Age-Related Differences in the Rhythmic Structure of the Golf Swing

Participants were 20 younger golfers (M age = 19.8 years, SD = 1.84 years) and 20 older golfers (M age = 63.0 years, SD = 2.55 years) who attempted 40- and 80-yard eight-iron shots requiring an adjustment of their force and timing. No age-related differences were found in the tempo or speed of the shot; however, there were differences in the rhythmic relationship between the clubhead force and the weight shift. Whereas younger golfers primarily exhibited a 3 versus 2 polyrhythmic pattern between the peak forces of the clubhead and weight shift, older golfers primarily exhibited a simpler 3 versus 3 rhythmic force pattern by adding a forward weight shift at the beginning of the shot. Additionally, older golfers exhibited less independence between the timing of the clubhead force and weight shift, which indicated greater use of a single integrated coordinative unit rather than 2 units. These findings are interpreted as compensations for age-related slowing and increased temporal variability that help to preserve tempo at a speed comparable to younger adults.     

Diurnal cortisol rhythm and cognitive functioning in toddlers: The Generation R Study

Little is known about the relationship between diurnal cortisol secretion patterns and cognitive function early in life. This population-based study examined whether diurnal cortisol rhythms and cognitive functioning in toddlers are related. Within the Generation R Study, parents of 364 infants (median age: 14.2 months) collected saliva samples at five moments during one day. We assessed the diurnal cortisol rhythm by calculating the area under the curve (AUC), the cortisol awakening response (CAR), and the diurnal slope. Verbal cognitive functioning and fine motor development was determined at age 18 months. Nonverbal cognitive functioning was assessed at age 30 months. A more positive CAR was associated with a lower risk of delay in language comprehension (OR per 1-SD CAR: 0.62, 95%CI: 0.40–0.98, p = .04), a lower risk of nonoptimal fine motor development (OR per 1-SD slope: 0.74, 95%CI: 0.57–0.96, p = .03), and a lower risk of delay in nonverbal cognitive development (OR per 1-SD CAR: 0.58, 95%CI: 0.38–0.90, p = .02). Also, children with flatter slopes had a lower risk of delay in nonverbal cognitive development (OR per 1-SD slope: 0.51, 95%CI: 0.34–0.76, p = .001). Higher AUC levels were associated with a higher risk of delay in language production. These results show that variations in diurnal cortisol rhythms are already associated with variations in cognitive functioning at a young age. Infants with a diurnal cortisol pattern indicative of less stress and more cortisol reactivity, that is, lower AUC levels and a more positive CAR, show a lower risk of delay in cognitive functioning as toddlers.     

Brain electrical activity from encoding to retrieval while maintaining and manipulating information in working memory

ABSTRACT

Differences between working memory maintenance (Mt) and manipulation (Mp) have been studied, mostly in the absence of stimuli (delay period); encoding and retrieval phases have been less explored. The present study assessed differences between Mt and Mp, by means of event-related potentials (ERPs) and event-related synchronisation (ERS) and desynchronisation (ERD) for theta, alpha and beta bands at: encoding, delay period and retrieval; using a delayed-match to sample task (DMST). Twenty-six young volunteers solved two DMST conditions (one for Mt and one for Mp). Higher behavioural accuracy for Mt than for Mp was observed. At encoding, higher amplitude for Mt at posterior regions to N1, P2 and P3 components were observed. In the delay period, differences in ERP components and frontal theta ERD were observed. Meanwhile, at retrieval, P3 amplitude and latency, as well as the theta band were modulated by both process (Mt or Mp) and type of trial (target or non-target stimuli). These findings mainly suggest different attentional implications at encoding, differences at the delay period related with task difficulty, and differential retrieval for Mt or Mp dependent on the process which the information comes from, suggesting that Mt and Mp differ at the very beginning of the processing.     

Towards an auditory account of speech rhythm: application of a model of the auditory 'primal sketch' to two multi-language corpora

The world's languages display important differences in their rhythmic organization; most particularly, different languages seem to privilege different phonological units (mora, syllable, or stress foot) as their basic rhythmic unit. There is now considerable evidence that such differences have important consequences for crucial aspects of language acquisition and processing. Several questions remain, however, as to what exactly characterizes the rhythmic differences, how they are manifested at an auditory/acoustic level and how listeners, whether adult native speakers or young infants, process rhythmic information. In this paper it is proposed that the crucial determinant of rhythmic organization is the variability in the auditory prominence of phonetic events. In order to test this auditory prominence hypothesis, an auditory model is run on two multi-language data-sets, the first consisting of matched pairs of English and French sentences, and the second consisting of French, Italian, English and Dutch sentences. The model is based on a theory of the auditory primal sketch, and generates a primitive representation of an acoustic signal (the rhythmogram) which yields a crude segmentation of the speech signal and assigns prominence values to the obtained sequence of events. Its performance is compared with that of several recently proposed phonetic measures of vocalic and consonantal variability.     

An empirical comparison of rhythm in language and music

Musicologists and linguists have often suggested that the prosody of a culture's spoken language can influence the structure of its instrumental music. However, empirical data supporting this idea have been lacking. This has been partly due to the difficulty of developing and applying comparable quantitative measures to melody and rhythm in speech and music. This study uses a recently-developed measure for the study of speech rhythm to compare rhythmic patterns in English and French language and classical music. We find that English and French musical themes are significantly different in this measure of rhythm, which also differentiates the rhythm of spoken English and French. Thus, there is an empirical basis for the claim that spoken prosody leaves an imprint on the music of a culture.     

