps and serial spotlight mechanisms.
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