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Psychophysical Measurement of Human Oral Experience
Published in Alan R. Hirsch, Nutrition and Sensation, 2023
Derek J. Snyder, Linda M. Bartoshuk
While elegant, this procedure raises concerns that warrant serious consideration. Test efficiency is extremely important; too few trials render the procedure unreliable, but too many trials can lead to adaptation and fatigue. In addition, signal detection theory (Green and Swets 1966) shows that individuals use different criteria when deciding how much sensory change warrants a response: One person may respond to the slightest hint of change, while another may want to be extremely confident that change has occurred before responding. As a result, participants show bias toward responses already made (i.e., habituation errors), but they may also change their responses prematurely when they believe an actual change is imminent (i.e., anticipation errors). Shifts in these criteria can occur over many trials, highlighting the need for concise testing methods.
Signal detection theory
Published in Stanley A. Gelfand, Hearing, 2017
Correcting for chance success is surely an improvement over approaches that do not account for guessing, but it still does not really separate the effects of auditory factors (sensitivity) and nonauditory factors. In essence, this process high lights the importance of nonauditory factors in determining the response, because the very fact that the subject said “yes” to catch trials and “no” to stimulus trials indicates that his decision to respond was affected by more than just sensitivity to the stimulus. Signal detection theory is concerned with the factors that enter into this decision.
What gets measured, gets manipulated
Published in Sidney Dekker, The Safety Anarchist, 2017
In hindsight, it can be easy to dig out the things that turned out critical for an eventual drift into a spectacular failure. What is much harder is that none of them ever were reported as incidents, and the measures a bureaucracy takes of its operations (like LTIs) have no relationship to drift other than perhaps an inverse one (Dekker, 2011). Bureaucratic mechanisms for incident analysis and reporting have great difficulty picking up the subtle signs of drift: Weak signals are an attractive concept but one that often turns out to be illusory from a management perspective. This is because analysing weak signals means nothing other than analysing those parts of the current matrix that it has been decided not to analyse. What appears to be simple when expressed in this way actually turns out to be very complicated, for a number of reasons.(Amalberti, 2013, p. 70) The reasons Amalberti gives include the vast cost of extending bureaucratic monitoring to be able to pick up ‘weak signals,’ the absence of accident models that can meaningfully account for ‘weak signals’ as sentinels of worse to come, and of course the inherent selection that goes on when people decide what counts as a ‘weak signal.’ A signal is constructed as weak (and, for that matter, as a signal) by the people who label them that way. And, for that matter, signal detection theory (which formally models this sort of problem) makes no inherent distinction between ‘weak’ or ‘strong’ signals, but only between (amounts of) signal and noise. Perhaps there is one source, Amalberti suggests, that can generate the sorts of signals that might be missed by bureaucratic data collection and reporting, and that is from whistle-blowers. These, after all, tend to pick up and make visible what is left unexamined by the safety bureaucracy (what it, in other words, would miss, ignore or dismiss as ‘noise’).
Effects of Moderate-to-Vigorous Acute Exercise on Conscious Perception and Visual Awareness
Published in Journal of Motor Behavior, 2023
Binn Zhang, Xiaoxu Meng, Yanglan Yu, Yaogang Han, Ying Liu
The effects of acute exercise (exercise, control) on reports of visual awareness were examined. To raise the sensitivity of statistical testing, according to signal detection theory, we calculated d‘ (the most important measure of signal detection theory sensitivity) and β, the likelihood ratio, an index of response bias. The results showed that d‘ was significantly higher for cognitive tasks completed after exercise, compared with cognitive tasks completed after reading (exercise, mean ± SEM = 1.23 ± 0.17; control, mean ± SEM = 0.87 ± 0.16；paired t-test, t17 = − 2.57, p = 0.020) (Figure 3). However, no such difference was found for likelihood ratio (β) (exercise, mean ± SEM = 1.82 ± 0.53; control, mean ± SEM = 1.67 ± 0.39；paired t-test, t17 = − 0.37, p = 0.72). To better understand the difference in d‘, we compared hit and false alarm rates separately. We then conducted paired t-tests on subjects’ performance on speed change-present and speed change-absent trials, respectively (based on their responses to Question 2). Subjects were more likely to report the existence of speed changes during cognitive tasks completed after exercise (hit rate, mean ± SEM = 67.7 ± 4.5%), compared with cognitive tasks completed after reading (hit rate, mean ± SEM = 59.1 ± 4.8%) (paired t-test, t17 = − 2.00, p = 0.062, marginally significant) (Figure 4). For speed change-absent trials, there was no significant difference in false alarm rate between experimental conditions (exercise, mean ± SEM = 30.6 ± 4.9%; control, mean ± SEM = 31.7 ± 5.3%；paired t-test, t17 = 0.29, p = 0.78).
Transcranial Direct Current Stimulation Reduces the Negative Impact of Mental Fatigue on Swimming Performance
Published in Journal of Motor Behavior, 2022
Elahe Nikooharf Salehi, Saeed Jaydari Fard, Shapour Jaberzadeh, Maryam Zoghi
A big limitation is gender effect because only male swimmers were included in this study. A similar study on the females should be also conducted. Future studies should use tDCS with neuroimaging to examine the underlying mechanism of action of tDCS. Furthermore, we used a single-blinded approach with the examiner not being blinded to the tDCS conditions. So, future studies should consider using a double blinded approach. Finally, subjects’ verbal reports on the differences between the tDCS stimulations may be less sensitive to any perceived differences than through a signal detection procedure. We suggest that future research should applied the signal detection theory to examine whether the experimental manipulation affects the participants' ability to detect the target or the participants' response bias. As this study was the first study that used DLPFC-tDCS to counteract the adverse effects of mental fatigue in an athlete population, the findings should be confirmed by follow-up studies in a double-blinded study.
Establishing the cut-off scores for the severity ranges of schizophrenia on the BPRS-6 scale: findings from the REAP-AP
Published in Psychiatry and Clinical Psychopharmacology, 2019
Seon-Cheol Park, Eun Young Jang, Kiwon Kim, Hoseon Lee, Joonho Choi, Amitava Dan, Arshad Hussain, Andi Jayalangkara Tanra, Takahiro A. Kato, Kok Yoon Chee, Sih-Ku Lin, Chay Hoon Tan, Afzal Javed, Norman Sartorius, Naotaka Shinfuku, Yong Chon Park
The exploratory receiver operating characteristic (ROC) curve analyses were conducted to establish the optimal cut-off scores for the remission and severity ranges (mild, moderate, and severe) in patients with schizophrenia. As described elsewhere [18], this statistical method was developed from the signal-detection theory and was frequently used in biological and behavioural studies. In terms of calculating overall predictor performance, the sensitivity and specificity of all possible threshold levels were considered to determine the cut-off score generating the lowest number of false positives and false negatives. The Mokken scale analysis was conducted using R version 3.4.3 (https://www.r-project.org/) and the Pearson correlation and ROC curve analyses were conducted using IBM SPSS 24 (IBM Co., Armonk, NY, USA).