@article{TimmeWolffEnglertetal.2022, author = {Timme, Sinika and Wolff, Wanja and Englert, Chris and Brand, Ralf}, title = {Tracking Self-Control - Task Performance and Pupil Size in a Go/No-Go Inhibition Task}, series = {Frontiers in Psychology}, volume = {13}, journal = {Frontiers in Psychology}, publisher = {Frontiers}, address = {Lausanne, Schweiz}, issn = {1664-1078}, doi = {10.3389/fpsyg.2022.915016}, pages = {11}, year = {2022}, abstract = {There is an ongoing debate about how to test and operationalize self-control. This limited understanding is in large part due to a variety of different tests and measures used to assess self-control, as well as the lack of empirical studies examining the temporal dynamics during the exertion of self-control. In order to track changes that occur over the course of exposure to a self-control task, we investigate and compare behavioral, subjective, and physiological indicators during the exertion of self-control. Participants completed both a task requiring inhibitory control (Go/No-Go task) and a control task (two-choice task). Behavioral performance and pupil size were measured during the tasks. Subjective vitality was measured before and after the tasks. While pupil size and subjective vitality showed similar trajectories in the two tasks, behavioral performance decreased in the inhibitory control-demanding task, but not in the control task. However, behavioral, subjective, and physiological measures were not significantly correlated. These results suggest that there is a disconnect between different measures of self-control with high intra- and interindividual variability. Theoretical and methodological implications for self-control theory and future empirical work are discussed.}, language = {en} } @article{BeurskensSteinbergAntoniewiczetal.2016, author = {Beurskens, Rainer and Steinberg, Fabian and Antoniewicz, Franziska and Wolff, Wanja and Granacher, Urs}, title = {Neural Correlates of Dual-Task Walking: Effects of Cognitive versus Motor Interference in Young Adults}, series = {Neural plasticity}, journal = {Neural plasticity}, publisher = {Hindawi}, address = {London}, issn = {2090-5904}, doi = {10.1155/2016/8032180}, pages = {9}, year = {2016}, abstract = {Walking while concurrently performing cognitive and/or motor interference tasks is the norm rather than the exception during everyday life and there is evidence from behavioral studies that it negatively affects human locomotion. However, there is hardly any information available regarding the underlying neural correlates of single-and dual-task walking. We had 12 young adults (23.8 +/- 2.8 years) walk while concurrently performing a cognitive interference (CI) or a motor interference (MI) task. Simultaneously, neural activation in frontal, central, and parietal brain areas was registered using a mobile EEG system. Results showed that the MI task but not the CI task affected walking performance in terms of significantly decreased gait velocity and stride length and significantly increased stride time and tempo-spatial variability. Average activity in alpha and beta frequencies was significantly modulated during both CI and MI walking conditions in frontal and central brain regions, indicating an increased cognitive load during dual-task walking. Our results suggest that impaired motor performance during dual-task walking is mirrored in neural activation patterns of the brain. This finding is in line with established cognitive theories arguing that dual-task situations overstrain cognitive capabilities resulting in motor performance decrements.}, language = {en} } @article{WolffSandouqaBrand2016, author = {Wolff, Wanja and Sandouqa, Yaser and Brand, Ralf}, title = {Using, the simple sample count to estimate the frequency of prescription drug neuroenhancement in a sample of Jordan employees}, series = {International journal of drug policy}, volume = {31}, journal = {International journal of drug policy}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0955-3959}, doi = {10.1016/j.drugpo.2015.12.014}, pages = {51 -- 55}, year = {2016}, abstract = {Background: Epidemiological research indicates that the use of prescription drugs to enhance cognitive functioning is prevalent in Western countries, however, research on this phenomenon in Arab countries is lacking. Our study aimed to investigate the frequency of neuroenhancement (NE) using prescription drugs in a sample of employees in Jordan. Methods: A sample of 1186 employees (37.11 +/- 8.37 years old, 495 female), of whom 723 (35.65 +/- 7.53 years old, 396 female) served as teachers, completed a paper-pencil questionnaire. The single sample count technique (SSC) was used in order to secure confidential, self-reporting of prescription drug NE. Results: The 12-month prevalence of NE, estimated with the SSC was 15.43\%. At 26.16\%, the prevalence estimate was markedly higher in the subsample of teachers compared to non-teachers, 0.29\%. Surprisingly, 336 participants did not use the SSC and directly affirmed or denied prescription drug NE. These direct responses yielded a prevalence of 11.57\% for the full sample, 9.73\% for the teachers and 15.60\% for the non-teachers. Conclusion: This is the first study of the frequency of NE in an Arab sample. Results indicate that the use of prescription drug NE is not limited to Western countries and that teachers in Jordan might constitute a high-risk population. Further, participants seem to differ in their use of indirect estimation methods for reporting prescription drug NE. For future research, it might be useful to triangulate standard self reports and indirect estimation methods to assess NE. Possible cultural differences and specific high-risk populations for NE should be investigated further. (C) 2015 Elsevier B.V. All rights reserved.