J. Adam Noah

Comparison of steps and energy expenditure assessment in adults of Fitbit Tracker and Ultra to the Actical and indirect calorimetry

Abstract Epidemic levels of inactivity are associated with chronic diseases and rising healthcare costs. To address this, accelerometers have been used to track levels of activity. The Fitbit and Fitbit Ultra are some of the newest commercially available accelerometers. The purpose of this study was to determine the reliability and validity of the Fitbit and Fitbit Ultra. Twenty-three subjects were fitted with two Fitbit and Fitbit Ultra accelerometers, two industry-standard accelerometers and an indirect calorimetry device. Subjects participated in 6-min bouts of treadmill walking, jogging and stair stepping. Results indicate the Fitbit and Fitbit Ultra are reliable and valid for activity monitoring (step counts) and determining energy expenditure while walking and jogging without an incline. The Fitbit and standard accelerometers under-estimated energy expenditure compared to indirect calorimetry for inclined activities. These data suggest the Fitbit and Fitbit Ultra are reliable and valid for monitoring over-ground energy expenditure.

Parietal and temporal activity during a multimodal dance video game: An fNIRS study

Using functional near infrared spectroscopy (fNIRS) we studied how playing a dance video game employs coordinated activation of sensory-motor integration centers of the superior parietal lobe (SPL) and superior temporal gyrus (STG). Subjects played a dance video game, in a block design with 30s of activity alternating with 30s of rest, while changes in oxy-hemoglobin (oxy-Hb) levels were continuously measured. The game was modified to compare difficult (4-arrow), simple (2-arrow), and stepping conditions. Oxy-Hb levels were greatest with increased task difficulty. The quick-onset, trapezoidal time-course increase in SPL oxy-Hb levels reflected the on-off neuronal response of spatial orienting and rhythmic motor timing that were required during the activity. Slow-onset, bell-shaped increases in oxy-Hb levels observed in STG suggested the gradually increasing load of directing multisensory information to downstream processing centers associated with motor behavior and control. Differences in temporal relationships of SPL and STG oxy-Hb concentration levels may reflect the functional roles of these brain structures during the task period. NIRS permits insights into temporal relationships of cortical hemodynamics during real motor tasks.

Frontotemporal oxyhemoglobin dynamics predict performance accuracy of dance simulation gameplay: Temporal characteristics of top-down and bottom-up cortical activities

We utilized the high temporal resolution of functional near-infrared spectroscopy to explore how sensory input (visual and rhythmic auditory cues) are processed in the cortical areas of multimodal integration to achieve coordinated motor output during unrestricted dance simulation gameplay. Using an open source clone of the dance simulation video game, Dance Dance Revolution, two cortical regions of interest were selected for study, the middle temporal gyrus (MTG) and the frontopolar cortex (FPC). We hypothesized that activity in the FPC would indicate top-down regulatory mechanisms of motor behavior; while that in the MTG would be sustained due to bottom-up integration of visual and auditory cues throughout the task. We also hypothesized that a correlation would exist between behavioral performance and the temporal patterns of the hemodynamic responses in these regions of interest. Results indicated that greater temporal accuracy of dance steps positively correlated with persistent activation of the MTG and with cumulative suppression of the FPC. When auditory cues were eliminated from the simulation, modifications in cortical responses were found depending on the gameplay performance. In the MTG, high-performance players showed an increase but low-performance players displayed a decrease in cumulative amount of the oxygenated hemoglobin response in the no music condition compared to that in the music condition. In the FPC, high-performance players showed relatively small variance in the activity regardless of the presence of auditory cues, while low-performance players showed larger differences in the activity between the no music and music conditions. These results suggest that the MTG plays an important role in the successful integration of visual and rhythmic cues and the FPC may work as top-down control to compensate for insufficient integrative ability of visual and rhythmic cues in the MTG. The relative relationships between these cortical areas indicated high- to low-performance levels when performing cued motor tasks. We propose that changes in these relationships can be monitored to gauge performance increases in motor learning and rehabilitation programs.

