Increasing time spent on the task (i.e., the time-on-task (ToT) effect) often results in mental fatigue. Typical effects of ToT are decreasing levels of task-related motivation and the deterioration of cognitive performance. However, a massive body of research indicates that the detrimental effects can be reversed by extrinsic motivators, for example, providing rewards to fatigued participants. Although several attempts have been made to identify brain areas involved in mental fatigue and related reward processing, the neural correlates are still less understood. In this study, we used the psychomotor vigilance task to induce mental fatigue and blood oxygen-level-dependent functional magnetic resonance imaging to investigate the neural correlates of the ToT effect and the reward effect (i.e., providing extra monetary reward after fatigue induction) in a healthy young sample. Our results were interpreted in a recently proposed neurocognitive framework. The activation of the right middle frontal gyrus, right insula and right anterior cingulate gyrus decreased as fatigue emerged and the cognitive performance dropped. However, after providing an extra reward, the cognitive performance, as well as activation of these areas, increased. Moreover, the activation levels of all of the mentioned areas were negatively associated with reaction times. Our results confirm that the middle frontal gyrus, insula and anterior cingulate cortex play crucial roles in cost-benefit evaluations, a potential background mechanism underlying fatigue, as suggested by the neurocognitive framework.

Nowadays, the limitless availability to the World Wide Web can lead to general Internet misuse and dependence. Currently, smartphone and social media use belong to the most prevalent Internet-related behavioral addiction forms. However, the neurobiological background of these Internet-related behavioral addictions is not sufficiently explored. In this study, these addiction forms were assessed with self-reported questionnaires. Resting-state functional magnetic resonance imaging was acquired for all participants (n = 59, 29 males) to examine functional brain networks. The resting-state networks that were discovered using independent component analysis were analyzed to estimate within network differences. Significant negative associations with social media addiction and smartphone addiction were found in the language network, the lateral visual networks, the auditory network, the sensorimotor network, the executive network and the frontoparietal network. These results suggest that problematic smartphone and social media use are associated with sensory processing and higher cognitive functioning.

Background: Although an increasing number of trials are reported on the treatment of generalized or segmental isolated dystonia, the minimal clinically important difference thresholds for the most frequently reported outcome measures are still undetermined.Objectives: To estimate the minimal clinically important difference for the Burke‐Fahn‐Marsden Dystonia Rating Scale and the 36‐Item Short‐Form Health Survey in generalized or segmental dystonia.Methods: A total of 898 paired examinations of 198 consecutive patients, aged >18 years, with idiopathic and inherited (torsin family 1 member A positive) segmental and generalized isolated dystonia were analyzed. To calculate the minimal clinically important difference thresholds, both anchor‐ and distribution‐based methods were used simultaneously.Results: Any improvement >16.6% or worsening larger than 21.5% on the Burke‐Fahn‐Marsden Dystonia Rating Scale indicates a minimal, yet clinically relevant, change. Threshold values for the Burke‐Fahn‐Marsden Dystonia Disability Scale were 0.5 points for both decline and improvement. Cut‐off scores for the Physical Component Summary, the Mental Component Summary, and the Global (Total or Overall) Score of the 36‐Item Short‐Form Health Survey were 5.5 and 5.5, 6.5 and 7.5, and 7.5 and 8.5 points for clinically meaningful improvement and deterioration, respectively.Conclusions: The minimal clinically important difference represents the smallest change in an outcome measure that is meaningful to patients. Our estimates for the Burke‐Fahn‐Marsden Dystonia Rating Scale and the 36‐Item Short‐Form Health Survey may allow more reliable judgment of the clinical relevance of different treatments for segmental and generalized isolated dystonia. © 2020 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

We propose the determination of phase-space distributions of optical fields by cascaded optical homodyning, where phase-randomized balanced homodyning is used for measuring the output photon-number statistics of an unbalanced homodyne detection scheme. The phase-space point of interest is controlled by the complex amplitude of the local oscillator and a universal sampling function is sufficient for mapping the measured quadrature statistics onto the phase-space distribution.