http://app.psychonomic-journals.org/content/72/6/1510.abstract

Voluntary attention increases perceived spatial frequency

1. Jared Abrams,
2. Antoine Barbot and
3. Marisa Carrasco

New York University, New York, New York

Abstract

Voluntary covert attention selects relevant sensory information for
prioritized processing. The behavioral and neural consequences of such
selection have been extensively documented, but its phenomenology has
received little empirical investigation. Involuntary attention increases
perceived spatial frequency (Gobell & Carrasco, 2005), but involuntary
attention can differ from voluntary attention in its effects on
performance in tasks mediated by spatial resolution (Yeshurun, Montagna, &
Carrasco, 2008). Therefore, we ask whether voluntary attention affects the
subjective appearance of spatial frequency—a fundamental dimension of
visual perception underlying spatial resolution. We used a demanding rapid
serial visual presentation task to direct voluntary attention and measured
perceived spatial frequency at the attended and unattended locations.
Attention increased the perceived spatial frequency of suprathreshold
stimuli and also improved performance on a concurrent orientation
discrimination task. In the control experiment, we ruled out response bias
as an alternative account by using a lengthened interstimulus interval,
which allows observers to disengage attention from the cued location. In
contrast to the main experiment, the observers showed neither increased
perceived spatial frequency nor improved orientation discrimination at the
attended location. Thus, this study establishes that voluntary attention
increases perceived spatial frequency. This phenomenological consequence
links behavioral and neurophysiological studies on the effects of
attention.

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