fMRI Validation of fNIRS Measurements During a Naturalistic Task

We present a method to compare brain activity recorded with near-infrared spectroscopy (fNIRS) in a dance video game task to that recorded in a reduced version of the task using fMRI (functional magnetic resonance imaging). Recently, it has been shown that fNIRS can accurately record functional brain activities equivalent to those concurrently recorded with functional magnetic resonance imaging for classic psychophysical tasks and simple finger tapping paradigms. However, an often quoted benefit of fNIRS is that the technique allows for studying neural mechanisms of complex, naturalistic behaviors that are not possible using the constrained environment of fMRI. Our goal was to extend the findings of previous studies that have shown high correlation between concurrently recorded fNIRS and fMRI signals to compare neural recordings obtained in fMRI procedures to those separately obtained in naturalistic fNIRS experiments. Specifically, we developed a modified version of the dance video game Dance Dance Revolution (DDR) to be compatible with both fMRI and fNIRS imaging procedures. In this methodology we explain the modifications to the software and hardware for compatibility with each technique as well as the scanning and calibration procedures used to obtain representative results. The results of the study show a task-related increase in oxyhemoglobin in both modalities and demonstrate that it is possible to replicate the findings of fMRI using fNIRS in a naturalistic task. This technique represents a methodology to compare fMRI imaging paradigms which utilize a reduced-world environment to fNIRS in closer approximation to naturalistic, full-body activities and behaviors. Further development of this technique may apply to neurodegenerative diseases, such as Parkinson’s disease, late states of dementia, or those with magnetic susceptibility which are contraindicated for fMRI scanning.

Frontal temporal and parietal systems synchronize within and across brains during live eye-to-eye contact

&NA; Human eye‐to‐eye contact is a primary source of social cues and communication. In spite of the biological significance of this interpersonal interaction, the underlying neural processes are not well‐understood. This knowledge gap, in part, reflects limitations of conventional neuroimaging methods, including solitary confinement in the bore of a scanner and minimal tolerance of head movement that constrain investigations of natural, two‐person interactions. However, these limitations are substantially resolved by recent technical developments in functional near‐infrared spectroscopy (fNIRS), a non‐invasive spectral absorbance technique that detects changes in blood oxygen levels in the brain by using surface‐mounted optical sensors. Functional NIRS is tolerant of limited head motion and enables simultaneous acquisitions of neural signals from two interacting partners in natural conditions. We employ fNIRS to advance a data‐driven theoretical framework for two‐person neuroscience motivated by the Interactive Brain Hypothesis which proposes that interpersonal interaction between individuals evokes neural mechanisms not engaged during solo, non‐interactive, behaviors. Within this context, two specific hypotheses related to eye‐to‐eye contact, functional specificity and functional synchrony, were tested. The functional specificity hypothesis proposes that eye‐to‐eye contact engages specialized, within‐brain, neural systems; and the functional synchrony hypothesis proposes that eye‐to‐eye contact engages specialized, across‐brain, neural processors that are synchronized between dyads. Signals acquired during eye‐to‐eye contact between partners (interactive condition) were compared to signals acquired during mutual gaze at the eyes of a picture‐face (non‐interactive condition). In accordance with the specificity hypothesis, responses during eye‐to‐eye contact were greater than eye‐to‐picture gaze for a left frontal cluster that included pars opercularis (associated with canonical language production functions known as Brocas region), pre‐ and supplementary motor cortices (associated with articulatory systems), as well as the subcentral area. This frontal cluster was also functionally connected to a cluster located in the left superior temporal gyrus (associated with canonical language receptive functions known as Wernickes region), primary somatosensory cortex, and the subcentral area. In accordance with the functional synchrony hypothesis, cross‐brain coherence during eye‐to‐eye contact relative to eye‐to‐picture gaze increased for signals originating within left superior temporal, middle temporal, and supramarginal gyri as well as the pre‐ and supplementary motor cortices of both interacting brains. These synchronous cross‐brain regions are also associated with known language functions, and were partner‐specific (i.e., disappeared with randomly assigned partners). Together, both within and across‐brain neural correlates of eye‐to‐eye contact included components of previously established productive and receptive language systems. These findings reveal a left frontal, temporal, and parietal long‐range network that mediates neural responses during eye‐to‐eye contact between dyads, and advance insight into elemental mechanisms of social and interpersonal interactions. Graphical abstract Figure. No caption available.

