Commit to your putting stroke: exploring the impact of quiet eye duration and neural activity on golf putting performance.

Introduction: There is a growing interest in characterizing the cognitive-motor processes that underlie superior performance in highly skilled athletes. The aim of this study was to explore neural markers of putting performance in highly skilled golfers by recording mobile EEG (electroencephalogram) during the pre-shot period. Methods: Twenty-eight right-handed participants (20 males) with a mean age of 24.2 years (± 6.4) and an average handicap of +1.7 (± 6.4) completed a testing session. Following the warm-up, participants completed 140 putts from a distance of 8ft (2.4m), with putts taken from 5 different positions. While putting, participants wore an eye tracker and a gel-based EEG system with 32 electrodes. Time and frequency domain features of the EEG signals were extracted to characterize Movement-Related Cortical Potentials (MRCP) and rhythmic modulations of neural activity in theta, alpha, sensorimotor and beta frequency bands associated with putting performance. Results: Eye-tracking data demonstrate that mean Quiet Eye durations are not a reliable marker of expertise as the same duration was found for both successful and unsuccessful putts. Following rigorous data processing data from 12 participants (8 males, mean age 21.6 years ± 5.4, average handicap +1.5 ± 4.4) were included in the EEG analysis. MRCP analysis revealed performance-based differences, with unsuccessful putts having a greater negative amplitude in comparison to successful putts. Time frequency analysis of the EEG data revealed that successful putts exhibit distinct neural activity profiles compared to unsuccessful ones. For successful putts, greater suppression of beta was present in the central region prior to the putt. By contrast, increased frontal theta power was present for unsuccessful putts immediately before the putt (consistent with hesitation and the need for motor plan adjustments prior to execution). Discussion: We propose that neural activity may provide plausible insights into the mechanisms behind why identical QE durations can lead to both success and failure. From an applied perspective, this study highlights the merits of a multi-measure approach to gain further insights into performance differences within highly skilled golfers. We discuss considerations for future research and solutions to address the challenges related to the complexities of collecting clean EEG signals within naturalistic sporting contexts.

Neural correlates of motor imagery and execution in real-world dynamic behavior: evidence for similarities and differences.

A large body of evidence shows that motor imagery and action execution behaviors result from overlapping neural substrates, even in the absence of overt movement during motor imagery. To date it is unclear how neural activations in motor imagery and execution compare for naturalistic whole-body movements, such as walking. Neuroimaging studies have not directly compared imagery and execution during dynamic walking movements. Here we recorded brain activation with mobile EEG during walking compared to during imagery of walking, with mental counting as a control condition. We asked 24 healthy participants to either walk six steps on a path, imagine taking six steps, or mentally count from one to six. We found beta and alpha power modulation during motor imagery resembling action execution patterns; a correspondence not found performing the control task of mental counting. Neural overlap occurred early in the execution and imagery walking actions, suggesting activation of shared action representations. Remarkably, a distinctive walking-related beta rebound occurred both during action execution and imagery at the end of the action suggesting that, like actual walking, motor imagery involves resetting or inhibition of motor processes. However, we also found that motor imagery elicits a distinct pattern of more distributed beta activity, especially at the beginning of the task. These results indicate that motor imagery and execution of naturalistic walking involve shared motor-cognitive activations, but that motor imagery requires additional cortical resources.

Investigating the Brain Mechanisms of Externally Cued Sit-to-Stand Movement in Parkinson's Disease.

BACKGROUND: One of the more challenging daily-life actions for Parkinson's disease patients is starting to stand from a sitting position. Parkinson's disease patients are known to have difficulty with self-initiated movements and benefit from external cues. However, the brain processes underlying external cueing as an aid remain unknown. The advent of mobile electroencephalography (EEG) now enables the investigation of these processes in dynamic sit-to-stand movements. OBJECTIVE: To identify cortical correlates of the mechanisms underlying auditory cued sit-to-stand movement in Parkinson's disease. METHODS: Twenty-two Parkinson's disease patients and 24 healthy age-matched participants performed self-initiated and externally cued sit-to-stand movements while cortical activity was recorded through 32-channel mobile EEG. RESULTS: Overall impaired integration of sensory and motor information can be seen in the Parkinson's disease patients exhibiting less modulation in the θ band during movement compared to healthy age-matched controls. How Parkinson's disease patients use external cueing of sit-to-stand movements can be seen in larger high ß power over sensorimotor brain areas compared to healthy controls, signaling sensory integration supporting the maintenance of motor output. This appears to require changes in cognitive processing to update the motor plan, reflected in frontal θ power increases in Parkinson's disease patients when cued. CONCLUSION: These findings provide the first neural evidence for why and how cueing improves motor function in sit-to-stand movement in Parkinson's disease. The Parkinson's disease patients' neural correlates indicate that cueing induces greater activation of motor cortical areas supporting the maintenance of a more stable motor output, but involves the use of cognitive resources to update the motor plan. © 2024 International Parkinson and Movement Disorder Society.

