Theta EEG neurofeedback promotes early consolidation of real life-like episodic memory.

Theta oscillations are believed to coordinate neuronal activity related to human cognition, especially for memory functions. Theta power during learning and retrieval has been found to correlate with memory performance success. Additionally, up-regulating theta oscillations during a post-encoding epoch crucial for memory consolidation was previously shown to benefit long-term memory for acquired motor sequences, pictures, and object-location associations. However, it remains to be determined whether such effects would be found for more ecological aspects of long-term episodic memory. Therefore, the current study assessed neurofeedback-based theta upregulation effects on movie memory. After viewing a 15-minute silent, narrative movie, participants engaged in neurofeedback-based theta/beta up-regulation, neurofeedback beta/theta up-regulation as an active control condition, or an unrelated passive control task. Memory was tested three times: once immediately after watching the movie (as baseline); 24 hours thereafter; and once again 1 week later. Memory performance 1 week after encoding was significantly enhanced in the theta/beta up-regulation group compared with the other groups. Additionally, changes in neurofeedback theta/beta ratio from baseline EEG recordings correlated with long-term memory gains in retrieving the movie's content. These findings highlight the relationship between post-learning theta oscillations and the consolidation of episodic memory for a naturalistic event.

Social Expectations are Primarily Rooted in Reciprocity: An Investigation of Fairness, Cooperation, and Trustworthiness.

Social expectations guide people's evaluations of others' behaviors, but the origins of these expectations remain unclear. It is traditionally thought that people's expectations depend on their past observations of others' behavior, and people harshly judge atypical behavior. Here, we considered that social expectations are also influenced by a drive for reciprocity, and people evaluate others' actions by reflecting on their own decisions. To compare these views, we performed four studies. Study 1 used an Ultimatum Game task where participants alternated Responder and Proposer roles. Modeling participants' expectations suggested they evaluated the fairness of received offers via comparisons to their own offers. Study 2 replicated these findings and showed that observing selfish behavior (lowball offers) only promoted acceptance of selfishness if observers started acting selfishly themselves. Study 3 generalized the findings, demonstrating that they also arise in the Public Goods Game, emerge cross-culturally, and apply to antisocial punishment whereby selfish players punish generosity. Finally, Study 4 introduced the Trust Game and showed that participants trusted players who reciprocated their behavior, even if it was selfish, as much as they trusted generous players. Overall, this research shows that social expectations and evaluations are rooted in drives for reciprocity. This carries theoretical implications, speaking to a parallel in the mechanisms driving both decision-making and social evaluations, along with practical importance for understanding and promoting cooperation.

Direct feedback and social conformity promote behavioral change via mechanisms indexed by centroparietal positivity: Electrophysiological evidence from a role-swapping ultimatum game.

Our behavior is shaped by multiple factors, including direct feedback (seeing the outcomes of our past actions) and social observation (in part, via a drive to conform to other peoples' behaviors). However, it remains unclear how these two processes are linked in the context of behavioral change. This is important to investigate, as behavioral change is associated with distinct neural correlates that reflect specific aspects of processing, such as information integration and rule updating. To clarify whether these processes characterize both direct learning and conformity, we elicited the two within the same task, using a role-swapping version of the Ultimatum Game-a fairness paradigm where subjects decide how to share a pot of money with other players-while electroencephalography (EEG) data were recorded. Behavioral results showed that subjects decided how to divide the pot based on both direct feedback (seeing whether their past proposals were accepted or rejected) and social observation (copying the splits that others just proposed). Converging EEG evidence revealed that increased centroparietal positivity (P2, P3b, and late positivity) indexed behavioral changes motivated by direct feedback and those motivated by drives to conform. However, exploratory analyses also suggest that these two motivating factors may also be dissociable, and that frontal midline theta oscillations may predict behavioral changes linked to direct feedback but not conformity. Overall, this study provides novel electrophysiological evidence regarding the different forms of behavioral change. These findings are also relevant for understanding the mechanisms of social information processing that underlie successful cooperation.

Chornobyl, radiation, neural tube defects, and microcephaly.

Pregnant women residing in areas impacted by the Chornobyl ionizing radiation of the Rivne Province in Ukraine have persistent higher levels of incorporated cesium-137. In these areas the neural tube defects and microcephaly rates are significantly higher than in areas with lower maternal cesium-137 incorporated levels. In two Rivne counties with populations proximal to nuclear power plants the rates of neural tube defects and microcephaly are the highest in the province. The neural tube defects rates in Rivne are persistently among the highest in Europe.

Elevated congenital anomaly rates and incorporated cesium-137 in the Polissia region of Ukraine.

BACKGROUND: Investigations soon after the 1986 Chornobyl (Chernobyl in Russian) accident of exposed populations residing elsewhere in Europe led government and international agencies to conclude that exposures to cesium-137 (Cs-137) were not teratogenic. Our observations of elevated population rates of neural tube defects (NTDs) and microcephaly and microphthalmia (M/M) in the Rivne Province in Ukraine, which were among the highest in Europe, prompted this follow-up investigation inclusive of whole-body counts (WBCs) of Cs-137 among ambulatory patients and pregnant women residing in Polissia, the most polluted region in Rivne. METHODS: Yearly (2000-2012) population rates of NTDs and M/M and WBC patterns of ambulatory patients (2001-2010) and pregnant women (2011-2013) in Polissia and non-Polissia regions of Rivne were analyzed. RESULTS: The NTD and M/M population rates in Rivne remain elevated and are statistically significantly higher in Polissia than in non-Polissia. The WBCs among residents in Polissia are statistically significantly higher than among those from non-Polissia. CONCLUSION: NTD and M/M rates are highest in the Polissia region of Rivne and are among the highest in Europe. In Polissia, the WBCs of Cs-137 are above officially set permissible upper limits. The results are based on aggregate data of NTDs and M/Ms and average WBC values. Further investigations of causality of the high rates of NTDs and M/Ms are needed and urgent strengthening policies and implementations to reduce exposures to teratogens, in particular radioactive nuclides and alcohol, and consumption of folic acid supplements are indicated.