Activation of dorsolateral prefrontal cortex in a dual neuropsychological screening test: An fMRI approach

BackgroundThe Kana Pick-out Test (KPT), which uses Kana or Japanese symbols that represent syllables, requires parallel processing of discrete (pick-out) and continuous (reading) dual tasks. As a dual task, the KPT is thought to test working memory and executive function, particularly in the prefrontal cortex (PFC), and is widely used in Japan as a clinical screen for dementia. Nevertheless, there has been little neurological investigation into PFC activity during this test.MethodsWe used functional magnetic resonance imaging (fMRI) to evaluate changes in the blood oxygenation level-dependent (BOLD) signal in young healthy adults during performance of a computerized KPT dual task (comprised of reading comprehension and picking out vowels) and compared it to its single task components (reading or vowel pick-out alone).ResultsBehavioral performance of the KPT degraded compared to its single task components. Performance of the KPT markedly increased BOLD signal intensity in the PFC, and also activated sensorimotor, parietal association, and visual cortex areas. In conjunction analyses, bilateral BOLD signal in the dorsolateral PFC (Brodmanns areas 45, 46) was present only in the KPT.ConclusionsOur results support the central bottleneck theory and suggest that the dorsolateral PFC is an important mediator of neural activity for both short-term storage and executive processes. Quantitative evaluation of the KPT with fMRI in healthy adults is the first step towards understanding the effects of aging or cognitive impairment on KPT performance.

Physiological and psychophysiological responses to an exer-game training protocol

OBJECTIVES Exer-games and virtual reality offer alternative opportunities to provide neuro-rehabilitation and exercise that are fun. Our goal was to determine how effective they are in achieving motor learning goals and fitness benefits as players gain experience. DESIGN We employed a repeated measures design to determine changes in physical exertion and engagement with training. METHODS Fourteen healthy adults trained on the XBOX Kinect video game Dance Central using a skill-based protocol to examine changes in energy expenditure (EE), heart rate (HR), METs, limb movement, game proficiency, and player engagement in initial, post-training, and transfer-testing of a full-body dance exer-game. Data were analyzed using repeated measures analysis of variance, p<0.05. RESULTS Both EE, HR, and METs increased from initial (EE 4.89±1.35, HR 103±18, METs 4.25±0.72) to post-training (EE 5.92±1.25, HR 110±15, METs 5.05±0.75) and were greatest during transfer-testing (EE 6.34±1.35, HR 115±17, METs 5.42±0.88, p≤0.001). Proficiency, measured by game scores, also increased from initial to post-training and transfer-testing (p≤0.002). Limb movement and player engagement remained unchanged. CONCLUSIONS It is important to understand whether player physiological and psychophysiological responses change with continued game-play. Although Dance Central involves whole-body movement, physical exertion remained at moderate levels after training. As exer-game and virtual reality systems move from their initial novelty, research about how players react to continued involvement with a game can guide game developers to maintain a freshness through game progression that preserves the participants attentional focus, minimizes attrition and maintains a prescribed level of energy exertion.

Physiological and psychophysiological responses in experienced players while playing different dance exer-games

Display Omitted The perception of experienced players differs from novices.Greater physical exertion was related to higher engagement and game-flow.Problems with usability detracted from engagement and game-flow.With increased skill, perceived user control may matter more.Higher levels of interface embodiment did not reflect a more positive experience. As exer-game technology is increasingly integrated into workout and rehabilitation programs, it is important to understand how physical exertion, hedonics, and game usability experiences affect the knowledgeable player. In a repeated measures experiment, seven experienced players played five popular dance exer-games on separate days. Exertion was measured using indirect calorimetry. Hedonic experience was measured using questions about engagement and game-flow. Platform and software usability was determined by questionnaire and percent time spent in non-play activities (menu interfaces, software loading). Mean MET levels ranged from 4.26 to 9.18 during gameplay, depending on the game. Player engagement and game-flow were closely related to MET activity. Usability scores were closely related to time spent in non-play activities. Games with increased MET levels and higher usability scores were reflected in higher engagement and game-flow scores. Degree of interface embodiment did not affect these outcomes. Based on these results, problems in usability are barriers to engagement. Designing games that provide a balance of challenge, immersion, and engagement is a difficult task. These results demonstrate the importance of examining players of varying skill levels in order to fully understand the interaction of physical exertion, platform usability and player engagement.

