Applications of Alpha Neurofeedback Processes for Enhanced Mental Manipulation of Unfamiliar Molecular and Spatial Structures.

This study explores a novel approach to enhancing cognitive proficiency by targeting neural mechanisms that facilitate science and math learning, especially mental rotation. The study specifically examines the relationship between upper alpha intensity and mental rotation skills. Although prior neurofeedback research for increasing upper alpha highlights this correlation, mostly with familiar objects, novel chemistry and math learning prompts envisioning unfamiliar objects which question the persistence of this correlation. This study revisits the upper alpha and mental rotation relationship in the context of unfamiliar objects with a single neurofeedback session and examines the efficiency of manual and automatic neurofeedback protocols. Results will provide a basis for integrating neurofeedback protocols into learning applications for enhanced learning. Our study encompassed three cohorts: Group 1 experienced an automatic neurofeedback protocol, Group 2 received a manual neurofeedback protocol, and the control group had no neurofeedback intervention. The experimental phases involved EEG measurement of individual upper alpha (frequency of maximal power + 2 Hz) intensity, mental rotation tasks featuring geometric and unfamiliar molecular stimuli, one neurofeedback session for applicable groups, post-treatment upper alpha level assessments, and a mental rotation retest. The neurofeedback groups exhibited increased levels of upper alpha power, which was correlated with improved response time in mental rotation, regardless of stimulus type, compared to the control group. Both neurofeedback protocols achieved comparable results. This study advocates integrating neurofeedback into learning software for optimal learning experiences, highlighting a single session's efficacy and the substantial neurofeedback protocol's impact in enhancing upper alpha oscillations.

Shared mechanisms underlie mental imagery and motor planning.

Many studies have associated mental imagery with motor control mechanisms by showing mutually active brain areas and functions, as well as similar temporal patterns of imagining and executing the same motor actions. One of the main conjectured mutual mechanisms is the Cerebellar forward-model, commonly believed to generate sensory predictions as part of both motor control and mental imagery processes. Nevertheless, trials to associate one's overall individual mental and motor capacities have shown only mild and inconsistent correlations, hence challenging the mutual mechanism assumption. We hypothesized that one cause to this inconsistency is the forward-model's dominance in the motor-planning stage only when adapting to novel sensorimotor environments, while the inverse-model is gradually taking the lead along the adaptation, and therefore biasing most attempts to measure motor-mental overlapping functions and correlate these measurements under regular circumstances. Our current study aimed to tackle and explore this gap using immersive virtual embodiment, by applying an experience of a fundamental sensorimotor conflict, thereby manipulating the sensory prediction mechanism, and presumably forcing an increased involvement of the forward-model in the motor planning stage throughout the experiment. In the study, two groups of subjects (n = 48) performed mental and manual rotation within an immersive, motion-captured, virtual reality environment, while the sensorimotor dynamics of only the test group were altered by physical-virtual speed re-mapping making the virtual hand move twice as fast as the physical hand controlling it. Individual mental imagery capacities were assessed before and after three blocks of manual-rotation, where motor planning durations were measured as the time until motion onset. The results show that virtual sensorimotor alteration extremely increases the correlation of mental imagery and motor planning (r = 0.9, p < .0001) and leads to higher mental imagery performance improvement following the physical blocks. We particularly show that virtual embodiment manipulation affects the motor planning stage to change and functionally overlap with imagery mechanisms, rather than the other way around, which supports our conjecture of an increased sensory-prediction forward-model involvement. Our results shed new light on the embodied nature of mental imagery, support the view of the predictive forward-model as a key mechanism mutually underlying motor control and imagery, and suggest virtual sensorimotor alteration as a novel methodology to increase physical-mental convergence. These findings also suggest the applicability of using existing motion-tracked virtual environments for continuous cognitive evaluation and treatment, through kinematic analysis of ongoing natural motor behaviors.

Neural Signatures of Interface Errors in Remote Agent Manipulation.

