Temporal pattern of pre-shooting psycho-physiological states in elite athletes: A probabilistic approach

Objective

The IZOF-based probabilistic approach provides a methodology to study within-individual patterns of a performer's states. So far, the time course of physiological data before performance have not been investigated within the probabilistic methodology framework. The purpose of this study was to examine the value of the probabilistic approach in the assessment of the time course of physiological indicators of arousal/activation and vigilance during the period preceding the shot, in comparison with the performance-based method.

Design

Longitudinal assessment of psycho-physiological data and performance outcomes was conducted on eight elite pistol shooters in a controlled setting.

Methods

Each participant performed 60 air-pistol shots in 2 sessions. Skin conductance level and cardiac activity were recorded. Affective states intensity was evaluated on a modified 11-point Borg scale. Affect, HR and SC level were evaluated with a Performance-based approach and a Probabilistic method, and results compared at an individual level.

Results

Findings showed the higher effectiveness of the probabilistic method to analyse physiological parameters (skin conductance and heart rate) and to describe the physiological mechanisms associated with shooters’ performance.

Conclusions

The probabilistic method better discerned the contribution of arousal/activation and vigilance to optimal and non-optimal performance in elite shooters, thereby providing a sharper representation of the temporal pattern of performers' states before shooting. From an applied perspective, we believe that the probabilistic approach can help athletes become aware of the subtle variations occurring in their psychophysical states during the preparatory period preceding the shot and not only at the moment of shot release.     

The effects of attentional training on physiological stress recovery after induced social threat

Abstract

Social stress has been related to both physiological and psychological responses. The recovery of stress is influenced by the way environmental information is processed, i.e., what information is attended to and how it is interpreted. The present study investigated the effect of attention modification training on physiological stress recovery following induced stress. A group of applicants preparing for a job interview were randomly allocated to an attention training condition versus a control condition. Afterwards, they were asked to give an artificial job interview to a real life jury while being videotaped. Participants in both conditions showed decreased heart rate variability during the job interview, which indicates an overall physiological stress response. However, during a 30-minute follow-up period after the training, indices of heart rate variability showed improved stress recovery only in the attention training condition. Attentional training is proposed as a promising strategy to prevent enduring stress reactions.     

Risk Factors for the Occurrence of Child Abuse and Neglect

SUMMARY

A large, nationally representative database of child abuse and neglect cases was analyzed to identify demographic risk factors for the occurrence of different types of abuse and neglect. The analyses used the data collected in the second National Incidence Study of Child Abuse and Neglect (the NIS-2) concerning children who were harmed by abuse or neglect. Multiple-factor logistic models were developed to identify risk factors for the occurrence of abuse or neglect in six categories of maltreatment: physical abuse, sexual abuse, emotional maltreatment, physical neglect, educational neglect, and multiple maltreatment. A key finding was that children in families with incomes under $15,000 per year were at far greater risk in every category of maltreatment. Also, older children were generally at greater risk in every category, and risk was related to family structure, family size, child's sex and race/ethnicity, and metropolitan status of the county. However, these relationships applied to only certain types of abuse or neglect or took different forms in different maltreatment categories. Interactions among risk factors were the rule rather than the exception. Findings emphasize the need for better coordination between human services and income support services to families. The results imply that risk assessment would be appreciably advanced by going beyond simple matrix approaches that independently consider different factors by developing assessment models that include interactions between different risk factors.     

Moving the Arm at Different Rates: Slow Movements are Avoided

Qualitative and quantitative changes characterize locomotion and rhythmic interlimb coordination at different speeds. Legs and hands do not move more or less quickly; they also adopt different relative coordination patterns. In the present article, the authors asked whether similar transitions occur for unimanual hand movements when speed is slowed below the preferred speed. Participants moved a handheld dowel back and forth between 2 large circular targets in time with a metronome at periods between 370 ms and 1667 ms. The authors analyzed the kinematics of participants’ movements at each period and found that proportional dwell time and number of peaks in the velocity profile increased as driving periods increased. Path lengths and peak velocities remained relatively constant for driving periods exceeding 800 ms. Participants made only gradual changes to their movement parameters, so that they went from a continuous mode to a more discrete mode of behavior for longer driving periods. Thus, unlike for rhythmic bimanual movements or locomotory patterns, there are quantitative but no clear qualitative changes for unimanual movements. The results suggest that participants tried to move close to their preferred tempo at different rates, and that they avoided moving slowly.     