Distributed Neural Activity Patterns during Human-to-Human Competition

Interpersonal interaction is the essence of human social behavior. However, conventional neuroimaging techniques have tended to focus on social cognition in single individuals rather than on dyads or groups. As a result, relatively little is understood about the neural events that underlie face-to-face interaction. We resolved some of the technical obstacles inherent in studying interaction using a novel imaging modality and aimed to identify neural mechanisms engaged both within and across brains in an ecologically valid instance of interpersonal competition. Functional near-infrared spectroscopy was utilized to simultaneously measure hemodynamic signals representing neural activity in pairs of subjects playing poker against each other (human–human condition) or against computer opponents (human–computer condition). Previous fMRI findings concerning single subjects confirm that neural areas recruited during social cognition paradigms are individually sensitive to human–human and human–computer conditions. However, it is not known whether face-to-face interactions between opponents can extend these findings. We hypothesize distributed effects due to live processing and specific variations in across-brain coherence not observable in single-subject paradigms. Angular gyrus (AG), a component of the temporal-parietal junction (TPJ) previously found to be sensitive to socially relevant cues, was selected as a seed to measure within-brain functional connectivity. Increased connectivity was confirmed between AG and bilateral dorsolateral prefrontal cortex (dlPFC) as well as a complex including the left subcentral area (SCA) and somatosensory cortex (SS) during interaction with a human opponent. These distributed findings were supported by contrast measures that indicated increased activity at the left dlPFC and frontopolar area that partially overlapped with the region showing increased functional connectivity with AG. Across-brain analyses of neural coherence between the players revealed synchrony between dlPFC and supramarginal gyrus (SMG) and SS in addition to synchrony between AG and the fusiform gyrus (FG) and SMG. These findings present the first evidence of a frontal-parietal neural complex including the TPJ, dlPFC, SCA, SS, and FG that is more active during human-to-human social cognition both within brains (functional connectivity) and across brains (across-brain coherence), supporting a model of functional integration of socially and strategically relevant information during live face-to-face competitive behaviors.

Neural correlates of conflict between gestures and words: A domain-specific role for a temporal-parietal complex

The interpretation of social cues is a fundamental function of human social behavior, and resolution of inconsistencies between spoken and gestural cues plays an important role in successful interactions. To gain insight into these underlying neural processes, we compared neural responses in a traditional color/word conflict task and to a gesture/word conflict task to test hypotheses of domain-general and domain-specific conflict resolution. In the gesture task, recorded spoken words (“yes” and “no”) were presented simultaneously with video recordings of actors performing one of the following affirmative or negative gestures: thumbs up, thumbs down, head nodding (up and down), or head shaking (side-to-side), thereby generating congruent and incongruent communication stimuli between gesture and words. Participants identified the communicative intent of the gestures as either positive or negative. In the color task, participants were presented the words “red” and “green” in either red or green font and were asked to identify the color of the letters. We observed a classic “Stroop” behavioral interference effect, with participants showing increased response time for incongruent trials relative to congruent ones for both the gesture and color tasks. Hemodynamic signals acquired using functional near-infrared spectroscopy (fNIRS) were increased in the right dorsolateral prefrontal cortex (DLPFC) for incongruent trials relative to congruent trials for both tasks consistent with a common, domain-general mechanism for detecting conflict. However, activity in the left DLPFC and frontal eye fields and the right temporal-parietal junction (TPJ), superior temporal gyrus (STG), supramarginal gyrus (SMG), and primary and auditory association cortices was greater for the gesture task than the color task. Thus, in addition to domain-general conflict processing mechanisms, as suggested by common engagement of right DLPFC, socially specialized neural modules localized to the left DLPFC and right TPJ including adjacent homologous receptive language areas were engaged when processing conflicting communications. These findings contribute to an emerging view of specialization within the TPJ and adjacent areas for interpretation of social cues and indicate a role for the region in processing social conflict.