The manipulation of remote agents such as robotic arms in remote surgery or in BCI-wheelchair control are prone to errors. Some of these are related to user intent misclassification or other interface system errors, which lead to an incorrect movement. Here we focused on errors originating from unpredicted interface movements violating user intent and producing sensory conflicts. In addition, we examined effects of incongruent/congruent sensory stimuli induced by interface errors, focusing on haptic and visual cues in the system. The overarching goal was to identify the prototypical patterns of electroencephalogram (EEG) error signals associated with two types of interface errors rising when the visual and proprioceptive feedback are congruent or incongruent. For purposes of comparison validity, both types of errors were recorded in the same 3D virtual game environment. The comparison of congruent and incongruent interface errors revealed significant and marginally significant differences in EEG potentials with respect to profile, latencies, scalp distribution and sources. Different EEG time-frequency combinations had high power content. Incongruence between visual and proprioceptive feedback in interface errors not only elicited distinct EEG signal characteristics, but also produced a marginally significant Stroop effect. Incongruency in visuo-haptic feedback modalities cause a delayed user response. This effect is of major importance for the design of controlling interfaces and can provide designers with crucial information when aiming to control human response time.

Consensus on the reporting and experimental design of clinical and cognitive-behavioural neurofeedback studies (CRED-nf checklist).

Neurofeedback has begun to attract the attention and scrutiny of the scientific and medical mainstream. Here, neurofeedback researchers present a consensus-derived checklist that aims to improve the reporting and experimental design standards in the field.

How Long Is Too Long: An Individual Time-Window for Motor Planning.

Human motor response time (RT) is determined by the matureness of the preceding neural motor planning process. In the current study, we characterize the temporal boundaries required for the motor planning process, and its impact on the overall motor RT. In particular, we contrasted short and long planning times by measuring the resulting differences in motor RTs, in an attempt to find whether an optimal planning time for minimal RT exists. Using a "Timed Response" paradigm, we presented participants with varying planning intervals prior to a requested motor response and studied their effect on the timing of initiation of the following movement. We found that, as expected, reaction time shortens as more planning time is provided, yet only until reaching a minimal RT, after which additional planning time increases the motor RT, thus creating a U-shaped behavioral function. Furthermore, since the minimal RT was found to be an individual characteristic, we suggest that there is an individual time window for motor planning.

Author Correction: Evidence for deficient motor planning in ADHD.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

Components of Motor Deficiencies in ADHD and Possible Interventions.

There is a growing body of evidence pointing at several types of motor abnormalities found in attention-deficit/hyperactivity disorder (ADHD). In this article we review findings stemming from different paradigms, and suggest an interweaving approach to the different stages involved in the motor regulation process. We start by reviewing various aspects of motor abnormalities found in ADHD and related brain mechanisms. Then, we classify reported motor impairments associated with ADHD, into four classes of motor stages: Attention to the task, motion preparation, motion execution and motion monitoring. Motor abnormalities and corresponding neural activations are analyzed in the context of each of the four identified motor patterns, along with the interactions among them and with other systems. Given the specifications and models of the role of the four motor impairments in ADHD, we ask what treatments correspond to the identified motor impairments. We analyze therapeutic interventions targeting motor difficulties most commonly experienced among individuals with ADHD; first, Neurofeedback training and EMG-biofeedback. As some of the identified components of attention, planning and monitoring have been shown to be linked to abnormal oscillation patterns in the brain, we examine neurofeedback interventions aimed to address these types of oscillations: Theta/beta frequency training and SCP neurofeedback targeted at elevating the CNV component. Additionally we discuss EMG-Biofeedback interventions targeted at feedback on motor activity. Further we review physical activity and motor interventions aimed at improving motor difficulties, associated with ADHD. These kinds of interventions are shown to be helpful not only in aspects of physical ability, but also in enhancing cognition and executive functioning.

Neural Correlates of User-initiated Motor Success and Failure - A Brain-Computer Interface Perspective.

