No tDCS Augmented Working Memory Training Benefit in Undergraduates Rewarded with Course Credit

Background: The goal of working memory (WM) training is to expand capacity of this executive function. Transcranial direct current stimulation (tDCS) paired with WM training is more consistent than either alone. We have reported that tDCS targeting frontal and/or parietal regions enhanced theta phase locking, reduced alpha power, and strengthened theta-gamma phase amplitude coupling. Objective: To determine whether tDCS to frontal or parietal sites optimized WM training gains we pre-registered a tDCS-WM training study. Methods: 80 undergraduates were randomly assigned to one of four anodal tDCS montages: frontal (F4), parietal (P4), alternating (P4-F4), and sham (P4 or F4). Participants completed 5-training sessions over one week and returned for follow-up testing after 30 days of no-contact. Results: No group showed significant improvement in trained or transfer task performance at the end of training nor at follow-up. Conclusions: This null finding marks a failure to replicate in undergraduates training benefits observed in graduate students. We argue that motivation is essential to elicit improved performance in training protocols

The NeuroDante Project: Neurometric measurements of participant’s reaction to literary auditory stimuli from dante’s “divina commedia”

Neurodante. Progetto di analisi neurometrica di alcuni brani della Commedi

What's working memory to do with it? A case study on teenagers

Effective teachers recognise that as their students grow, the way in which their students learn changes. This is related to different developmental stages of the brain that occur as a child becomes an adult. This article discusses the concept of working memory and explores how working memory changes during adolescence. The research presented here used an approach to measuring working memory using electroencephalography (EEG) to examine differences in the capacity for using working memory between older and younger adolescent students at a school in Western Australia. The differences in the neurological processes related to working memory in adolescents of different ages were examined with implications for teachers in secondary schools

What's working memory to do with it? A case study on teenagers

Effective teachers recognise that as their students grow, the way in which their students learn changes. This is related to different developmental stages of the brain that occur as a child becomes an adult. This article discusses the concept of working memory and explores how working memory changes during adolescence. The research presented here used an approach to measuring working memory using electroencephalography (EEG) to examine differences in the capacity for using working memory between older and younger adolescent students at a school in Western Australia. The differences in the neurological processes related to working memory in adolescents of different ages were examined with implications for teachers in secondary schools

Theta phase synchronization between the human hippocampus and prefrontal cortex increases during encoding of unexpected information: A case study

Events that violate predictions are thought to not only modulate activity within the hippocampus and PFC but also enhance communication between the two regions. Scalp and intracranial EEG studies have shown that oscillations in the theta frequency band are enhanced during processing of contextually unexpected information. Some theories suggest that the hippocampus and PFC interact during processing of unexpected events, and it is possible that theta oscillations may mediate these interactions. Here, we had the rare opportunity to conduct simultaneous electrophysiological recordings from the human hippocampus and PFC from two patients undergoing presurgical evaluation for pharmacoresistant epilepsy. Recordings were conducted during a task that involved encoding of contextually expected and unexpected visual stimuli. Across both patients, hippocampal–prefrontal theta phase synchronization was significantly higher during encoding of contextually unexpected study items, relative to contextually expected study items. Furthermore, the hippocampal–prefrontal theta phase synchronization was larger for contextually unexpected items that were later remembered compared with later forgotten items. Moreover, we did not find increased theta synchronization between the PFC and rhinal cortex, suggesting that the observed effects were specific to prefrontal–hippocampal interactions. Our findings are consistent with the idea that theta oscillations orchestrate communication between the hippocampus and PFC in support of enhanced encoding of contextually deviant information

Cognición, respuesta electroencefalográfica y su relación con la variabilidad de la frecuencia cardíaca