Is the heart preadapted to hypoxia? Evidence from fractal dynamics of heartbeat interval fluctuations at high altitude (5,050 m)

The dynamics of heartbeat interval time series over large time scales were studied by a modifed random walk analysis introduced recently asDetrended Fluctuation Analysis. In this analysis, the intrinsic fractal long-range power-law correlation properties of beat-to-beat fluctuations generated by the dynamical system (i.e., cardiac rhythm generator), after decomposition from extrinsic uncorrelated sources, can be quantified by the scaling exponent (α) which, in healthy subjects, for time scales of ∼10⁴ beats is ∼1.0. The effects of chronic hypoxia were determined from serial heartbeat interval time series of digitized twenty-four-hour ambulatory ECGs recorded in nine healthy subjects (mean age thirty-four years old) at sea level and during a sojourn at 5,050 m for thirty-four days (Ev-K2-CNR Pyramid Laboratory, Sagarmatha National Park, Nepal). The group averaged α exponent (±SD) was 0.99±0.04 (range 0.93–1.04). Longitudinal assessment of α in individual subjects did not reveal any effect of exposure to chronic high altitude hypoxia. The finding of α∼1 indicating scale-invariant long-range power-law correlations (1/f noise) of heartbeat fluctuations would reflect a genuinely self-similar fractal process that typically generates fluctuations on a wide range of time scales. Lack of a characteristic time scale along with the absence of any effect from exposure to chronic hypoxia on scaling properties suggests that the neuroautonomic cardiac control system is preadapted to hypoxia which helps prevent excessive mode-locking (error tolerance) that would restrict its functional responsiveness (plasticity) to hypoxic or other physiological stimuli. Editorial Note: A philosopher is, by definition, a lover of wisdom. In the following article, Dr. Dimitrov, as a philosopher, examines the principles that underlie being and thinking as performed by the structures of the brain. He reports his thoughts in a “virtual context.” Virtual, a word enjoying great popularity today, is derived from the Latin word for man; it describes manliness and implies apparent, but not actual, power. In his analysis of how information is dealt with by the human being, the author uses theoretical physics and mathematics that may seem arcane to some readers. A major aspect of his thesis declares that the effective performance of information systems relies not on the structures involved, but on the way they interact.     

Rhythmic finger tapping to cosine-wave modulated metronome sequences: Evidence of subliminal entrainment

Rhythmic finger tapping was examined during synchronization to metronome sequences whose base intervals were slightly perturbed by a cosine-wave function with the period of four samples. Data were collected under perturbation levels of 1%, 3%, 5% and 7% in conjunction with base intervals of 400, 500, and 600 ms. Statistical analysis examined the relationship between the inter-response interval (IRI), inter-stimulus interval (ISI) and synchronization error (SE). It was observed that IRI and SE entrain to the periodicity of the ISI patterns even at perturbation levels close to and below the conscious auditory perception threshold. Furthermore, the similarity between the IRI and ISI increased in proportion to the perturbation level. It was also found that the relative perturbation level had more influence on the synchronization behavior than the absolute level. Finally, the observed rhythmic tracking data were modeled mathematically to examine the likelihood of three possible synchronization strategies.PsycINFO classification: 2330     

QEEG markers of superior shooting performance in skilled marksmen: An investigation of cortical activity on psychomotor efficiency hypothesis

For elite performers, psychomotor behavior's success or failure can be traced to differences in brain dynamics. The psychomotor efficiency hypothesis suggests refined cortical activity through 1) selective activation of task-relevant processes and 2) inhibition of non-essential processes. The use of electroencephalography (EEG) has been applied to investigate psychomotor performance's neural processes. The EEG markers that reflect an elevation of psychomotor efficiency include left temporal alpha (T3 alpha), frontal midline theta (Fm theta), sensorimotor rhythm (SMR), and the coherence between frontal and left temporal regions. However, the relationship between elite performers' task-relevant and non-essential neural processes is still not well understood. Therefore, this study aimed to explore how each task-relevant and inhibition of non-essential processes contribute to superior psychomotor behavior. Thirty-five highly skilled marksmen were recruited to perform 30 shots in the shooting task while the EEG was recorded. The marksmen were divided into two groups (superior & inferior) based on a median split of shooting performance. The superior group exhibited higher accuracy and precision, with a reduction in movement jerk. EEG measures revealed that the superior group exhibited higher SMR before the trigger pull than the inferior group. In addition, the superior group demonstrated reduced Fz-T3 coherence in their bull's eye shots than the missed shots. These results suggest that the superior group exhibited less effortful engagement of task-relevant processes and lower interference from non-essential cortical regions than the inferior group. The study's overall findings support the psychomotor efficiency hypothesis. When comparing highly skilled performers, the slight differences in brain dynamics ultimately contribute to the success or failure of psychomotor performance.     

Trait lasting alteration of the brain default mode network in experienced meditators and the experiential selfhood

Based on the finding in novices that four months of meditation training significantly increases frontal default mode network (DMN) module/subnet synchrony while decreasing left and right posterior DMN modules synchrony, the current study tested the prediction whether experienced meditators (those who are practising meditation intensively for several years) had a change in the DMN “trinity” of modules as a baseline trait characteristic and whether this change is in a similar direction as in the novice trainees who practised meditation for only four months. Comparison of functional connectivity within DMN subnets (measured by electroencephalogram operational synchrony in the three separate DMN modules) between five experienced meditators and 10 naïve participants (who were about to start the meditation training) fully support the prediction. Interpretation that links such DMN subnets changes to the three-dimensional components of the experiential selfhood was proposed.