}, language = {en} } @article{WolffSchindlerEnglertetal.2016, author = {Wolff, Wanja and Schindler, Sebastian and Englert, Christoph and Brand, Ralf and Kissler, Johanna}, title = {Uninstructed BIAT faking when ego depleted or in normal state: differential effect on brain and behavior}, series = {BMC neuroscience}, volume = {17}, journal = {BMC neuroscience}, publisher = {BioMed Central}, address = {London}, issn = {1471-2202}, doi = {10.1186/s12868-016-0249-8}, pages = {12}, year = {2016}, abstract = {Background: Deception can distort psychological tests on socially sensitive topics. Understanding the cerebral processes that are involved in such faking can be useful in detection and prevention of deception. Previous research shows that faking a brief implicit association test (BIAT) evokes a characteristic ERP response. It is not yet known whether temporarily available self-control resources moderate this response. We randomly assigned 22 participants (15 females, 24.23 +/- 2.91 years old) to a counterbalanced repeated-measurements design. Participants first completed a Brief-IAT (BIAT) on doping attitudes as a baseline measure and were then instructed to fake a negative doping attitude both when self-control resources were depleted and non-depleted. Cerebral activity during BIAT performance was assessed using high-density EEG. Conclusions: Results indicate that temporarily available self-control resources do not affect overt faking success on a BIAT. However, differences were found on an electrophysiological level. This indicates that while on a phenotypical level self-control resources play a negligible role in deliberate test faking the underlying cerebral processes are markedly different.}, language = {en} } @article{BrandWolffZiegler2016, author = {Brand, Ralf and Wolff, Wanja and Ziegler, Matthias}, title = {Drugs As Instruments: Describing and Testing a Behavioral Approach to the Study of Neuroenhancement}, series = {Frontiers in psychology}, volume = {7}, journal = {Frontiers in psychology}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-1078}, doi = {10.3389/fpsyg.2016.01226}, pages = {11}, year = {2016}, language = {en} } @article{SchindlerWolffKissleretal.2015, author = {Schindler, Sebastian and Wolff, Wanja and Kissler, Johanna M. and Brand, Ralf}, title = {Cerebral correlates of faking}, series = {Frontiers in Behavioral Neuroscience}, volume = {9}, journal = {Frontiers in Behavioral Neuroscience}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1662-5153}, doi = {10.3389/fnbeh.2015.00139}, pages = {1 -- 13}, year = {2015}, abstract = {Direct assessment of attitudes toward socially sensitive topics can be affected by deception attempts. Reaction-time based indirect measures, such as the Implicit Association Test (IAT), are less susceptible to such biases. Neuroscientific evidence shows that deception can evoke characteristic ERP differences. However, the cerebral processes involved in faking an IAT are still unknown. We randomly assigned 20 university students (15 females, 24.65 +/- 3.50 years of age) to a counterbalanced repeated-measurements design, requesting them to complete a Brief-IAT (BIAT) on attitudes toward doping without deception instruction, and with the instruction to fake positive and negative doping attitudes. Cerebral activity during BIAT completion was assessed using high-density EEG. Event-related potentials during faking revealed enhanced frontal and reduced occipital negativity, starting around 150 ms after stimulus presentation. Further, a decrease in the P300 and LPP components was observed. Source analyses showed enhanced activity in the right inferior frontal gyrus between 150 and 200 ms during faking, thought to reflect the suppression of automatic responses. Further, more activity was found for faking in the bilateral middle occipital gyri and the bilateral temporoparietal junction. Results indicate that faking reaction-time based tests alter brain processes from early stages of processing and reveal the cortical sources of the effects. Analyzing the EEG helps to uncover response patterns in indirect attitude tests and broadens our understanding of the neural processes involved in such faking. This knowledge might be useful for uncovering faking in socially sensitive contexts, where attitudes are likely to be concealed.}, language = {en} } @article{EnglertWolff2015, author = {Englert, Chris and Wolff, Wanja}, title = {Ego depletion and persistent performance in a cycling task}, series = {International journal of sport and exercise psychology}, volume = {46}, journal = {International journal of sport and exercise psychology}, number = {2}, publisher = {Pozzi}, address = {Roma}, issn = {0047-0767}, doi = {10.7352/IJSP2015.46.137}, pages = {137 -- 151}, year = {2015}, abstract = {We tested the assumption that persistent performance in an exhausting indoor cycling task would depend on momentarily available self-control strength (N = 20 active participants). In a within-subjects design (two points of measurement, exactly seven days apart), participants' self-control strength was experimentally manipulated (depletion: yes vs. no; order counterbalanced) via the Stroop test before the participants performed a cycling task. In line with our hypothesis, hierarchical linear modelling (HLM) revealed that participants consistently performed worse over a period of 18 minutes when they were ego depleted. In addition, HLM analysis revealed that depleted participants invested less effort in the cycling task, as indicated by their lower heart rate. This effect escalated over time, as indicated by a time x condition interaction. These results indicate that self-control strength is necessary to obtain an optimal level of performance in endurance tasks requiring high levels of persistence. Practical implications are discussed.