Any motor action is, by nature, potentially accompanied by human errors. In order to facilitate development of error-tailored Brain-Computer Interface (BCI) correction systems, we focused on internal, human-initiated errors, and investigated EEG correlates of user outcome successes and errors during a continuous 3D virtual tennis game against a computer player. We used a multisensory, 3D, highly immersive environment. Missing and repelling the tennis ball were considered, as 'error' (miss) and 'success' (repel). Unlike most previous studies, where the environment "encouraged" the participant to perform a mistake, here errors happened naturally, resulting from motor-perceptual-cognitive processes of incorrect estimation of the ball kinematics, and can be regarded as user internal, self-initiated errors. Results show distinct and well-defined Event-Related Potentials (ERPs), embedded in the ongoing EEG, that differ across conditions by waveforms, scalp signal distribution maps, source estimation results (sLORETA) and time-frequency patterns, establishing a series of typical features that allow valid discrimination between user internal outcome success and error. The significant delay in latency between positive peaks of error- and success-related ERPs, suggests a cross-talk between top-down and bottom-up processing, represented by an outcome recognition process, in the context of the game world. Success-related ERPs had a central scalp distribution, while error-related ERPs were centro-parietal. The unique characteristics and sharp differences between EEG correlates of error/success provide the crucial components for an improved BCI system. The features of the EEG waveform can be used to detect user action outcome, to be fed into the BCI correction system.

Theta Neurofeedback Effects on Motor Memory Consolidation and Performance Accuracy: An Apparent Paradox?

Previous studies have shown that theta neurofeedback enhances motor memory consolidation on an easy-to-learn finger-tapping task. However, the simplicity of the finger-tapping task precludes evaluating the putative effects of elevated theta on performance accuracy. Mastering a motor sequence is classically assumed to entail faster performance with fewer errors. The speed-accuracy tradeoff (SAT) principle states that as action speed increases, motor performance accuracy decreases. The current study investigated whether theta neurofeedback could improve both performance speed and performance accuracy, or would only enhance performance speed at the cost of reduced accuracy. A more complex task was used to study the effects of parietal elevated theta on 45 healthy volunteers The findings confirmed previous results on the effects of theta neurofeedback on memory consolidation. In contrast to the two control groups, in the theta-neurofeedback group the speed-accuracy tradeoff was reversed. The speed-accuracy tradeoff patterns only stabilized after a night's sleep implying enhancement in terms of both speed and accuracy.

Monitoring brain potentials to guide neurorehabilitation of tracking impairments.

Motor impairments come in different forms. One class of motor impairments, relates to accuracy of tracking a moving object, as, for instance, when chasing in an attempt to catch it. Here we look at neural signals associated with errors in tracking, and the implications for brain-computer-interfaces that target impairment-tailored rehabilitation. As a starting point, we characterized EEG signals evoked by tracking errors during continuous natural motion, in healthy participants. Participants played a virtual 3D, ecologically valid haptic tennis game, and had to track a moving tennis ball in order to hit and send the ball towards the opponent's court. Sudden changes in the motion of the tennis ball elicited error related potentials. These were characterized by a negative peak at 135 msec and two positive peaks at 211 and 336 msec. The negative peak had a parietal scalp distribution, and the positive had a centro-frontal distribution. sLORETA source estimation for the peaks suggested brain activity in the somatosensory, motor, visual and anterior cingulate cortex. Implications are double: changes in the error potential characteristics provide an assessment strategy for rehabilitation; and the identified error potential can be used in the Brain computer interface feedback loop for tailored rehabilitation. Taken together, these results provide a methodology of rehabilitation systems specifically tailored to the unique impairment.

Evidence for deficient motor planning in ADHD.

We compare motor planning mechanisms of ADHD and control subjects based on their effect on later observed kinematic characteristics. We monitor hand movement following planning conditions that differ in preparation time, and evaluate the differences across conditions and participants with/without ADHD. Our findings show that when there is sufficient planning time, people without ADHD seem to have a motor plan ready, and immediately initiate a planned movement after a 'GO' cue, with a bell shaped velocity profile. When planning time is not sufficient, they start the movement in a delayed time, possibly indicating that they needed to complete a movement plan. However, people with ADHD, did not start movement immediately after the cue, even when provided with a long preparation time, possibly indicating that even for this planning interval they did not have a motion plan ready. The movement was not only delayed, its velocity profile was not bell shaped and had several peaks. We further found differences between control and ADHD participants in the velocity profile, variability and jitter of movements. Our results suggest that ADHD motion characteristics, are associated with an immature motor plan. Based on the results we propose a paradigm to evaluate deficiencies in motor planning.

