scholarly journals Attention and Signal Detection

Information ◽  
2019 ◽  
Vol 10 (8) ◽  
pp. 254 ◽  
Author(s):  
Reeves

In this paper, I first review signal detection theory (SDT) approaches to perception, and then discuss why it is thought that SDT theory implies that increasing attention improves performance. Our experiments have shown, however, that this is not necessarily true. Subjects had either focused attention on two of four possible locations in the visual field, or diffused attention to all four locations. The stimuli (offset letters), locations, conditions, and tasks were all known in advance, responses were forced-choice, subjects were properly instructed and motivated, and instructions were always valid—conditions which should optimize signal detection. Relative to diffusing attention, focusing attention indeed benefitted discrimination of forward from backward pointing Es. However, focusing made it harder to identify a randomly chosen one of 20 letters. That focusing can either aid or disrupt performance, even when cues are valid and conditions are idealized, is surprising, but it can also be explained by SDT, as shown here. These results warn the experimental researcher not to confuse focusing attention with enhancing performance, and warn the modeler not to assume that SDT is unequivocal.

2009 ◽  
Vol 109 (1) ◽  
pp. 270-284 ◽  
Author(s):  
Joceline Rogé ◽  
Catherine Gabaude

The goal of this study was to establish whether the deterioration of the useful visual field due to sleep deprivation and age in a screen monitoring activity could be explained by a decrease in perceptual sensitivity and/or a modification of the participant's decision criterion (two indices derived from signal detection theory). In the first experiment, a comparison of three age groups (young, middle-aged, elderly) showed that perceptual sensitivity decreased with age and that the decision criterion became more conservative. In the second experiment, measurement of the useful visual field was carried out on participants who had been deprived of sleep the previous night or had a complete night of sleep. Perceptual sensitivity significantly decreased with sleep debt, and sleep deprivation provoked an increase in the participants' decision criterion. Moreover, the comparison of two age groups (young, middle-aged) indicated that sensitivity decreased with age. The value of using these two indices to explain the deterioration of useful visual field is discussed.


2018 ◽  
Vol 119 (4) ◽  
pp. 1485-1496 ◽  
Author(s):  
Torin K. Clark ◽  
Yongwoo Yi ◽  
Raquel C. Galvan-Garza ◽  
María Carolina Bermúdez Rey ◽  
Daniel M. Merfeld

When forced to choose humans often feel uncertain. Investigations of human perceptual decision-making often employ signal detection theory, which assumes that even when uncertain all available information is fully utilized. However, other studies have suggested or assumed that, when uncertain, human subjects guess totally at random, ignoring available information. When uncertain, do humans simply guess totally at random? Or do humans fully utilize complete information? Or does behavior fall between these two extremes yielding “above chance” performance without fully utilizing complete information? While it is often assumed complete information is fully utilized, even when uncertain, to our knowledge this has never been experimentally confirmed. To answer this question, we combined numerical simulations, theoretical analyses, and human studies performed using a self-motion direction-recognition perceptual decision-making task (did I rotate left or right?). Subjects were instructed to make forced-choice binary (left/right) and trinary (left/right/uncertain) decisions when cued following each stimulus. Our results show that humans 1) do not guess at random when uncertain and 2) make binary and trinary decisions equally well. These findings show that humans fully utilize complete information when uncertain for our perceptual decision-making task. This helps unify signal detection theory and other models of forced-choice decision-making which allow for uncertain responses. NEW & NOTEWORTHY Humans make many perceptual decisions every day. But what if we are uncertain? While many studies assume that humans fully utilize complete information, other studies have suggested and/or assumed that when we're uncertain and forced to decide, information is not fully utilized. While humans tend to perform above chance when uncertain, no earlier study has tested whether available information is fully utilized. Our results show that humans make fully informed decisions even when uncertain.


2017 ◽  
Vol 118 (5) ◽  
pp. 2636-2653 ◽  
Author(s):  
Koeun Lim ◽  
Wei Wang ◽  
Daniel M. Merfeld

Humans can subjectively yet quantitatively assess choice confidence based on perceptual precision even when a perceptual decision is made without an immediate reward or feedback. However, surprisingly little is known about choice confidence. Here we investigate the dynamics of choice confidence by merging two parallel conceptual frameworks of decision making, signal detection theory and sequential analyses (i.e., drift-diffusion modeling). Specifically, to capture end-point statistics of binary choice and confidence, we built on a previous study that defined choice confidence in terms of psychophysics derived from signal detection theory. At the same time, we augmented this mathematical model to include accumulator dynamics of a drift-diffusion model to characterize the time dependence of the choice behaviors in a standard forced-choice paradigm in which stimulus duration is controlled by the operator. Human subjects performed a subjective visual vertical task, simultaneously reporting binary orientation choice and probabilistic confidence. Both binary choice and confidence experimental data displayed statistics and dynamics consistent with both signal detection theory and evidence accumulation, respectively. Specifically, the computational simulations showed that the unbounded evidence accumulator model fits the confidence data better than the classical bounded model, while bounded and unbounded models were indistinguishable for binary choice data. These results suggest that the brain can utilize mechanisms consistent with signal detection theory—especially when judging confidence without time pressure. NEW & NOTEWORTHY We found that choice confidence data show dynamics consistent with evidence accumulation for a forced-choice subjective visual vertical task. We also found that the evidence accumulation appeared unbounded when judging confidence, which suggests that the brain utilizes mechanisms consistent with signal detection theory to determine choice confidence.


1995 ◽  
Vol 40 (10) ◽  
pp. 972-972
Author(s):  
Jerome R. Busemeyer

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