Changes In Perceptual Responses Research Articles

Travel Across More Time Zones Results in Worse Perceived Fatigue and Sleep in National-Team Footballers

This study investigated the association between (1)time zone difference and (2)travel direction (east vs west) with posttravel changes in perceptual responses of national-team footballers. Travel schedules from 355 national-team trips (50 elite soccer players) were verified using an online flight database. All players provided perceptual ratings of fatigue, sleep quality, soreness, and stress to calculate changes in scores up to 2days after travel. Trips were categorized as <3, 3 to 6, 6 to 9, or 9+ time zone changes, along with travel direction (eastward or westward). The pretravel to posttravel changes in perceptual ratings at days 1 and 2 postarrival were compared between time zone change and travel direction with linear mixed models. For every time zone crossed, poorer ratings of perceptual fatigue (β = 0.068, P < .001), sleep (β = 0.095, P < .001), soreness (β = 0.0049, P < .001), and total wellness (β = 0.214, P < .001) were observed. However, the models explained only small proportions of the variation in postflight perceptual responses (7%-18%). Regardless, travel across 9+ time zones resulted in significantly worse perceived fatigue, sleep, and total wellness for days 1 and 2 postarrival compared with travel with <6 time zones (P < .05). Additionally, fatigue, sleep, and total scores were worse on day 2 following trips of 9+ time zones. Eastward travel resulted in poorer sleep ratings (β = 0.52, P < .001) than westward travel within time zone groupings. Perceptual ratings of fatigue and sleep become progressively worse as travel increases in national-team soccer players, especially after travel across 9+ time zones and eastward travel.

The acute and early phase effects of blood flow restriction training on ratings of perceived exertion, performance fatigability, and muscular strength in women

BACKGROUND: Blood flow restriction (BFR) resistance training (RT) has garnered recent interest, but female-specific data remains scarce. OBJECTIVE: The purpose was to examine the effects of 2-wks of low-load concentric, isokinetic, reciprocal forearm flexion and extension training, with and without BFR on perceptual responses, performance fatigability, and muscular strength. METHODS: Twenty women were assigned to a BFRT or a non-BFRT group. Each group trained at 30% of concentric peak moment. Each session consisted of 75 concentric, isokinetic, reciprocal forearm flexion extension muscle actions. RPEs were recorded following each set. Pretest and posttest maximal voluntary isometric contraction (MVIC) force was measured, and percent decline was defined as performance fatigability. RESULTS: The RPE values (p&lt; 0.05) increased across sets. Strength (collapsed across muscle action) increased (p&lt; 0.05) from 0-wk (23.7 ± 3.2 Nm) to 2-wk (26.8 ± 2.7 Nm). Independent of group and muscle action, performance fatigability (p&lt; 0.05) increased from 0-wk (10.9 ± 5.0%) to 2-wk (14.1 ± 4.4%). CONCLUSIONS: 2-wks of low-load concentric, reciprocal forearm flexion and extension training resulted in similar training-induced changes in perceptual responses, performance fatigability, and muscular strength between BFRT and non-BFRT. These findings may reduce concerns of increased perceptual responses following BFRRT compared to non-BFRRT.

Gaelic Football Match-Play: Performance Attenuation and Timeline of Recovery.

This study investigated acute changes in markers of fatigue and performance attenuation during and following a competitive senior club-level Gaelic football match. Forty-one players were tested immediately pre-match, at half-time, full-time, 24 h post-match and 48 h post-match. Creatine kinase, drop jump height and contact-time, reactive strength index, countermovement jump height and perceptual responses were assessed at the aforementioned time-points. 18 Hz global positioning system devices were used to record players in-game workload measures. Compared to pre-match, perceptual responses (−27.6%) and countermovement jump height (−3.9%) were significantly reduced at full-time (p < 0.05). Drop jump height (−8.8%), perceptual responses (−27.6%), reactive strength index (−15.6%) and countermovement jump height (−8.6%) were significantly lower 24 h post-match (p < 0.05). Pre-match creatine kinase was significantly increased (+16.2% to +159.9%) when compared to all other time-points (p < 0.05). Total distance, total accelerations, total sprints, sprint distance and average heart rate were all correlated to changes in perceptual responses (r = 0.34 to 0.56, p < 0.05). Additionally, maximum speed achieved (r = 0.34) and sprint distance (r = 0.31) were significantly related to countermovement jump changes (p < 0.05), while impacts (r = 0.36) were correlated to creatine kinase increases (p < 0.05). These results demonstrate that Gaelic football match-play elicits substantial neuromuscular, biochemical and perceptual disturbances.