}, language = {en} } @article{WolffSchindlerBrand2015, author = {Wolff, Wanja and Schindler, Sebastian and Brand, Ralf}, title = {The Effect of Implicitly Incentivized Faking on Explicit and Implicit Measures of Doping Attitude: When Athletes Want to Pretend an Even More Negative Attitude to Doping}, series = {PLoS one}, volume = {10}, journal = {PLoS one}, number = {4}, publisher = {PLoS}, address = {San Fransisco}, issn = {1932-6203}, doi = {10.1371/journal.pone.0118507}, pages = {10}, year = {2015}, abstract = {The Implicit Association Test (IAT) aims to measure participants' automatic evaluation of an attitude object and is useful especially for the measurement of attitudes related to socially sensitive subjects, e.g. doping in sports. Several studies indicate that IAT scores can be faked on instruction. But fully or semi-instructed research scenarios might not properly reflect what happens in more realistic situations, when participants secretly decide to try faking the test. The present study is the first to investigate IAT faking when there is only an implicit incentive to do so. Sixty-five athletes (22.83 years +/- 2.45; 25 women) were randomly assigned to an incentive-to-fake condition or a control condition. Participants in the incentive-to-fake condition were manipulated to believe that athletes with lenient doping attitudes would be referred to a tedious 45-minute anti-doping program. Attitudes were measured with the pictorial doping brief IAT (BIAT) and with the Performance Enhancement Attitude Scale (PEAS). A one-way MANOVA revealed significant differences between conditions after the manipulation in PEAS scores, but not in the doping BIAT. In the light of our hypothesis this suggests that participants successfully faked an exceedingly negative attitude to doping when completing the PEAS, but were unsuccessful in doing so on the reaction time-based test. This study assessed BIAT faking in a setting that aimed to resemble a situation in which participants want to hide their attempts to cheat. The two measures of attitude were differentially affected by the implicit incentive. Our findings provide evidence that the pictorial doping BIAT is relatively robust against spontaneous and naive faking attempts. (B) IATs might be less prone to faking than implied by previous studies.}, language = {en} } @article{EnglertWolff2015, author = {Englert, Chris and Wolff, Wanja}, title = {Neuroenhancement and the strength model of self-control}, series = {Frontiers in psychology}, volume = {6}, journal = {Frontiers in psychology}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-1078}, doi = {10.3389/fpsyg.2015.01425}, pages = {4}, year = {2015}, abstract = {Neuroenhancement (NE), the use of substances as a means to enhance performance, has garnered considerable scientific attention of late. While ethical and epidemiological publications on the topic accumulate, there is a lack of theory-driven psychological research that aims at understanding psychological drivers of NE. In this perspective article we argue that self-control strength offers a promising theory-based approach to further understand and investigate NE behavior. Using the strength model of self-control, we derive two theory-driven perspectives on NE-self-control research. First, we propose that individual differences in state/trait self-control strength differentially affect NE behavior based on one's individual experience of NE use. Building upon this, we outline promising research questions that (will) further elucidate our understanding of NE based on the strength model's propositions. Second, we discuss evidence indicating that popular NE substances (like Methylphenidate) may counteract imminent losses of self-control strength. We outline how further research on NE's effects on the ego-depletion effect may further broaden our understanding of the strength model of self-control.}, language = {en} } @article{BrandWolffThieme2014, author = {Brand, Ralf and Wolff, Wanja and Thieme, Detlef}, title = {brief implicit attitude test identifies substance abuse in bodybuilders}, series = {Substance abuse treatment, prevention, and policy}, volume = {9}, journal = {Substance abuse treatment, prevention, and policy}, publisher = {BioMed Central}, address = {London}, issn = {1747-597X}, doi = {10.1186/1747-597X-9-36}, pages = {10}, year = {2014}, abstract = {Methods: We approached a group of 61 male competitive bodybuilders and collected urine samples for biochemical testing. The pictorial doping Brief Implicit Association Test (BIAT) was used for attitude measurement. This test quantifies the difference in response latencies (in milliseconds) to stimuli representing related concepts (i.e. doping-dislike/like-[health food]).}, language = {en} }