A cross-sectional survey of internet use among university students.

The last 2 decades have seen an increase in the number of reports of excessive internet use. Therefore, this study aimed to examine internet use among university students to gain more insight into the novel phenomenon of addictive internet use (AIU). Data were collected by the means of an online questionnaire sent to 4391 students. Approximately 10% of the 4391 students could be included in the statistical analysis. Of those 483 students, almost all (99.2%) used the internet, and a quarter (24.8%) showed AIU. The students used the internet mostly for information searches, random browsing, social networking, and online shopping; however, AIU was seen most often in the areas of social networking, random browsing, information searches, gaming, and pornography. One in four of the respondents showed addictive behavior in at least one area of internet use. Students with AIU in the area of random browsing were significantly less far advanced in their studies than those without AIU, and well-being was significantly poorer across AIU groups than in those who did not show AIU. The study confirms the importance of AIU, as reflected in the high prevalence of AIU among the students and the significantly lower level of well-being in those with AIU. Undifferentiated consideration of AIU does not do justice to its various facets, and future research should consider all areas of internet use, with the aim to increase understanding of the underlying mechanisms of AIU and develop more differentiated treatment approaches.

Single-session transcranial direct current stimulation induces enduring enhancement of visual processing speed in patients with major depression.

Attentional deficits are considered key cognitive symptoms in major depressive disorder (MDD) arising from abnormal activation patterns within dorsolateral prefrontal cortex (dlPFC) alertness networks. Altering these activity patterns with transcranial direct current stimulation (tDCS) might thus ameliorate alertness-dependent cognitive deficits in MDD patients. In a double-blind, randomized, sham-controlled study, we investigated the effect of a single session of anodal tDCS (2 mA) applied to the left dlPFC on different parameters of visual attention based on Bundesen's theory of visual attention (Psychol Rev 97(4):523-547, 1990) in a group of 20 patients with MDD and a control group of 20 healthy participants. The parametric attention assessment took place before, immediately after and 24 h after tDCS intervention. It revealed a selective impairment in visual processing speed as a primary functional deficit in MDD at baseline assessment. Furthermore, a significant stimulation condition × time point interaction showed that verum tDCS over the left dlPFC resulted in a processing speed enhancement 24 h post-stimulation in MDD patients. In healthy control participants, we did not find similar tDCS-induced effects. Our results suggest that even a single session of tDCS over the dlPFC can induce enduring neurocognitive benefits that indicate an amelioration of cortical under-arousal in MDD patients in a time frame beyond that of immediate, excitability increases that are directly induced by the current.

Event-Related Potentials Are Associated With Unexpected Gain and Loss: Using a Gambling Paradigm.

OBJECTIVE: Previous neuroimaging studies have described altered activity in brain areas associated with reward processing following reward or punishment. This study examines the extent to which feedback-based experience of gain and loss is associated with electrophysiological correlates. METHODS: Twenty-nine healthy participants used a gambling task that focused on actual nonpredictable gains and losses. During the task, an electroencephalography recording was performed in order to assess reward processing. Event-related potentials were analyzed when participants were receiving gain/loss feedback. RESULTS: Event-related potentials revealed higher feedback-related negativity for both overall gain and loss compared with a neutral condition in fronto-centro-parietal electrodes. P3 potentials were significantly increased for high gains/losses compared to neutral and small gains/losses. CONCLUSION: These results indicate that the paradigm is suitable to evoke specific patterns of reward-related electrophysiological responses. The wavelet analysis showed that electroencephalography frequency variations depended on the amount of gains/losses. SIGNIFICANCE: This gambling paradigm is appropriate to measure aspects of feedback processing and could help analyze disease-specific alterations of the reward system in patients.