I act, therefore I err: EEG correlates of success and failure in a virtual throwing game.

What are the neural responses to success and failure in a throwing task? To answer this question, we compared Event Related Potentials (ERPs) correlated with success and failure during a highly-ecological-virtual game. Participants played a tennis-like game in an immersive 3D virtual world, against a computer player, by controlling a virtual tennis racket with a force feedback robotic arm. Results showed that success, i.e. hitting the target, and failure, by missing the target, evoked ERP's that differ by peak, latencies, scalp signal distributions, sLORETA source estimation, and time-frequency patterns. The success related grand averaged ERP at the Cz electrode, had two peaks - a negative peak at 244ms and a positive peak at 12ms, prior to the actual successful hit, suggesting a possible process of prediction of success. The grand averaged ERP correlated with failure at Cz, had two peaks, a negative peak at about 107ms and a positive peak at about 311ms post failure. These results suggest different top-down and bottom-up loops for success and failure, which seem to be rooted in the spatial arrangement of the virtual game. Although the latency of the latter is consistent with the error related potentials reported in the literature, the characteristic is unique to this specific error, and differ significantly from other error related potentials in the same environment. These results further provide a basis for EEG based assessment and prediction of user's successful or erroneous movements, and design of the feedback loop in EEG based Brain-Computer Interfaces.

EEG-based cognitive load of processing events in 3D virtual worlds is lower than processing events in 2D displays.

Interacting with 2D displays, such as computer screens, smartphones, and TV, is currently a part of our daily routine; however, our visual system is built for processing 3D worlds. We examined the cognitive load associated with a simple and a complex task of learning paper-folding (origami) by observing 2D or stereoscopic 3D displays. While connected to an electroencephalogram (EEG) system, participants watched a 2D video of an instructor demonstrating the paper-folding tasks, followed by a stereoscopic 3D projection of the same instructor (a digital avatar) illustrating identical tasks. We recorded the power of alpha and theta oscillations and calculated the cognitive load index (CLI) as the ratio of the average power of frontal theta (Fz.) and parietal alpha (Pz). The results showed a significantly higher cognitive load index associated with processing the 2D projection as compared to the 3D projection; additionally, changes in the average theta Fz power were larger for the 2D conditions as compared to the 3D conditions, while alpha average Pz power values were similar for 2D and 3D conditions for the less complex task and higher in the 3D state for the more complex task. The cognitive load index was lower for the easier task and higher for the more complex task in 2D and 3D. In addition, participants with lower spatial abilities benefited more from the 3D compared to the 2D display. These findings have implications for understanding cognitive processing associated with 2D and 3D worlds and for employing stereoscopic 3D technology over 2D displays in designing emerging virtual and augmented reality applications.

Recognition of the semantics and kinematics of gestures: Neural responses to "what" and "how"?

The extensive use of gestures for human-human communication, independently of culture and language, suggests an underlying universal neural mechanism for gesture recognition. The mirror neuron system (MNS) is known to respond to observed human actions, and overlaps with self-action. The minimal cues needed for activation of the MNS for gesture recognition, facial expressions and bodily dynamics, is not yet defined. Using LED-point representations of gestures, we compared two types of brain activations: 1) in response to human recognizable vs non-recognizable motion and 2) in response to human vs non-human motion. Our preliminary results show that parts of the MNS respond only to human kinematics, and not to nonhuman kinematics, suggesting that the brain has a mechanism of discriminating human from nonhuman motion, even if the pattern of motion is meaningless, but still follows biological motion patterns. This implies that mechanisms of learning-mimicking, empathy and emotional communication, are possibly constrained by biological motion patterns. We then suggest a two-tier-model of human-bodily-communication: (1) recognition of human biological kinematics; (2) recognition of meaning. Implications are both theoretical (understanding the underlying mechanism for action recognition) and applicative (in digital graphical social representations, motion should be reasonably biological to generate the same emotional and mimicking automatic mechanisms as in face-to-face social interactions).

