Postural changes during eye–head movements

Tongue Postures and Tongue Centers: A Study of Acoustic-Articulatory Correspondences Across Different Head Angles

Frontiers in Psychology ◽

10.3389/fpsyg.2021.768754 ◽

2022 ◽

Vol 12 ◽

Author(s):

Chenhao Chiu ◽

Yining Weng ◽

Bo-wei Chen

Keyword(s):

Perturbation Theory ◽

Head Movements ◽

Speech Signals ◽

Tube Model ◽

Postural Changes ◽

Close Relationship ◽

Head Positions

Recent research on body and head positions has shown that postural changes may induce varying degrees of changes on acoustic speech signals and articulatory gestures. While the preservation of formant profiles across different postures is suitably accounted for by the two-tube model and perturbation theory, it remains unclear whether it is resulted from the accommodation of tongue postures. Specifically, whether the tongue accommodates the changes in head angle to maintain the target acoustics is yet to be determined. The present study examines vowel acoustics and their correspondence with the articulatory maneuvers of the tongue, including both tongue postures and movements of the tongue center, across different head angles. The results show that vowel acoustics, including pitch and formants, are largely unaffected by upward or downward tilting of the head. These preserved acoustics may be attributed to the lingual gestures that compensate for the effects of gravity. Our results also reveal that the tongue postures in response to head movements appear to be vowel-dependent, and the tongue center may serve as an underlying drive that covariates with the head angle changes. These results imply a close relationship between vowel acoustics and tongue postures as well as a target-oriented strategy for different head angles.

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Norepinephrine Infusion into Nucleus Basalis Elicits Microarousal in Desflurane-anesthetized Rats

Anesthesiology ◽

10.1097/aln.0b013e31822c5ee1 ◽

2011 ◽

Vol 115 (4) ◽

pp. 733-742 ◽

Cited By ~ 26

Author(s):

Siveshigan Pillay ◽

Jeannette A. Vizuete ◽

J. Bruce McCallum ◽

Anthony G. Hudetz

Keyword(s):

Cerebrospinal Fluid ◽

T Test ◽

Head Movements ◽

Nucleus Basalis ◽

Nucleus Basalis Of Meynert ◽

Delta Power ◽

Norepinephrine Infusion ◽

Artificial Cerebrospinal Fluid ◽

Postural Changes ◽

Visual Cortices

Background The nucleus basalis of Meynert of the basal forebrain has been implicated in the regulation of the state of consciousness across normal sleep-wake cycles. Its role in the modulation of general anesthesia was investigated. Methods Rats were chronically implanted with bilateral infusion cannulae in the nucleus basalis of Meynert and epidural electrodes to record the electroencephalogram in frontal and visual cortices. Animals were anesthetized with desflurane at a concentration required for the loss of righting reflex (4.6 ± 0.5%). Norepinephrine (17.8 nmol) or artificial cerebrospinal fluid was infused at 0.2 μl/min (1 μl total). Behavioral response to infusion was measured by scoring the orofacial, limb, and head movements, and postural changes. Results Behavioral responses were higher after norepinephrine (2.1 ± 1) than artificial cerebrospinal fluid (0.63 ± 0.8) infusion (P < 0.01, Student t test). Responses were brief (1-2 min), repetitive, and more frequent after norepinephrine infusion (P < 0.0001, chi-square test). Electroencephalogram delta power decreased after norepinephrine in frontal (70 ± 7%) but not in visual cortex (P < 0.05, Student t test). Simultaneously, electroencephalogram cross-approximate entropy between frontal and visual cortices increased from 3.17 ± 0.56 to 3.85 ± 0.29 after norepinephrine infusion (P < 0.01, Student t test). Behavioral activation was predictable by the decrease in frontal delta power (logistic regression, P < 0.05). Conclusions Norepinephrine infusion into the nucleus basalis of Meynert can modulate anesthetic depth presumably by ascending activation of the cortex. The transient nature of the responses suggests a similarity with microarousals normally observed during natural sleep, and may imply a mechanism for transient awareness under light anesthesia.

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Postural changes and their effects in elite riders when actively influencing the horse versus sitting passively at trot

Comparative Exercise Physiology ◽

10.3920/cep150035 ◽

2016 ◽

Vol 12 (1) ◽

pp. 27-33 ◽

Cited By ~ 14

Author(s):

M.T. Engell ◽

H.M. Clayton ◽

A. Egenvall ◽

M.A. Weishaupt ◽

L. Roepstorff

Keyword(s):

Motion Capture ◽

Load Distribution ◽

Stance Phase ◽

Sagittal Plane ◽

Statistical Tests ◽

Head Movements ◽

Body Segments ◽

Trunk Movements ◽

Postural Changes ◽

Individual Variations

The objectives were to compare sagittal plane posture of the pelvis, trunk and head of elite dressage riders when they ride actively to train the horse versus sitting passively and following the horses’ movements at trot, and to evaluate the effects of these changes in rider posture on load distribution on the horse’s back. Synchronised motion capture and saddle mat data of seven elite dressage riders were used to measure minimal and maximal angles and range of motion (ROM) for the pelvic, trunk and head segments, the angle between pelvis and trunk segments, phase-shift between pitching motions of pelvis and trunk, and pelvic translation relative to the saddle. Non-parametric statistical tests compared variables between the two rider postures. In the passive rider posture the pelvis, trunk and head showed two pitching cycles per stride. Maximal posterior and anterior pelvic rotation occurred, respectively, early and late in the horse’s diagonal stance phase. Compared with pelvic movements, trunk movements were slightly delayed and head movements were out-of-phase. In the active rider posture the pelvis and trunk pitched further posteriorly throughout the stride. Most of the riders showed similar sagittal plane movements of the axial body segments but with some notable individual variations.

