Feeding behaviour in term and preterm infants

Recent advances in technology have resulted in more preterm infants being kept alive. These increases in survival rates have, however, been met with a parallel increase in morbidity rates. My thesis has been concerned with monitoring the feeding behaviour of preterm infants born at a low gestation and birthweight, who are at risk of developing neurological problems. These infants often have difficulty co-ordinating the different mechanisms of feeding, namely sucking, swallowing and breathing. Particular attention was paid to sucking, viewing it as a precocious motor skill. By using a new dimension of the tau theory of motor control, namely the intrinsic tau-pacemaker model, normal sucking control was established by examining the intra oral sucking pressures of twelve term newborns The results supported a strong coupling between the tau of the pressure generated inside the mouth and an intrinsic tau-pacemaker. Six preterm infants born at less than 30 weeks gestational age and classified as neurologically at risk, were also tested from when they started bottle feeding, and for a period of four weeks thereafter. Their sucking pressures were analysed in the same way, and were individually compared to the standard set by the newborn terms. Large deviations from term norms were hypothesised to be indicative of neurological abnormalities. Irregularities in sucking control were found, but as expected, the extent of the variation differed between infants. Follow up movement assessments, when four of the infants were greater than six months corrected age, were performed by a physiotherapist. The physiotherapist's assessment of motor development at this stage appeared to reflect the findings obtained for the infants' sucking control. Breathing measurements were also recorded, and modulations in the pattern during feeding were noted. Again a newborn term pattern was established, and preterm infants were compared. As before, all the preterm infants tested had differing degrees of respiratory difficulty. Breathing problems were evident from significantly lower levels of oxygen concentration in the blood, and a significant difference in the timing and depth of the breaths during the sucking and pause periods of feeding. In conclusion an analysis of feeding behaviour appears to present a wealth of information about the neurological and physiological development of very preterm infants. vi

Editorial: Sound, Music, and Movement in Parkinson’s Disease

International audienceAs a final collection, this special issue allows us to disseminate state-of-the-art knowledge on the functional deterioration of motor control and present novel behavioral interventions that aim to alleviate symptoms in PD. In particular, we are interested in forms of movement therapy that are sustainable, focused on improving quality of life in the long term and feasible even where resources are scarce. Our parallel aim was to push the Frontiers of our understanding to see how sensory information can afford and shape movement facilitation in PD and how our knowledge can feed into the design of tailored rehabilitation programs. This is why experts from the fields of auditory stimulation, neuroimaging, motor control, and dance therapy were invited to engage in a dialog on the current and future management of PD, suggesting possible new routes for therapy while outlining the limitations of our current scientific understanding. The end result of this international effort is presented in this e-book

A Wii Bit of Fun: A Novel Platform to Deliver Effective Balance Training to Older Adults

BACKGROUND: Falls and fall-related injuries are symptomatic of an aging population. This study aimed to design, develop, and deliver a novel method of balance training, using an interactive game-based system to promote engagement, with the inclusion of older adults at both high and low risk of experiencing a fall.STUDY DESIGN: Eighty-two older adults (65 years of age and older) were recruited from sheltered accommodation and local activity groups. Forty volunteers were randomly selected and received 5 weeks of balance game training (5 males, 35 females; mean, 77.18 ± 6.59 years), whereas the remaining control participants recorded levels of physical activity (20 males, 22 females; mean, 76.62 ± 7.28 years). The effect of balance game training was measured on levels of functional balance and balance confidence in individuals with and without quantifiable balance impairments.RESULTS: Balance game training had a significant effect on levels of functional balance and balance confidence (P Peer reviewedFinal Published versio

Shoaling promotes place over response learning but does not facilitate individual learning of that strategy in zebrafish (Danio rerio)

Abstract Background Flexible spatial memory, such as “place” learning, is an important adaptation to assist successful foraging and to avoid predation and is thought to be more adaptive than response learning which requires a consistent start point. Place learning has been found in many taxonomic groups, including a number of species of fish. Surprisingly, a recent study has shown that zebrafish (Danio rerio), a common species used in cognitive research, demonstrated no significant preference for the adoption of either a place or a response strategy during a plus maze task. That being said, a growing body of research has been looking at how group living influences navigational decisions in animals. This study aims to see how zebrafish, a shoaling species, differ in their ability to perform a maze task when learning in a shoal and as an individual. Results Results suggest that shoals of zebrafish are able to learn to perform the spatial memory task in a significantly shorter time than individual fish and appear to show place learning when tested from a novel start point. Interestingly, zebrafish who were trained first in a shoal but were then tested as individuals, did not show the same level of consistency in their choice of navigation strategy. Conclusions These findings suggest that shoaling influences navigation behaviour, resulting in faster group learning and convergence on one spatial memory strategy, but does not facilitate the transfer of the strategy learned to individuals within the shoal

Expert players accurately detect an opponent's movement intentions through sound alone

