Entrainment to a real time fractal visual stimulus modulates fractal gait dynamics

Fractal patterns characterize healthy biological systems and are considered to reflect the ability of the system to adapt to varying environmental conditions. Previous research has shown that fractal patterns in gait are altered following natural aging or disease, and this has potential negative consequences for gait adaptability that can lead to increased risk of injury. However, the flexibility of a healthy neurological system to exhibit different fractal patterns in gait has yet to be explored, and this is a necessary step toward understanding human locomotor control. Fifteen participants walked for 15 min on a treadmill, either in the absence of a visual stimulus or while they attempted to couple the timing of their gait with a visual metronome that exhibited a persistent fractal pattern (contained long-range correlations) or a random pattern (contained no long-range correlations). The stride-to-stride intervals of the participants were recorded via analog foot pressure switches and submitted to detrended fluctuation analysis (DFA) to determine if the fractal patterns during the visual metronome conditions differed from the baseline (no metronome) condition. DFA α in the baseline condition was 0.77 ± 0.09. The fractal patterns in the stride-to-stride intervals were significantly altered when walking to the fractal metronome (DFA α = 0.87 ± 0.06) and to the random metronome (DFA α = 0.61 ± 0.10) (both p < .05 when compared to the baseline condition), indicating that a global change in gait dynamics was observed. A variety of strategies were identified at the local level with a cross-correlation analysis, indicating that local behavior did not account for the consistent global changes. Collectively, the results show that a gait dynamics can be shifted in a prescribed manner using a visual stimulus and the shift appears to be a global phenomenon.     

Relation of motor,linguistic and temperament factors in epidemiologic subtypes of persistent and recovered stuttering: Initial findings

PurposeThe purpose of this study was to determine the presence of any patterns reflecting underlying subtypes of persistence and recovery across epidemiologic, motor, language, and temperament domains in the same group of children beginning to stutter and followed for several years.MethodsParticipants were 58 2–4-year-old CWS and 40 age and gender matched NFC from four different sites in the Midwest. At the end of the multi-year study, stuttering children were classified as Persistent or Recovered. The same protocol obtaining data to measure stuttering, motor, language and temperament characteristics was used at each site. They have not been included in previous reports.ResultsThe Persistent group performed consistently differently from the Recovered and Control groups. They performed lower on standardized language tests and in phonological accuracy, had greater kinematic variability, and were judged by their parents to be more negative in temperament.ConclusionsThe present study provides data supporting the hypothesis that subtypes of stuttering can be identified along persistency/recovery lines, but results were not definitive.Educational Objectives: Readers will be able to (a) describe the current state of subtypes of stuttering research; (b) summarize possible contributions of epidemiologic, motoric, linguistic and temperament to such subtyping with regard to persistency and recovery.     

Eternalist Theories of Persistence Through Time: Where the Differences Really Lie

The eternalist endurantist and perdurantist theories of persistence through time come in various versions, namely the two versions of perdurantism: the worm view and the stage view, and the two versions of endurantism: indexicalism and adverbialism. Using as a starting point the instructive case of what is depicted by photographs, I will examine these four views, and compare them, with some interesting results. Notably, we will see that two traditional enemies—the perdurantist worm view and the endurantist theories—are more like allies: they are much less different than what is usually thought, and some alleged points of central disagreement fall prey to closer scrutiny. The aim of this paper is to examine carefully all those points, and to call attention to the places where the real differences between these views lie. I will then turn to the perdurantist stage view, and claim that with respect to some central issues it is the view that is the most different from the other three, but that in some places the reason why it different is also the reason why it is less satisfactory.

Persistence and remission of incipient stuttering among high-risk children

This investigation concerns the persistence of stuttering and recovery from it among high-risk children. At the end of the second year of a 6-year prospective study, 26 of 93 preschool children with a parental history of stuttering were classified as stutterers. Four years later, seven of these children were classified as persistent stutterers, and 16 children were classified as recovered stutterers. The articulatory and linguistic skills of these two groups of children and the communicative and speaking behaviors of their mothers, were measured before and after the onset of stuttering. The analysis of these measures revealed that the articulatory skills of the children and the communicative style and language complexity of the mothers differentiated the incipient stutters whose stuttering subsequently became chronic from those who recovered.     

Emotional and motivational reactions to failure: the role of illusions of control and explicitness of feedback

Previous research has found that illusions of control (IOC) can buffer against the emotional consequences of failure and may increase persistence in the face of failure. Theoretical analyses suggest that IOC are most closely related to a better mood and higher motivation if failure feedback is open to reinterpretation. Two experiments were conducted to test the hypothesis that explicitness (vs. ambiguousness) of failure feedback moderates the consequences of IOC following a failure experience. In accord with predictions, it was found that IOC were subsequently related to a better mood (Study 1) and higher persistence (Study 2) if individuals received ambiguous task-inherent failure feedback. In contrast, explicit failure feedback seemed to neutralize the beneficial effects of IOC. These results are discussed with respect to the adaptiveness of IOC.