Characterizing neurocognitive impairments in Parkinson's disease with mobile EEG when walking and stepping over obstacles.

The neural correlates that help us understand the challenges that Parkinson's patients face when negotiating their environment remain under-researched. This deficit in knowledge reflects the methodological constraints of traditional neuroimaging techniques, which include the need to remain still. As a result, much of our understanding of motor disorders is still based on animal models. Daily life challenges such as tripping and falling over obstacles represent one of the main causes of hospitalization for individuals with Parkinson's disease. Here, we report the neural correlates of naturalistic ambulatory obstacle avoidance in Parkinson's disease patients using mobile EEG. We examined 14 medicated patients with Parkinson's disease and 17 neurotypical control participants. Brain activity was recorded while participants walked freely, and while they walked and adjusted their gait to step over expected obstacles (preset adjustment) or unexpected obstacles (online adjustment) displayed on the floor. EEG analysis revealed attenuated cortical activity in Parkinson's patients compared to neurotypical participants in theta (4-7 Hz) and beta (13-35 Hz) frequency bands. The theta power increase when planning an online adjustment to step over unexpected obstacles was reduced in Parkinson's patients compared to neurotypical participants, indicating impaired proactive cognitive control of walking that updates the online action plan when unexpected changes occur in the environment. Impaired action planning processes were further evident in Parkinson's disease patients' diminished beta power suppression when preparing motor adaptation to step over obstacles, regardless of the expectation manipulation, compared to when walking freely. In addition, deficits in reactive control mechanisms in Parkinson's disease compared to neurotypical participants were evident from an attenuated beta rebound signal after crossing an obstacle. Reduced modulation in the theta frequency band in the resetting phase across conditions also suggests a deficit in the evaluation of action outcomes in Parkinson's disease. Taken together, the neural markers of cognitive control of walking observed in Parkinson's disease reveal a pervasive deficit of motor-cognitive control, involving impairments in the proactive and reactive strategies used to avoid obstacles while walking. As such, this study identified neural markers of the motor deficits in Parkinson's disease and revealed patients' difficulties in adapting movements both before and after avoiding obstacles in their path.

The neural response is heightened when watching a person approaching compared to walking away: Evidence for dynamic social neuroscience.

The action observation network has been proposed to play a key role in predicting the action intentions (or goals) of others, thereby facilitating social interaction. Key information when interacting with others is whether someone (an agent) is moving towards or away from us, indicating whether we are likely to interact with the person. In addition, to determine the nature of a social interaction, we also need to take into consideration the distance of the agent relative to us as the observer. How this kind of information is processed within the brain is unknown, at least in part because prior studies have not involved live whole-body motion. Consequently, here we recorded mobile EEG in 18 healthy participants, assessing the neural response to the modulation of direction (walking towards or away) and distance (near vs. far distance) during the observation of an agent walking. We evaluated whether cortical alpha and beta oscillations were modulated differently by direction and distance during action observation. We found that alpha was only modulated by distance, with a stronger decrease of power when the agent was further away from the observer, regardless of direction. Critically, by contrast, beta was found to be modulated by both distance and direction, with a stronger decrease of power when the agent was near and facing the participant (walking towards) compared to when they were near but viewed from the back (walking away). Analysis revealed differences in both the timing and distribution of alpha and beta oscillations. We argue that these data suggest a full understanding of action observation requires a new dynamic neuroscience, investigating actual interactions between real people, in real world environments.

Motor Inhibition to Dangerous Objects: Electrophysiological Evidence for Task-dependent Aversive Affordances.