Prediction of attendance at fitness center: a comparison between the theory of planned behavior, the social cognitive theory, and the physical activity maintenance theory.

In the processes of physical activity (PA) maintenance specific predictors are effective, which differ from other stages of PA development. Recently, Physical Activity Maintenance Theory (PAMT) was specifically developed for prediction of PA maintenance. The aim of the present study was to evaluate the predictability of the future behavior by the PAMT and compare it with the Theory of Planned Behavior (TPB) and Social Cognitive Theory (SCT). Participation rate in a fitness center was observed for 101 college students (53 female) aged between 19 and 32 years (M = 23.6; SD = 2.9) over 20 weeks using a magnetic card. In order to predict the pattern of participation TPB, SCT and PAMT were used. A latent class zero-inflated Poisson growth curve analysis identified two participation patterns: regular attenders and intermittent exercisers. SCT showed the highest predictive power followed by PAMT and TPB. Impeding aspects as life stress and barriers were the strongest predictors suggesting that overcoming barriers might be an important aspect for working out on a regular basis. Self-efficacy, perceived behavioral control, and social support could also significantly differentiate between the participation patterns.

Family health climate scale (FHC-scale): development and validation.

BACKGROUND: The family environment is important for explaining individual health behaviour. While previous research mostly focused on influences among family members and dyadic interactions (parent-child), the purpose of this study was to develop a new measure, the Family Health Climate Scale (FHC-Scale), using a family-based approach. The FHC is an attribute of the whole family and describes an aspect of the family environment that is related to health and health behaviour. Specifically, a questionnaire measuring the FHC (a) for nutrition (FHC-NU) and (b) for activity behaviour (FHC-PA) was developed and validated. METHODS: In Study 1 (N=787) the FHC scales were refined and validated. The sample was randomly divided into two subsamples. With random sample I exploratory factor analyses were conducted and items were selected according to their psychometric quality. In a second step, confirmatory factor analyses were conducted using the random sample II. In Study 2 (N=210 parental couples) the construct validity was tested by correlating the FHC to self-determined motivation of healthy eating and physical activity as well as the families' food environment and joint physical activities. RESULTS: Exploratory factor analyses with random sample I (Study 1) revealed a four (FHC-NU) and a three (FHC-PA) factor model. These models were cross-validated with random sample II and demonstrated an acceptable fit [FHC-PA: χ(2)=222.69, df=74, p<.01; χ(2)/df=3.01; CFI=.96; SRMR=.04; RMSEA=.07, CI .06/.08; FHC-NU: χ(2)=278.30, df=113, p<.01, χ(2)/df=2.46, CFI=.96; SRMR=.04; RMSEA=.06, CI .05/.07]. The perception of FHC correlated (p<.01) with the intrinsic motivation of healthy eating (r=.42) and physical activity (r=.56). Moreover, parental perceptions of FHC-NU correlated with household soft drink availability (r=-.31) and perceptions of FHC-PA with the frequency of joint physical activities with the child (r=.51). These patterns were found on the intraindividual and interindividual level. CONCLUSIONS: Two valid instruments measuring the FHC within families were developed. The use of different informants' ratings demonstrated that the FHC is a family level variable. The results confirm the high relevance of the FHC for individuals' health behaviour. The FHC and the measurement instruments are useful for examining health-related aspects of the family environment.

Perspectives and possible applications of the rubber hand and virtual hand illusion in non-invasive rehabilitation: technological improvements and their consequences.

This review introduces theoretical aspects of the rubber hand illusion (RHI) and virtual hand illusion (VHI), and discusses their possible clinical applications. It also presents technical improvements regarding the realization of the RHI and VHI and their relation to rehabilitation issues. There is presently little evidence describing the value of the RHI and VHI as indices in the diagnosis or treatment of different pathologies, likely because of a lack of standardization in reporting the results of RHI and VHI studies. In contrast, a new emerging "out-of-body illusion" appears to be an interesting new approach; however, as in RHI and VHI, there are additional consequences regarding its application in clinical settings because of its technological demands. This review considers the acceptance of technology and the realization of immersion/presence in the context of virtual rehabilitation.