A Pilot Study of the Convergent and Discriminant Validity of the Dutch Version of the Parametric Go/No-Go Task.

BACKGROUND: The parametric go/no-go (PGNG) task is a computerized task that is designed to measure cognitive flexibility, response inhibition, and working memory. The PGNG task has been shown to measure core executive functions (EFs) in a psychometrically sound, brief, and ecologically valid manner. OBJECTIVE: To analyze the psychometric properties of the Dutch version of the PGNG task in a convenience sample of nonclinical adults. METHOD: The sample consisted of 74 highly educated adults, with an average age of 36 years. Forty-two participants completed test battery A to investigate the task's convergent validity; 36 participants completed test battery B to investigate the task's discriminant validity. The results were analyzed using a repeated-measures ANOVA, Friedman's test, paired-samples t test, and correlation analyses. RESULTS: Level 3 of the PGNG task places increased demands on sustained attention, response inhibition, and set-shifting. Several moderate correlations between level 3 and a complex EFs measure supported the convergent validity of this level of the PGNG task. The convergent validity of levels 1 and 2 was not supported. No significant correlations were found between PGNG levels and non-EF tests, supporting discriminant validity. CONCLUSION: Our study included a rather homogenous sample of highly educated participants, which might explain the convergent validity of level 3 of the Dutch version of the PGNG task. Hence, to overcome these potentially confounding factors, the Dutch version of the PGNG task should be investigated in a larger and more heterogeneous population in terms of age and educational level.

Functional and clinical outcomes of FMRI-based neurofeedback training in patients with alcohol dependence: a pilot study.

Identifying treatment options for patients with alcohol dependence is challenging. This study investigates the application of real-time functional MRI (rtfMRI) neurofeedback (NF) to foster resistance towards craving-related neural activation in alcohol dependence. We report a double-blind, placebo-controlled rtfMRI study with three NF sessions using alcohol-associated cues as an add-on therapy to the standard treatment. Fifty-two patients (45 male; 7 female) diagnosed with alcohol dependence were recruited in Munich, Germany. RtfMRI data were acquired in three sessions and clinical abstinence was evaluated 3 months after the last NF session. Before the NF training, BOLD responses and clinical data did not differ between groups, apart from anger and impulsiveness. During NF training, BOLD responses of the active group were decreased in medial frontal areas/caudate nucleus, and increased, e.g. in the cuneus/precuneus and occipital cortex. Within the active group, the down-regulation of neuronal responses was more pronounced in patients who remained abstinent for at least 3 months after the intervention compared to patients with a relapse. As BOLD responses were comparable between groups before the NF training, functional variations during NF cannot be attributed to preexisting distinctions. We could not demonstrate that rtfMRI as an add-on treatment in patients with alcohol dependence leads to clinically superior abstinence for the active NF group after 3 months. However, the study provides evidence for a targeted modulation of addiction-associated brain responses in alcohol dependence using rtfMRI.

Correlations Between the DMN and the Smoking Cessation Outcome of a Real-Time fMRI Neurofeedback Supported Exploratory Therapy Approach: Descriptive Statistics on Tobacco-Dependent Patients.

The aim of this study was to explore the potential of default mode network (DMN) functional connectivity for predicting the success of smoking cessation in patients with tobacco dependence in the context of a real-time function al MRI (RT-fMRI) neurofeedback (NF) supported therapy.Fifty-four tobacco-dependent patients underwent three RT-fMRI-NF sessions including resting-state functional connectivity (RSFC) runs over a period of 4 weeks during professionally assisted smoking cessation. Patients were randomized into two groups that performed either active NF of an addiction-related brain region or sham NF. After preprocessing, the RSFC baseline data were statistically evaluated using seed-based ROI (SBA) approaches taking into account the smoking status of patients after 3 months (abstinence/relapse).The results of the real study group showed a widespread functional connectivity in the relapse subgroup (n = 10) exceeding the DMN template and mainly low correlations and anticorrelations in the within-seed analysis. In contrast, the connectivity pattern of the abstinence subgroup (n = 8) primarily contained the core DMN in the seed-to-whole-brain analysis and a left lateralized correlation pattern in the within-seed analysis. Calculated Multi-Subject Dictionary Learning (MSDL) matrices showed anticorrelations between DMN regions and salience regions in the abstinence group. Concerning the sham group, results of the relapse subgroup (n = 4) and the abstinence subgroup (n = 6) showed similar trends only in the within-seed analysis.In the setting of a RT-fMRI-NF-assisted therapy, a widespread intrinsic DMN connectivity and a low negative coupling between the DMN and the salience network (SN) in patients with tobacco dependency during early withdrawal may be useful as an early indicator of later therapy nonresponse.

Effects of binaural and monaural beat stimulation on attention and EEG.

Nowadays a popular technique to improve mood and cognition is auditory beat stimulation (ABS), which is thought to induce a frequency-following response of brainwaves. The main types of ABS are monaural beats (MB) and binaural beats (BB). BB involves the presentation of a specific frequency to one ear and another frequency to the other ear which may induce neural entrainment. A difference between the frequencies of 40 Hz is assumed to improve cognition. The present study examined the effect of 40 Hz binaural beats (BB) and monaural beats (MB) on attention and electroencephalography (EEG). A total of 25 first-year psychology students (11 males, 14 females) performed a Flanker task while EEG was recorded during the 5 min-presentation of pink noise (PN), MB and BB. With respect to attention, as measured by the Flanker task, the number of false responses in the BB condition was smaller than that in the PN condition while the number of false responses in the MB condition was larger as compared to the PN condition. As there was no association of BB with a consistent increase in absolute 40 or 45 Hz power compared to PN or MB, EEG recordings could not confirm the hypothesized neural entrainment in the brain. Overall, the current findings show that listening to 40 Hz BB improves attention but do not show the occurrence of neural entrainment. Future research is recommended to include a larger sample, to use a broader cognitive test battery and to present auditory beats with a longer duration.

The Effects of Binaural and Monoaural Beat Stimulation on Cognitive Functioning in Subjects with Different Levels of Emotionality.

Today, binaural and monaural beats are offered over the Internet or by mental health institutes to improve wellbeing or cognitive functioning. This improvement is explained by the assumption that the brain adapts its brainwave frequency to the frequency of the auditory beat. The present study examined the effects of binaural and monaural beat stimulation on attention and working memory in high and low emotional participants. A group of 24 participants (16 females, 8 males) between 19 and 31 years old (M = 22.33, SD = 3.42) performed a Flanker task to measure attention and a Klingberg task to measure working memory while listening to white noise (WN), 40 Hz gamma binaural beat (BB) and 40 Hz gamma monaural beat (MB). Speed of performance on all three levels of difficulty of the Flanker attention task was faster under the BB and MB condition than under WN. No differences were found between BB and MB conditions. With respect to the quality of performance on the Flanker attention task and the Klingberg working memory task no significant differences under the WN, MB, and BB condition were found. Finally, as participants with low or high emotionality did not respond differently to BB and MB under any of the conditions, effects of BB and MB seem similar in high and low emotional participants. The present study supports the notion that faster attention processing may equally be attributed to the influence of BB and MB. Further research is recommended to gain more insight in the role of factors such as duration of stimulation of BB and MB, frequency range, most appropriate carrier tones, and the role of personality traits.