Previous work suggests that perception of an object automatically facilitates actions related to object grasping and manipulation. Recently, the notion of automaticity has been challenged by behavioral studies suggesting that dangerous objects elicit aversive affordances that interfere with encoding of an object's motor properties; however, related EEG studies have provided little support for these claims. We sought EEG evidence that would support the operation of an inhibitory mechanism that interferes with the motor encoding of dangerous objects, and we investigated whether such mechanism would be modulated by the perceived distance of an object and the goal of a given task. EEGs were recorded by 24 participants who passively perceived dangerous and neutral objects in their peripersonal, boundary, or extrapersonal space and performed either a reachability judgment task or a categorization task. Our results showed that greater attention, reflected in the visual P1 potential, was drawn by dangerous and reachable objects. Crucially, a frontal N2 potential, associated with motor inhibition, was larger for dangerous objects only when participants performed a reachability judgment task. Furthermore, a larger parietal P3b potential for dangerous objects indicated the greater difficulty in linking a dangerous object to the appropriate response, especially when it was located in the participants' extrapersonal space. Taken together, our results show that perception of dangerous objects elicits aversive affordances in a task-dependent way and provides evidence for the operation of a neural mechanism that does not code affordances of dangerous objects automatically, but rather on the basis of contextual information.

Mobile EEG reveals functionally dissociable dynamic processes supporting real-world ambulatory obstacle avoidance: Evidence for early proactive control.

The ability to safely negotiate the world on foot takes humans years to develop, reflecting the extensive cognitive demands associated with real-time planning and control of walking. Despite the importance of walking, methodological limitations mean that surprisingly little is known about the neural and cognitive processes that support ambulatory motor control. Here, we report mobile EEG data recorded from 32 healthy young adults during real-world ambulatory obstacle avoidance. Participants walked along a path while stepping over expected and unexpected obstacles projected on the floor, allowing us to capture the dynamic oscillatory response to changes in environmental demands. Compared to obstacle-free walking, time-frequency analysis of the EEG data revealed clear neural markers of proactive and reactive forms of movement control (occurring before and after crossing an obstacle), visible as increases in frontal theta and centro-parietal beta power respectively. Critically, the temporal profile of changes in frontal theta allowed us to arbitrate between early selection and late adaptation mechanisms of proactive control. Our data show that motor plans are updated as soon as an upcoming obstacle appears, rather than when the obstacle is reached. In addition, regardless of whether motor plans required updating, a clear beta rebound was present after obstacles were crossed, reflecting the resetting of the motor system. Overall, mobile EEG recorded during real-world walking provides novel insight into the cognitive and neural basis of dynamic motor control in humans, suggesting new routes to the monitoring and rehabilitation of motor disorders such as dyspraxia and Parkinson's disease.

Making sense of human interaction benefits from communicative cues.

We investigated whether communicative cues help observers to make sense of human interaction. We recorded EEG from an observer monitoring two individuals who were occasionally communicating with each other via either mutual eye contact and/or pointing gestures, and then jointly attending to the same object or attending to different objects that were placed on a table in front of them. The analyses were focussed on the processing of the interaction outcome (i.e. presence or absence of joint attention) and showed that its interpretation is a two-stage process, as reflected in the N300 and the N400 potentials. The N300 amplitude was reduced when the two individuals shared their focus of attention, which indicates the operation of a cognitive process that involves the relatively fast identification and evaluation of actor-object relationships. On the other hand, the N400 was insensitive to the sharing or distribution of the two individuals' attentional focus. Interestingly, the N400 was reduced when the interaction outcome was preceded either by mutual eye contact or by a perceived pointing gesture. This shows that observation of communication "opens up" the mind to a wider range of action possibilities and thereby helps to interpret unusual outcomes of social interactions.

Evidence for we-representations during joint action planning.

Do people engaged in joint action form action plans that specify joint outcomes at the group level? EEG was recorded from pairs of participants who performed coordinated actions that could result in different postural configurations. To isolate individual and joint action planning processes, a pre-cue specified in advance the individual actions and/or the joint configuration. Participants had 1200 ms to prepare their actions. Then a Go cue specified all action parameters and participants performed a synchronized action as quickly as possible. Action onsets were shorter when the pre-cue specified the joint configuration, regardless of whether individual action was also specified. EEG analyses showed that specifying joint action parameters in advance reduced ambiguity in a structured joint action plan (reflected in the decrease of the amplitude of the P600) and helped with representing action goals and interpersonal coordination patterns in sensorimotor brain areas (reflected in increased alpha/mu suppression and CNV amplitudes). These results provide clear evidence that joint action is driven not only by action plans that specify individual contributions, but also by action plans that specify joint action outcomes at the group level.

Concurrent Cortical Representations of Function- and Size-Related Object Affordances: An fMRI Study.