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No effect of artificial gravity on lung function with exercise training during head-down bed rest

International Journal of Astrobiology ◽

10.1017/s1473550415000294 ◽

2015 ◽

pp. 1-7

Author(s):

Longxiang Su ◽

Yinghua Guo ◽

Yajuan Wang ◽

Delong Wang ◽

Changting Liu

Keyword(s):

Lung Function ◽

Pulse Rate ◽

Vital Capacity ◽

Pulmonary Ventilation ◽

Bed Rest ◽

Forced Expiratory Volume ◽

Observation Time ◽

Artificial Gravity ◽

Postural Changes ◽

Expiratory Flow

AbstractTo explore the effectiveness of microgravity simulated by head-down bed rest (HDBR) and artificial gravity (AG) with exercise on lung function. Twenty-four volunteers were randomly divided into control and exercise countermeasure (CM) groups for 96 h of 6° HDBR. Comparisons of pulse rate, pulse oxygen saturation (SpO2) and lung function were made between these two groups at 0, 24, 48, 72, 96 h. Compared with the sitting position, inspiratory capacity and respiratory reserve volume were significantly higher than before HDBR (0° position) (P< 0.05). Vital capacity, expiratory reserve volume, forced vital capacity, forced expiratory volume in 1 s, forced inspiratory vital capacity, forced inspiratory volume in 1 s, forced expiratory flow at 25, 50 and 75%, maximal mid-expiratory flow and peak expiratory flow were all significantly lower than those before HDBR (P< 0.05). Neither control nor CM groups showed significant differences in the pulse rate, SpO2, pulmonary volume and pulmonary ventilation function over the HDBR observation time. Postural changes can lead to variation in lung volume and ventilation function, but a HDBR model induced no changes in pulmonary function and therefore should not be used to study AG CMs.

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Role of pinnae and head movements in localizing pure tones 1The authors would like to thank Mr. Remi Humbert for implementing the experiment in Turbo Pascal and for his further assistance.

Swiss Journal of Psychology ◽

10.1024//1421-0185.58.3.170 ◽

1999 ◽

Vol 58 (3) ◽

pp. 170-179 ◽

Cited By ~ 4

Author(s):

Barbara S. Muller ◽

Pierre Bovet

Keyword(s):

Sound Source ◽

Head Movement ◽

Movement Analysis ◽

Head Movements ◽

Sound Sources ◽

Localization Accuracy ◽

Sound Effects ◽

Posterior Quadrant ◽

Localization Performance ◽

Pure Tones

Twelve blindfolded subjects localized two different pure tones, randomly played by eight sound sources in the horizontal plane. Either subjects could get information supplied by their pinnae (external ear) and their head movements or not. We found that pinnae, as well as head movements, had a marked influence on auditory localization performance with this type of sound. Effects of pinnae and head movements seemed to be additive; the absence of one or the other factor provoked the same loss of localization accuracy and even much the same error pattern. Head movement analysis showed that subjects turn their face towards the emitting sound source, except for sources exactly in the front or exactly in the rear, which are identified by turning the head to both sides. The head movement amplitude increased smoothly as the sound source moved from the anterior to the posterior quadrant.

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Supplemental Material for Something in the Way We Move: Motion Dynamics, Not Perceived Sex, Influence Head Movements in Conversation

Journal of Experimental Psychology Human Perception & Performance ◽

10.1037/a0021928.supp ◽

2011 ◽

Keyword(s):

Head Movements ◽

Sex Influence ◽

Motion Dynamics ◽

The Way

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Postural Changes in Essential Hypertension under Treatment and their Effect on the Renogram

Nuklearmedizin ◽

10.1055/s-0038-1624732 ◽

1971 ◽

Vol 10 (01) ◽

pp. 39-46

Author(s):

C. Alexandrou ◽

E. Papadakis ◽

E. Gyftaki ◽

J. Darsinos

Keyword(s):

Renal Function ◽

Essential Hypertension ◽

Early Diagnosis ◽

Postural Hypotension ◽

Antihypertensive Treatment ◽

Normal Subjects ◽

Upright Position ◽

Postural Changes ◽

Significant Impairment

SummaryRadioisotope renograms were obtained in the upright and prone position in 9 normal subjects, in 5 patients with untreated essential hypertension and in 21 hypertensives under treatment, showing moderate postural hypotension.No significant renographic change were seen in the two positions in normal subjects and untreated hypertensives. Treated hypertensives with postural hypotension showed significant impairment of renal function in the upright position in 15 cases and no change in 6. Renal creatinine clearance was lower in the group that showed renographic changes. Renography in the upright position is suggested as a convenient test for early diagnosis and follow-up of the adverse effects of antihypertensive treatment.

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