The developmental precedency of spectral and temporal cues in the perception of the /r-w/ phonemic contrast.

The present study examined acoustical and developmental influences on the categorical perception of /r/ and /w/. One group of adults, and three groups of normally developing preschool children, aged 3, 4, and 5 years, respectively, participated in three experimental conditions. These conditions involved performing a video-game identification task employing three different synthetic ‘‘rock-walk’’ continua. In condition I, the acoustic tokens varied according to both spectral and temporal cues; in condition II, the acoustic tokens varied only with respect to spectral cues; in condition III, the acoustic tokens varied only with respect to temporal cues. As hypothesized, changes in perceptual responses were seen as a function of both age and acoustical cue availability. Temporal cues, relative to spectral cues appeared to be the more salient cue for 3 yr olds, whereas for the 4 yr olds, 5 yr olds, and adults the two types of cues appeared to be equally salient. Other developmental trends evidenced included findings that children, relative to adults, demonstrate greater /r/ perceptual categories, more variable perceptual performance, and a tendency to base their phonemic categorizations on primarily only one cue.

On the role of the amplitude of the fricative noise in the perception of place of articulation in voiceless fricative consonants.

The current study explores the role of the amplitude of the fricative noise in the perception of place of articulation in voiceless fricative consonants. The amplitude of the fricative noise in naturally produced fricative-vowel utterances was varied relative to the vowel and potential changes in perceptual responses were investigated. The amplitude of the fricative noise for [s] and [s] was reduced such that the amplitude of the noise relative to the vowel was similar to [f] and [O], and, conversely, the amplitude of the fricative noise of [f] and [O] was increased such that the amplitude of the noise relative to the vowel was similar to [s] and [s]. The fricative noise was presented to listeners in both its vowel context and in isolation. Results indicated that, when the spectral properties of the fricative noise and formant transitions are compatible, the perceptual effects of the amplitude manipulation of the amplitude of the noise had a small effect on the overall identification of place of articulation, and when effects emerged, they varied across the different fricative stimuli. Moreover, although decreasing the amplitude of [s] and [s] resulted in an increase in [f] and [O] responses, increasing the amplitude of [f] and [O] did not result in an increase in [s] and [s] responses. Implications of these findings for phonetic feature theories are considered.

Adaptive changes in perceptual responses and visuomanual coordination during exposure to visual metrical distortion

The abilities of the human visual system to perform metrical judgements (comparison of lengths, estimation of angles ...) involve the existence of some geometrical structure in the visual perceptual space. The question arises whether this geometrical structure is rigidly determined or is subject to adaptive changes. We have tried to answer the question by using a paradigm in which subjects are exposed to a vertically lengthened visual world and then asked to compare simultaneously presented lengths and to evaluate angles between two lines. Their perceptual responses clearly indicate a plastic adaptation to the deformed environment, though the adaptation was never complete after several days of continuous exposure to strong (25%) lengthening. For a maximum time of exposure of 7 days the rate of adaptation was found to be roughly independent of the initial degree of optical distortion. Visuomanual coordination was also investigated in these subjects, but the responses were less conclusive in this case. because of the high inter-subject variability.

Age and sex differences in responses to Embedded Figures and reversible figures

Responses to Embedded Figures and to a series of Reversible Figures, as given by 9-year-old, 11-year-old, and 13-year-old subjects, were assessed with a view of identifying systematic age and sex differences. The present findings show that: (1) the ontogenetic course of sex differences in perceptual responses follows a zigzagging and overlapping pattern rather than a unidirectional path, and data obtained from adult subjects may offer no valid clues with regard to the existence or direction of sex differences at younger age levels; (2) a particular pattern of sex differences uncovered in a specific perceptual response category supplies no valid indices for the existence of similar sex difference patterns in other and even related response categories; and (3) age changes in perceptual responses, like those pertaining to the pattern of sex differences, also appear to be task, response, and in some cases, sex specific.