Previous work has shown that the perception of a graspable object may automatically potentiate actions that are tailored to specific action-related features of the object (e.g., its size) and may be related to its immediate grasping as well as to its long-term, functional use. We investigated the neural correlates of function- and size-related object affordances that may be concurrently potentiated by a graspable object. Participants were lying in a MR scanner holding a large switch in one hand and a small switch in the other hand. They passively attended a large or a small object with clearly separated functional and graspable end that was displayed centrally at an average angle of 45 degrees. Participants responded to the direction of an arrow that was overlaid on the object after a mean period of 1,000 ms after object onset and was pointing to the left or to the right with equal probability. Response times were shorter when the arrow pointed to the functional end of the object and when the responses were made with the switch that was congruent to the size of the perceived object. A clear distinction was found in the representation of function- and size-related affordances; the former was represented in the posterior parietal cortex and the latter in prefrontal, premotor, and primary sensorimotor cortices. We conclude that different aspects of object-directed actions may be automatically potentiated by individual object features and are represented in distinct brain areas.

Prioritization of arbitrary faces associated to self: An EEG study.

Behavioral and neuroimaging studies have demonstrated that people process preferentially self-related information such as an image of their own face. Furthermore, people rapidly incorporate stimuli into their self-representation even if these stimuli do not have an intrinsic relation to self. In the present study, we investigated the time course of the processes involved in preferential processing of self-related information. In two EEG experiments three unfamiliar faces were identified with verbal labels as either the participant, a friend, or a stranger. Afterwards, participants judged whether two stimuli presented in succession (ISI = 1500ms) matched. In experiment 1, faces were followed by verbal labels and in experiment 2, labels were followed by faces. Both experiments showed the same pattern of behavioral and electrophysiological results. If the first stimulus (face or label) was associated with self, reaction times were faster and the late frontal positivity following the first stimulus was more pronounced. The self-association of the second stimulus (label or face) did not affect response times. However, the central-parietal P3 following presentation of the second stimulus was more pronounced when the second stimulus was preceded by self-related first stimulus. These results indicate that even unfamiliar faces that are associated to self can activate a self-representation. Once the self-representation has been activated the processing of ensuing stimuli is facilitated, irrespective of whether they are associated with the self.

Evidence for dissociable effects of handedness and consistency of hand preference in allocation of attention and movement planning: An EEG investigation.

We studied the potentially dissociable effects of handedness and consistency of hand preference on allocation of attention and movement planning. EEG was recorded from an equally balanced group of left- and right-handed participants with consistent or inconsistent hand preference. The participants viewed photos of graspable objects and responded to the direction of an arrow that was overlaid on the object 1000ms after object onset. Attention-related ERPs elicited between 100 and 250ms after object onset were primarily modulated by the participants' handedness. On the other hand, ERPs related to late movement planning processes were modulated only by the consistency of hand preference. Our results suggest that the effects of the consistency of hand preference could be dissociated from those of handedness, the former influencing movement planning processes and the latter more related to allocation of attention.

It's not just my fault: Neural correlates of feedback processing in solo and joint action.

People often coordinate their actions with others' in pursuit of shared goals, yet little research has examined the neural processes by which people monitor whether shared goals have been achieved. The current study compared event-related potentials elicited by feedback indicating joint errors (resulting from two people's coordinated actions) and individual errors (resulting from one's own or another person's observed actions). Joint errors elicited a reduced feedback-related negativity (FRN) and P3a relative to own errors, and an enhanced FRN relative to observed errors. In contrast, P3b amplitudes did not differ between joint and individual errors. These findings indicate that producing errors together with a partner influences neural activity related to outcome evaluation but has less impact on activity related to the motivation to adapt future behaviour.

Perceiving objects by their function: An EEG study on feature saliency and prehensile affordances.

We examined the feature saliency and prehensile/motor affordance effects that are visually elicited by a graspable object's most salient features and graspable part, respectively. EEG was recorded from participants who attended a photo of an object, and responded to a left- or right-pointing arrow, which was overlaid on the object 1000 ms after object onset. Analysis of response times demonstrated the presence of a feature saliency effect. Lateralization of posterior alpha suppression showed that attention was initially directed to the object's (most salient) functional end. Pre-movement frontocentral beta suppression and the modulation of the P3 component showed that a response compatible to the functional end was activated before arrow onset. Moreover, lateralization of pre-movement posterior and central alpha suppression indicated a behaviorally masked affordance effect. This suggests that the two effects may occur independently, but without specific attention orienting instructions, the feature saliency effect dominates a potential prehensile affordance effect.

Attention allocation and task representation during joint action planning.