Near-term fetal response to maternal spoken voice

Knowledge about prenatal learning has been largely predicated on the observation that newborns appear to recognize the maternal voice. Few studies have examined the process underlying this phenomenon; that is, whether and how the fetus responds to maternal voice in situ. Fetal heart rate and motor activity were recorded at 36 weeks gestation (n = 69) while pregnant women read aloud from a neutral passage. Compared to a baseline period, fetuses responded with a decrease in motor activity in the 10 s following onset of maternal speech and a trend level decelerative heart rate response, consistent with an orienting response. Subsequent analyses revealed that the fetal response was modified by both maternal and fetal factors. Fetuses of women who were previously awake and talking (n = 40) showed an orienting response to onset of maternal reading aloud, while fetuses of mothers who had previously been resting and silent (n = 29) responded with elevated heart rate and increased movement. The magnitude of the fetal response was further dependent on baseline fetal heart rate variability such that largest response was demonstrated by fetuses with low variability of mothers who were previously resting and silent. Results indicate that fetal responsivity is affected by both maternal and fetal state and have implications for understanding fetal learning of the maternal voice under naturalistic conditions.     

Learning to allocate limited time to decisions with different expected outcomes

The goal of this article is to investigate how human participants allocate their limited time to decisions with different properties. We report the results of two behavioral experiments. In each trial of the experiments, the participant must accumulate noisy information to make a decision. The participants received positive and negative rewards for their correct and incorrect decisions, respectively. The stimulus was designed such that decisions based on more accumulated information were more accurate but took longer. Therefore, the total outcome that a participant could achieve during the limited experiments’ time depended on her “decision threshold”, the amount of information she needed to make a decision. In the first experiment, two types of trials were intermixed randomly: hard and easy. Crucially, the hard trials were associated with smaller positive and negative rewards than the easy trials. A cue presented at the beginning of each trial would indicate the type of the upcoming trial. The optimal strategy was to adopt a small decision threshold for hard trials. The results showed that several of the participants did not learn this simple strategy. We then investigated how the participants adjusted their decision threshold based on the feedback they received in each trial. To this end, we developed and compared 10 computational models for adjusting the decision threshold. The models differ in their assumptions on the shape of the decision thresholds and the way the feedback is used to adjust the decision thresholds. The results of Bayesian model comparison showed that a model with time-varying thresholds whose parameters are updated by a reinforcement learning algorithm is the most likely model. In the second experiment, the cues were not presented. We showed that the optimal strategy is to use a single time-decreasing decision threshold for all trials. The results of the computational modeling showed that the participants did not use this optimal strategy. Instead, they attempted to detect the difficulty of the trial first and then set their decision threshold accordingly.     

The association between auditory memory span and speech rate in children from kindergarten to sixth grade.

This study reexamined the association between speech rate and memory span in children from kindergarten to sixth grade (N = 152) in order to potentially account for the inconsistencies within the published literature on this topic. Some of the inconsistencies in past research may reflect the different methods adopted in assessing speech rate. In particular, repeating word triples may itself involve memory demands, contaminating the correlation between speech rate and memory span in younger children. Analyses using composite speech rate and memory span measures showed that speech rate for word triples shared variance with memory span that was independent of speech rate for single words. Moreover, speech rate for word triples was largely redundant with age in explaining additional variation in memory span once the effects of speech rate for single words were controlled.     

Autoshaped head poking in the mouse: a quantitative analysis of the learning curve

In autoshaping experiments, we quantified the acquisition of anticipatory head poking in individual mice, using an algorithm that finds changes in the slope of a cumulative record. In most mice, upward changes in the amount of anticipatory poking per trial were abrupt, and tended to occur at session boundaries, suggesting that the session is as significant a unit of experience as the trial. There were large individual differences in the latency to the onset of vigorous responding. "Asymptotic" performance was unstable; large, bidirectional, and relatively enduring changes were common. Given the characteristics of the individual learning curves, it is unlikely that physiologically meaningful estimates of rate of learning can be extracted from group-average learning curves.     

理性看待心房颤动导管消融成功率

随着心房颤动导管消融术的发展,其成功率不断提高,但医学上的消融成功并不一定等同于永久性治愈,且由于心房颤动的复杂性、消融终点多元性、不规范的术后随访制度和医疗体制不合理等诸多因素影响,导管消融成功率往往被无意或有意夸大,术后可能会因为达不到患者期望值而产生医疗纠纷。     

EFFECTS OF RESPONSE SPACING ON ACQUISITION AND RETENTION OF CONDITIONAL DISCRIMINATIONS

Pigeons were exposed to a repeated acquisition procedure in which no delays were imposed and rate of responding was relatively high. They also were exposed to conditions in which delays were arranged between trials within chains or between completed chains, and rates of responding were lower. Number of trials, rate of reinforcement, difficulty of the discrimination, and motivating operations were held constant. Terminal accuracy was highest under the no‐delay condition, in which rate of responding was highest. Effects of trial spacing on retention were mixed and depended on whether delays were imposed between trials within chains or between completed chains. These findings provide basic‐research support for the rapid presentation of trials in direct instruction and for rate building in precision teaching.