Responsibility to continue thinking and worrying: evidence of incremental validity

This two-part study examined the role of the responsibility to continue thinking, beliefs that one needs prolonged thinking about stressful problems, in the prediction of excessive worry. This construct is considered to reflect high levels of motivation to continue inflexible thinking and the use of rigid stop rules. In Study 1, 122 students completed questionnaires. A regression analysis revealed that responsibility accounted for a unique variance beyond negative meta-cognitive beliefs about worry. One hundred and fifty students participated in Study 2, where worry was regressed on emotional instability (Neuroticism), responsibility, and other worry-related cognitive variables (intolerance of uncertainty, positive/negative meta-cognitive beliefs, poor problem-solving orientation, and cognitive avoidance). Again, responsibility was a significant predictor, after controlling for emotional instability (Neuroticism) and other worry-related cognitions. These results indicate the incremental validity of the responsibility to continue thinking.     

Situational disengagement and persistence in the face of adversity

Research suggests that the experience of belonging to a group whose academic abilities are negatively stereotyped fosters disidentification over time, that is, the psychological insulation of the self from academic evaluations and outcomes (Crocker, Major, & Steele, 1998). This research tests whether the process of disidentification can ironically improve motivation when mobilized in response to specific situations. Black and White participants were given negative feedback on an ability-diagnostic or non-diagnostic task. Subsequently, all participants were given the opportunity to persist on the task and their level of disengagement was assessed. As hypothesized, Black participants in the diagnostic condition displayed the most persistence as well as the most disengagement and this persistence response was mediated by their disengagement. The results suggest that, in contrast to chronic disengagement, situational disengagement may help facilitate motivation and persistence.     

Taking a naïve other's perspective to debias the hindsight bias: Did it backfire?

Hindsight bias is a phenomenon that occurs when outcome knowledge interferes with the ability to accurately recall judgments made in a previous, naïve state. Also known as the “knew it all along” bias, we aimed to diminish the bias by having individuals take the perspective of a naïve other, as a way of encouraging acceptance that they had, in fact, not known it all along. Adult participants were given blurry-to-clear images incrementally until they were able to identify the object and were then re-presented with the same sequence of images and asked to make a judgment about when they had identified the item correctly the first time. They were also asked to judge when they thought a naïve peer (Experiments 1 and 2), or a naïve child (Experiment 2) could identify the objects. Results showed a robust hindsight bias in all perspectives, and sporadic success at eliminating the bias. When taking the perspective of a naïve peer, there were failures and successes; when taking the perspective of a naïve child, there was an ultra-debiasing, or a reverse hindsight bias. However, did the manipulation backfire? We conclude that while the manipulation of thinking like a naïve child may have eliminated the bias, participants seemed to use an “adults know best” rule rather than accepting past naivete for themselves.     

Temperament and Character Inventory - Revised (TCI-R) 1 year after the earthquake of L’Aquila (Italy)

The aim of this pilot study was to evaluate the impact of L’Aquila earthquake (Italy) on the Temperament and Character Inventory - Revised (TCI-R) administered 1 year after the earthquake to a community sample of 375 subjects exposed to the earthquake and 480 non-exposed. Exposed people showed variations in the adaptive response to stress with higher Persistence (P) and lower Harm Avoidance (HA) dimensions among adult and lower self directedness (SD) and higher Harm Avoidance (HA) in older people. No differences in young adults were seen. Temperament and character dimensions are sensitive to trauma exposure in different ways in different age groups.     

Blocked goals, persistent action: Implementation intentions engender tenacious goal striving

Research on goal attainment has demonstrated that people are more likely to reach their goals when they form implementation intentions. Three experiments tested whether implementation intentions lead to tenacious goal striving following blockage of an initial attempt to reach the goal. In all three experiments some participants were instructed to form an implementation intention and other participants were not. Subsequently, the initial goal-directed attempt of all participants was unexpectedly blocked. Experiment 1 found that implementation intentions resulted in more attempts to realize one’s goal. Experiment 2 showed that when participants formed an implementation intention their repeated attempt was acted out as intensely as their first, blocked attempt. Experiment 3 found that implementation intentions still allow people to seize an alternative, more onerous means to realize their intention. These results imply that implementation intention conserve self-regulatory strength. After goal blockage, the remaining strength can be used to continue goal-directed action.