We investigated whether people take into account an interaction partner's attentional focus and whether they represent in advance their partner's part of the task when planning to engage in a synchronous joint action. The experiment involved two participants planning and performing joint actions (i.e., synchronously lifting and clinking glasses), unimanual individual actions (i.e., lifting and moving a glass as if clinking with another person), and bimanual individual actions. EEG was recorded from one of the participants. We employed a choice reaction paradigm where a visual cue indicated the type of action to be planned, followed 1.5 sec later by a visual go stimulus, prompting the participants to act. We studied attention allocation processes by examining two lateralized EEG components, namely the anterior directing attention negativity and the late directing attention positivity. Action planning processes were examined using the late contingent negative variation and the movement-related potential. The results show that early stages of joint action planning involve dividing attention between locations in space relevant for one's own part of the joint action and locations relevant for one's partner's part of the joint action. At later stages of joint action planning, participants represented in advance their partner's upcoming action in addition to their own action, although not at an effector-specific level. Our study provides electrophysiological evidence supporting the operation of attention sharing processes and predictive self/other action representation during the planning phase of a synchronous joint task.

Handedness consistency influences bimanual coordination: a behavioural and electrophysiological investigation.

Previous research has shown that handedness consistency might be a more important factor than direction of hand dominance in the performance of various cognitive and motor tasks. We investigated the effect of handedness consistency in bimanual coordination. We employed a task where participants had to respond to visual cues and perform symmetrical or asymmetrical bimanual movements towards cue-designated targets. Response and movement times were recorded in parallel with electroencephalography (EEG). Behavioural analyses showed that participants with inconsistent hand preference were equally fast in initiating symmetrical and asymmetrical bimanual movements, whereas participants with consistent hand preference were slower in initiating (the more demanding) asymmetrical movements. Moreover, the amplitudes of the Movement Related Potential and the suppression of the 10 Hz-mu rhythm were larger in participants with inconsistent hand preference over premotor and primary sensorimotor areas, although it is possible that the suppression of the mu rhythm may also depend on hand dominance. Our findings suggest that individuals with inconsistent hand preference have an advantage in the planning and organization of bimanual movements, which may not be related to the direction of their hand dominance.

History of interaction and task distribution modulate action simulation.

Recent work suggests that social interaction modulates the sensorimotor simulation of an observed action. Recording electroencephalograms during a triadic social interaction, we investigated the effects of two specific aspects of social interaction on action simulation: the recent history of interaction and the distribution of individual parts of a simple joint task between actors. Activation of sensorimotor areas was larger during observation of the individual action of an interaction partner compared to observation of the same action of a person performing only individual actions, unless this person had interacted with the observer in the recent past. In addition, it is likely that the participants simulated the action onset of the individual actions of their interaction partner, but only when their partner was the one who initiated the joint action. These results demonstrate that action simulation can be modulated by present and past interactions between the actor and the observer and by how a joint task is distributed between actors.

Monitoring individual and joint action outcomes in duet music performance.

We investigated whether people monitor the outcomes of their own and their partners' individual actions as well as the outcome of their combined actions when performing joint actions together. Pairs of pianists memorized both parts of a piano duet. Each pianist then performed one part while their partner performed the other; EEG was recorded from both. Auditory outcomes (pitches) associated with keystrokes produced by the pianists were occasionally altered in a way that either did or did not affect the joint auditory outcome (i.e., the harmony of a chord produced by the two pianists' combined pitches). Altered auditory outcomes elicited a feedback-related negativity whether they occurred in the pianist's own part or the partner's part, and whether they affected individual or joint action outcomes. Altered auditory outcomes also elicited a P300 whose amplitude was larger when the alteration affected the joint outcome compared with individual outcomes and when the alteration affected the pianist's own part compared with the partner's part. Thus, musicians engaged in joint actions monitor their own and their partner's actions as well as their combined action outcomes, while at the same time maintaining a distinction between their own and others' actions and between individual and joint outcomes.

Favouritism in the motor system: social interaction modulates action simulation.

The ability to anticipate others' actions is crucial for social interaction. It has been shown that this ability relies on motor areas of the human brain that are not only active during action execution and action observation, but also during anticipation of another person's action. Recording electroencephalograms during a triadic social interaction, we assessed whether activation of motor areas pertaining to the human mirror-neuron system prior to action observation depends on the social relationship between the actor and the observer. Anticipatory motor activation was stronger when participants expected an interaction partner to perform a particular action than when they anticipated that the same action would be performed by a third person they did not interact with. These results demonstrate that social interaction modulates action simulation.