Sounds offer a rich source of information about events taking place in our physical and social environment. However, outside the domains of speech and music, little is known about whether humans can recognize and act upon the intentions of another agent's actions detected through auditory information alone. In this study we assessed whether intention can be inferred from the sound an action makes, and in turn, whether this information can be used to prospectively guide movement. In 2 experiments experienced and novice basketball players had to virtually intercept an attacker by listening to audio recordings of that player's movements. In the first experiment participants had to move a slider, while in the second one their body, to block the perceived passage of the attacker as they would in a real basketball game. Combinations of deceptive and nondeceptive movements were used to see if novice and/or experienced listeners could perceive the attacker's intentions through sound alone. We showed that basketball players were able to more accurately predict final running direction compared to nonplayers, particularly in the second experiment when the interceptive action was more basketball specific. We suggest that athletes present better action anticipation by being able to pick up and use the relevant kinematic features of deceptive movement from event-related sounds alone. This result suggests that action intention can be perceived through the sound a movement makes and that the ability to determine another person's action intention from the information conveyed through sound is honed through practice. (PsycINFO Database Recor

Bending It Like Beckham: How to Visually Fool the Goalkeeper

As bending free-kicks becomes the norm in modern day soccer, implications for goalkeepers have largely been ignored. Although it has been reported that poor sensitivity to visual acceleration makes it harder for expert goalkeepers to perceptually judge where the curved free-kicks will cross the goal line, it is unknown how this affects the goalkeeper's actual movements.Here, an in-depth analysis of goalkeepers' hand movements in immersive, interactive virtual reality shows that they do not fully account for spin-induced lateral ball acceleration. Hand movements were found to be biased in the direction of initial ball heading, and for curved free-kicks this resulted in biases in a direction opposite to those necessary to save the free-kick. These movement errors result in less time to cover a now greater distance to stop the ball entering the goal. These and other details of the interceptive behaviour are explained using a simple mathematical model which shows how the goalkeeper controls his movements online with respect to the ball's current heading direction. Furthermore our results and model suggest how visual landmarks, such as the goalposts in this instance, may constrain the extent of the movement biases.While it has previously been shown that humans can internalize the effects of gravitational acceleration, these results show that it is much more difficult for goalkeepers to account for spin-induced visual acceleration, which varies from situation to situation. The limited sensitivity of the human visual system for detecting acceleration, suggests that curved free-kicks are an important goal-scoring opportunity in the game of soccer

A goalkeeper’s performance in stopping free kicks reduces when the defensive wall blocks their initial view of the ball

Free kicks are an important goal scoring opportunity in football. It is an unwritten rule that the goalkeeper places a wall of defending players with the aim of making scoring harder for the attacking team. However, the defensive wall can occlude the movements of the kicker, as well as the initial part of the ball trajectory. Research on one-handed catching suggests that a ball coming into view later will likely delay movement initiation and possibly affect performance. Here, we used virtual reality to investigate the effect of the visual occlusion of the initial ball trajectory by the wall on the performance of naïve participants and skilled goalkeepers. We showed that movements were initiated significantly later when the wall was present, but not by the same amount as the duration of occlusion (~200ms, versus a movement delay of ~70-90ms); movements were thus initiated sooner after the ball came into view, based on less accumulated information. For both naïve participants and skilled goalkeepers this delayed initiation significantly affected performance (i.e., 3.6cm and 1.5cm larger spatial hand error, respectively, not differing significantly between the groups). These performance reductions were significantly larger for shorter flight times, reaching increased spatial errors of 4.5cm and 2.8cm for both groups, respectively. Further analyses showed that the wall-induced performance reduction did not differ significantly between free kicks with and without sideward curve. The wall influenced early movement biases, but only for free kicks with curve in the same direction as the required movement; these biases were away from the final ball position, thus hampering performance. Our results cannot suggest an all-out removal of the wall-this study only considered one potential downside-but should motivate goalkeepers to continuously evaluate whether placing a wall is their best option. This seems most pertinent when facing expert free kick takers for whom the wall does not act as a block (i.e., whose kicks consistently scale the wall)

Detecting Deception in Movement: The Case of the Side-Step in Rugby

Although coordinated patterns of body movement can be used to communicate action intention, they can also be used to deceive. Often known as deceptive movements, these unpredictable patterns of body movement can give a competitive advantage to an attacker when trying to outwit a defender. In this particular study, we immersed novice and expert rugby players in an interactive virtual rugby environment to understand how the dynamics of deceptive body movement influence a defending player’s decisions about how and when to act. When asked to judge final running direction, expert players who were found to tune into prospective tau-based information specified in the dynamics of ‘honest’ movement signals (Centre of Mass), performed significantly better than novices who tuned into the dynamics of ‘deceptive’ movement signals (upper trunk yaw and out-foot placement) (p<.001). These findings were further corroborated in a second experiment where players were able to move as if to intercept or ‘tackle’ the virtual attacker. An analysis of action responses showed that experts waited significantly longer before initiating movement (p<.001). By waiting longer and picking up more information that would inform about future running direction these experts made significantly fewer errors (p<.05). In this paper we not only present a mathematical model that describes how deception in body-based movement is detected, but we also show how perceptual expertise is manifested in action expertise. We conclude that being able to tune into the ‘honest’ information specifying true running action intention gives a strong competitive advantage