Spatial gradients of visual attention: behavioral and electrophysiological evidence.

The spatial distribution of visual attention was investigated by measuring target detectability (d') and event-related brain potentials (ERPs) to stimuli at varying distances from an attended locus. Vertical bars were flashed rapidly in random order to 1 of 3 locations: one in each of the lateral visual fields and one on the vertical meridian above the fixation point. Subjects maintained eye fixation while directing their attention to 1 of the 3 locations for the duration of each 1.75 min run. Their primary task was to detect infrequent, shorter target bars at the attended location. A secondary task was to respond to shorter target bars at either of the 2 unattended locations if they 'happened to notice them' (without trying to detect them). ERPs and d' scores were obtained to the lateral field stimuli both when they were specifically attended (primary task), as well as when attention was focused upon midline or opposite-field flashes (secondary task). Both d' scores and the amplitudes of the P135 and N190 waves decreased progressively as attention was directed to locations increasingly distant from a given lateral stimulus. These results support 'gradient' models of the spatial distribution of visual attention.

[1]  Howard S. Bashinski,et al.  Enhancement of perceptual sensitivity as the result of selectively attending to spatial locations , 1980, Perception & psychophysics.

[2]  C. Eriksen,et al.  Allocation of attention in the visual field. , 1985, Journal of experimental psychology. Human perception and performance.

[3]  M. D. Rugg,et al.  Modulation of visual event-related potentials by spatial and non-spatial visual selective attention , 1987, Neuropsychologia.

[4]  M. Posner,et al.  Attention and the detection of signals. , 1980, Journal of experimental psychology.

[5]  J. Jonides.  Towards a model of the mind's eye's movement. , 1980, Canadian journal of psychology.

[6]  S. Hillyard,et al.  Selective attention to color and location: An analysis with event-related brain potentials , 1984, Perception & psychophysics.

[7]  R. Homan,et al.  Cerebral location of international 10-20 system electrode placement. , 1987, Electroencephalography and clinical neurophysiology.

[8]  S. Hillyard,et al.  Visual evoked potentials and selective attention to points in space , 1977 .

[9]  S A Hillyard,et al.  The spatial orienting of attention: sensory facilitation or response bias? , 1987, Electroencephalography and clinical neurophysiology. Supplement.

[10]  R Coppola,et al.  A new system for gray-level surface distribution maps of electrical activity. , 1982, Electroencephalography and clinical neurophysiology.

[11]  M. R. Harter,et al.  Hemispheric differences in the neural processing of stimulus location and type: Effects of selective attention on visual evoked potentials , 1982, Neuropsychologia.

[12]  R. Eason.  Visual evoked potential correlates of early neural filtering during selective attention , 1981 .

[13]  G. Shulman,et al.  Spatial determinants of the distribution of attention , 1985, Perception & psychophysics.

[14]  R. Klein,et al.  Is Posner's "beam" the same as Treisman's "glue"?: On the relation between visual orienting and feature integration theory. , 1987, Journal of experimental psychology. Human perception and performance.

[15]  M. Russell Harter,et al.  Effects of attention and arousal on visually evoked cortical potentials and reaction time in man , 1969 .

[16]  G. Shulman,et al.  Gradients of spatial attention. , 1986, Acta psychologica.

[17]  S A Hillyard,et al.  Sensory gating as a physiological mechanism for visual selective attention. , 1987, Electroencephalography and clinical neurophysiology. Supplement.

[18]  S. Hillyard,et al.  Endogenous brain potentials associated with selective auditory attention. , 1980, Electroencephalography and clinical neurophysiology.

[19]  S. A. Hillyard,et al.  The Spatial Allocation of Visual Attention as Indexed by Event-Related Brain Potentials , 1987, Human factors.

[20]  C. J. Downing.  Expectancy and visual-spatial attention: effects on perceptual quality. , 1988, Journal of experimental psychology. Human perception and performance.