Introducción. La corteza cerebral frontal tiene una mayor actividad teta durante procesos cognitivos de observación y aprendizaje.Objetivo. Establecer la relación entre actividad electroencefalográfica orbitofrontal y sistema nervioso autónomo en procesos cognitivos.Materiales y métodos. 20 hombres y 19 mujeres con edad promedio de 21.2 (±2.32) años fueron evaluados mediante electroencefalografía (EGG) FP1-T3, FP2-T4 y electrocardiografía (EKG, del alemán elektrokardiogramm) para determinar frecuencia cardíaca (HR, del inglés heart rate) y variabilidad de la frecuencia cardíaca (HRV, del inglés heart rate variability). La evaluación tuvo cinco fases: reposo, observación, memoria, concentración y juego. Las señales de EGG y EKG fueron analizadas en el dominio de la frecuencia usando la transformada rápida de Fourier (FFT, del inglés fast Fourier transform). Las diferencias por etapa entre las variables se establecieron con el uso de ANOVA de dos vías.Resultados. Comparado con el reposo, se observó en todas las fases incremento de la actividad teta del EGG (p0.01), aumento en la baja frecuencia LF (p0.01) y la HR (p0.01) y disminución de la alta frecuencia HF (p0.01). Además, hubo una correlación inversa entre la actividad teta y la potencia de HF (r=-0.86).Conclusiones. Los datos mostraron una reducción de la actividad parasimpática y un aumento de la actividad simpática asociado a actividad teta de la corteza orbitofrontal, mediante una conexión con el núcleo central de la amígdala.Introduction: The frontal cortex has a greater theta activity during cognitive observation and learning processes.Objective: To establish the relation between orbitofrontal electroencephalographic activity and the autonomic nervous system in cognitive processes.Materials and methods: 20 men and 19 women with a mean age of 21.2 (±2.32) were evaluated by electroencephalography (EGG) FP1-T3, FP2-T4 and electrocardiography (ECG) to determine heart rate (HR) and heart rate variability (HRV). The evaluation was made in five phases during rest, observation, memory, concentration and playing conditions. EGG and ecg signals were analyzed in the frequency domain using the Fast Fourier Transform (FFT). The differences between the variables found during each phase were established through a two-way ANOVA.Results: When compared to rest conditions, all phases showed an increase of theta activity of the EGG (p 0.01), as well as of the low frequencies LF (p 0.01) and HR (p 0.01), and a decrease in the high frequency HF (P 0.01). In addition, there was an inverse correlation between theta activity and HF power (r=-0.86).Conclusions: The data showed a reduction in parasympathetic activity and an increased sympathetic activity associated with theta activity in the orbitofrontal cortex, using a connection with the central nucleus of the amygdala

Beta oscillations following performance feedback predict subsequent recall of task-relevant information

Reward delivery in reinforcement learning tasks elicits increased beta power in the human EEG over frontal areas of the scalp but it is unclear whether these 20-30 Hz oscillations directly facilitate reward learning. We previously proposed that frontal beta is not specific to reward processing but rather reflects the role of prefrontal cortex in maintaining and transferring task-related information to other brain areas. To test this proposal, we had subjects perform a reinforcement learning task followed by a memory recall task in which subjects were asked to recall stimuli associated either with reward feedback (Reward Recall condition) or error feedback (Error Recall condition). We trained a classifier on post-feedback beta power in the Reward Recall condition to discriminate trials associated with reward feedback from those associated with error feedback and then tested the classifier on post-feedback beta power in the Error Recall condition. Crucially, the model classified error-related beta in the Error Recall condition as reward-related. The model also predicted stimulus recall from post-feedback beta power irrespective of feedback valence and task condition. These results indicate that post-feedback beta power is not specific to reward processing but rather reflects a more general task-related process

Alpha/beta and theta modulation during behavioral impulsivity

Impulsivity is widely understood as a detriment of rational decision-making, but the neural mechanisms that guide impulsive behavior are not well understood. Neural oscillations, as a method of neuronal interregional communication, may be associated with the lack of motor inhibition found in impulsive behavior. In the present experiment, we use EEG to observe oscillatory changes related to behavioral impulsivity during the 5-Choice Serial Reaction Time Task (5-CSRTT). We hypothesized decreased alpha/beta activity, which would represent a lack of inhibition, and increased theta activity, which would represent increased cognitive effort, preceding an impulsive response. Although we did observe the expected increase in theta power, we also found increased alpha/beta power preceding impulsive responses, thus highlighting how each of these frequency bands may have roles in behavioral impulsivity. These findings were robust across several regions of interest, include middle prefrontal cortex, left motor region, and visual cortex. Interestingly, the theta power was localized to a relatively posterior region, likely due to low cognitive demand of the task. These changes in neural oscillations present one potential mechanism behind behavioral impulsivity.Bachelor of Scienc