Signal Detection Theory Lab Intro PDF

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Running head:SIGNAL DETECTION THEORY

Signal Detection Theory: Detecting A 10- Dot Signal In 3 Levels Of Noise

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SIGNAL DETECTION THEORY

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Signal Detection Theory: Detecting A 10- Dot Signal In 3 Levels Of Noise Signal Detection theory has to do with an individual’s ability to detect a signal. The question being asking in this study is, is a person’s ability to detect the signal affected by the amount of noise surrounding it? One study conducted by Soto, Vucovich, and Ashby used Signal Detection Theory to create a new framework that would allow for, “the study of separability of brain representations of face identity and emotional expression (neutral/sad) in a human fMRI study with male and female participants” (2018). This study was important because it introduced a new concept that “encoding analysis of neuroimaging data or a psychophysical study allow inferences to be made about encoding separability”(Soto et al., 2018). This study emphasizes the importance of studying Signal Detection Theory, as the basic theory backing it is derived from Signal Detection Theory. Another interesting study uses Signal Detection Theory “to compare the sensitivity of antisocial and control participants to emotional stimuli” (Barbosa et al., 2018). They decided to use Signal Detection Theory because other studies yielded inconsistent results in the emotional responses of antisocial individuals (Barbosa et al., 2018). The results of this study showed that male recidivist offenders had worse abilities to discriminate between different levels of arousal and valence of emotional stimuli(Barbosa et al., 2018). In this experiment, participants are asked to determine whether they see a 10-dot slanted line in the presence of a varying number of dots. These dots appear as a star field. Participants go through 60 trials in which they have to determine whether the signal is present in each star field.

SIGNAL DETECTION THEORY

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The rationale behind the experiment is that it will be harder for participants to detect the signal when there is a lot of noise surrounding it. Also, the more trials a participant goes through in which there is a lot of background noise, the more likely a participant will be to think that they have detected the signal. The dependent variable is the participants ability to accurately detect whether the signal is present or not present. The independent variable is the amount of noise present. In this study, the 3 independent variables are 144 dots, 400 dots, and 1000 dots. An increased level of noise will make it much harder for the participants to detect the signal. An increased level of noise will also make it more likely that participants report seeing a signal that isn’t there.

SIGNAL DETECTION THEORY

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Barbosa, F., Almeida, P. R., Ferreira, S. F., & Marques, T. J. (2016). Using signal detection theory in the analysis of emotional sensitivity of male recidivist offenders. Criminal Behaviour and Mental Health, 26(1), 18–29. Soto, F. A., Vucovich, L. E., & Ashby, F. G. (2018). Linking signal detection theory and encoding models to reveal independent neural representations from neuroimaging data. PLoS Computational Biology, 14(10), 1–42....