This article applies to:
E-Prime 3.0
E-Prime 1.0
Detail
Experiment Author: Susan Campbell. Adapted from STEP and used with permission of Brian MacWhinney
Experiment Description
Participants are given a cue as to the location in the visual field where a stimulus will appear. In some blocks, they are told which location is most likely (probability of 79 out of 120) for that block, and in others, the location is cued at the beginning of each trial.
Targets are X'es in 4 numbered positions across the screen, with a fixation point in the middle and a cue at the bottom of the display. There are also catch trials where no target is present. Participants tend to respond quickest to cues that come at the beginning of a trial, then to those at the beginning of a block, then to un-cued stimuli.
Experiment Instructions
In this experiment participants respond to stimuli that appear in one of four pre-determined locations for each trial. X'es appear in one of four numbered positions on the screen. Press the spacebar if an "X" appears on screen. Some trials are blank with no target stimuli. Do not press any key in this case. This experiment has 100 trials.
Experiment Citation
Posner, M.I., Snyder, C.R.R., Davidson, B.J. (1980) Attention and the detection of signals. Journal of Experimental Psychology: General 109, 160-174.
Cited Experiment Abstract
Detection of a visual signal requires information to reach a system capable of eliciting arbitrary responses required by the experimenter. Detection latencies are reduced when subjects receive a cue that indicates where in the visual field the signal will occur. This shift in efficiency appears to be due to an alignment (orienting) of the central attentional system with the pathways to be activated by the visual output.
It would also be possible to describe these results as being due to a reduced criterion at the expected target position. However, this description ignores important constraints about the way in which expectancy improves performance. First, when subjects are cued on each trial, they show stronger expectancy effects than when a probability position is held constant for a block, indicating the active nature of the expectancy. Second, while information on spatial position improves performance, information of the form of the stimulus does not. Third, expectancy may lead to improvements in latency without a reduction in accuracy. Fourth, there appears to be little ability to lower the criterion at two positions that are not spatially contiguous.
A framework involving the employment of a limited-capacity attentional mechanism seems to capture these constraints better than the more general language of criterion setting. Using this framework, we find that attention shifts are not closely related to the saccadic eye movement system. For luminance detection the retina appears to be equipotential with respect to attention shifts, since costs to unexpected stimuli are similar whether foveal or peripheral. These results appear to provide an important model system for the study of the relationship between attention and the structure of the visual system.
Works Cited by the Experiment
Duncan, J. The demonstration of capacity limitation. Cognitive Psychology, 1980, 12, 75-96.
Eason, R.G., Harter, R., & White, C.T. Effects of attention and arousal on visually evoked cortical potentials and reaction time in man. Physiology and Behavior, 1969, 4, 283-289.
Engle, F.L. Visual conspicuity, direction attention and retinal locus. Vision Research, 1971, 11, 563-576.
Eriksen, C.W. , & Hoffman, J.E. The extent of processing of noise elements during selective encoding from visual displays. Perception & Psychophysics, 1973, 14, 155-160.
Goldberg, M.E., & Wurtz, R.H. Activity of superior colliculus in behaving monkeys: II. Effects of attention on neuronal response. Journal of Neurophysiology, 1972, 35,560-574.
Green, D.M., & Birdsall, R.G. Detection and recognition. Psychological Review, 1978, 85, 192-206.
Green, D.M., & Swets, J.A. Signal detection theory and psychophysics. Huntington, NY: Krieger, 1974.
Grindley, C.G., & Townsend, V. Voluntary attention in peripheral vision and its effects on acuity and differential thresholds. Quarterly Journal of Experimental Psychology, 1968, 20, 11-19.
Hecht, S., Schlaer, S., & Pirenne, M.H. Energy, quanta, and vision. Journal of General Psychology, 1942, 25, 819-840.
LaBerge, D.S., & Samuels, J. Toward a theory of automatic information processing in reading. Cognitive Psychology, 1974, 6, 293-323.
Lappin, J.S., & Uttal, W.R. Does prior knowledge facilitate the detection of visual targets in random noise? Perception & Psychophysics, 1976, 20, 367-374.
Mertens, J.J. Influence of knowledge of target location upon the probability of observation of peripherally observable test flashes. Journal of the Optical Society of America, 1956, 46, 1060-1070.
Moray, N. Where is attention limited? A survey and a model. Acta Psychologica, 1967, 27, 84-92.
Mowrer, O.H. Preparatory set (expectancy) -- further evidence of its central locus. Journal of Experimental Psychology, 1941, 28, 116-133.
Norman, D.A. Toward a theory of memory and attention. Psychological Review, 1968, 75, 523-536.
Posner, M.I. Chronomeric explorations of mind. Hillsdale, NJ: Erlbaum 1978.
Posner, M.I. Orienting of attention. Quarterly Journal of Experimental Psychology, 1980, 32, 3-25.
Posner, M.I., Nissen, M.J., & Ogden, W.C. Attended and unattended processing modes; The role of set for spatial location. In H.L. Pick & I.J. Saltzman (Eds.), Modes of perceiving and processing information. Hillsdale, NJ: Erlbaum, 1978.
Sekuler, R., & Ball, K. Mental set alters visibility of moving targets. Science, 1977, 198, 60-62.
Shaw, M., & Shaw, P. Optimal allocation of cognitive resources to spatial location. Journal of Experimental Psychology: Human Perception and Performance, 1977, 3, 201-211.
Shiffrin, R.M., & Gardner, G.T. Visual processing capacity and attentional control. Journal of Experimental Psychology, 1972, 93, 72-82.
Shulman, G.L., Remington, R.W., & McLean, J.P. Moving attention through space. Journal of Experimental Psychology: Human Perception and Performance, 1979, 5, 522-526.
Sokolov, E.N. Perception and the conditional reflex. New York: MacMillan, 1963.
Sperling, G., & Melchner, M.J. Visual search, visual attention and the attention operating characteristic. In J. Requin (Ed.), Attention and performance VII. New York: Academic Press, 1976.
Von Voorhis, S., & Hillyard, S.A. Visual evoked potentials and selective attention to points in space. Perception & Psychophysics, 1977, 25, 54-62.
Wurtz, R.H., & Mohler, C.W. Organization of monkey superior colliculus: Enhanced visual response of superficial layer cells. Journal of Neurophysiology, 1976, 39, 745-765.
See Also:
STEP: Visual Attention Within and Around the Field of Focal Attention [35115]
STEP: Does IOR Occur in Discrimination Tasks? [35256]
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