Effect of active head movements about the pitch, roll, and yaw axes on human optokinetic afternystagmus

1988 ◽  
Vol 66 (6) ◽  
pp. 689-696 ◽  
Author(s):  
S. H. Lafortune ◽  
D. J. Ireland ◽  
R. M. Jell
Keyword(s):  
Head Movements ◽  
Horizontal Velocity ◽  
Velocity Storage ◽  
Long Term Effects ◽  
Otolith Organ ◽  
Complex Interactions ◽  
Roll Axis ◽  
The Right ◽  
Left Movement

Effects of active head movements about the pitch, roll, or yaw axes on horizontal optokinetic afternystagmas (OKAN) were examined in 16 subjects to test the hypothesis that otolith organ mediated activity induced by a change in head position can couple to the horizontal velocity storage in humans. Active head movements about the pitch axis, forwards or backwards, produced significant OKAN suppression. Pitch forward head movements exerted the strongest effect. Active head movements about the roll axis towards the right also produced OKAN suppression but only if the tilted position was sustained. No suppression was observed following sustained yaw. However, an unsustained yaw left movement after rightward drum rotation significantly enhanced OKAN. Sustained head movement trials did not significantly alter subsequent control trials. In contrast, unsustained movements about the pitch axis, which involve more complex interactions, exerted long-term effects on subsequent control trials. We conclude that otolith organ mediated activity arising from pitch or roll head movements couples to the horizontal velocity storage in humans, thereby suppressing ongoing OKAN. Activity arising from the horizontal canals during an unsustained yaw movement (observed mainly with yaw left), following drum rotation in a direction contralateral to the movement, may also couple to the velocity storage, resulting in increased activity instead of suppression.

scholarly journals QOL-09. WHOLE-BRAIN WHITE MATTER NETWORK CONNECTIVITY IS DISRUPTED BY PEDIATRIC BRAIN TUMOR TREATMENT

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii432-iii432
Author(s):  
Adeoye Oyefiade ◽  
Kiran Beera ◽  
Iska Moxon-Emre ◽  
Jovanka Skocic ◽  
Ute Bartels ◽  
...  
Keyword(s):  
White Matter ◽  
Pediatric Brain Tumor ◽  
Pediatric Brain Tumors ◽  
Magnetic Resonance Images ◽  
Long Term Effects ◽  
Brain White Matter ◽  
The Right ◽  
Pediatric Brain ◽  
Betweeness Centrality

Abstract INTRODUCTION Treatments for pediatric brain tumors (PBT) are neurotoxic and lead to long-term deficits that are driven by the perturbation of underlying white matter (WM). It is unclear if and how treatment may impair WM connectivity across the entire brain. METHODS Magnetic resonance images from 41 PBT survivors (mean age: 13.19 years, 53% M) and 41 typically developing (TD) children (mean age: 13.32 years, 51% M) were analyzed. Image reconstruction, segmentation, and node parcellation were completed in FreeSurfer. DTI maps and probabilistic streamline generation were completed in MRtrix3. Connectivity matrices were based on the number of streamlines connecting two nodes and the mean DTI (FA) index across streamlines. We used graph theoretical analyses to define structural differences between groups, and random forest (RF) analyses to identify hubs that reliably classify PBT and TD children. RESULTS For survivors treated with radiation, betweeness centrality was greater in the left insular (p < 0.000) but smaller in the right pallidum (p < 0.05). For survivors treated without radiation (surgery-only), betweeness centrality was smaller in the right interparietal sulcus (p < 0.05). RF analyses showed that differences in WM connectivity from the right pallidum to other parts of the brain reliably classified PBT survivors from TD children (classification accuracy = 77%). CONCLUSIONS The left insular, right pallidum, and right inter-parietal sulcus are structurally perturbed hubs in PBT survivors. WM connectivity from the right pallidum is vulnerable to the long-term effects of treatment for PBT.

Inhibition of post-partum maternal behaviour in the rat by injecting an oxytocin antagonist into the cerebral ventricles

1987 ◽  
Vol 112 (2) ◽  
pp. 275-282 ◽  
Author(s):  
E. van Leengoed ◽  
E. Kerker ◽  
H. H. Swanson
Keyword(s):  
Wistar Rats ◽  
Post Partum ◽  
Rapid Onset ◽  
Maternal Behaviour ◽  
Cerebral Ventricles ◽  
Long Term Effects ◽  
Nesting Material ◽  
The Right ◽  
Oxytocin Antagonist

ABSTRACT Endogenous oxytocin released into the brain at parturition may stimulate the onset of maternal behaviour. In this study an attempt was made to block spontaneous maternal behaviour following natural delivery in Wistar rats by the injection of an antagonist of oxytocin into the cerebral ventricles. The analogue antagonist, d(CH2)5-8-ornithine-vasotocin, was administered by injection into a chronically implanted cannula in the right lateral ventricle at hourly intervals, beginning immediately after the expulsion of the first pup. The antagonist did not interfere with the normal progress of parturition or birth-related behaviours. After delivery of the last pup, mothers rested for 40 min in the test cage with the pups having been removed. Four pups and standard nesting material were then presented. Latency to pup carrying and duration of pup manipulation, nest building, and time spent on the nest with the pups, as well as duration of autogrooming and general activity were determined. Saline-injected controls started gathering the pups immediately and usually showed all elements of maternal behaviour within 10 min. Antagonist-treated mothers showed a marked delay in the onset of pup grouping and other maternal behaviours. At the end of 1 h, two out of six mothers had not yet picked up a single infant. Pups left overnight with their mothers were gathered into the nest and suckled, and no long-term effects of the antagonist were evident on retesting. The effectiveness of oxytocin antagonist in suppressing the rapid onset of post-partum maternal behaviour supports the hypothesis that centrally released oxytocin is involved in this process. It is noteworthy that these effects were obtained in Wistar rats, a strain in which oxytocin has failed to accelerate responsiveness to pups in virgin females. J. Endocr. (1987) 112, 275–282

scholarly journals Dynamic CT Scan of the Normal Scapholunate Joint in a Clenched Fist and Radial and Ulnar Deviation

Hand ◽  
2017 ◽  
Vol 13 (6) ◽  
pp. 666-670 ◽  
Author(s):  
Paul M. Kelly ◽  
John G. Hopkins ◽  
Andrew J. Furey ◽  
Daniel S. Squire
Keyword(s):  
Ct Scan ◽  
Range Of Motion ◽  
Ct Imaging ◽  
Dynamic Ct ◽  
Long Term Effects ◽  
Ulnar Deviation ◽  
Left Wrist ◽  
The Right ◽  
User Friendly

Background: Injuries to the scapholunate can have severe long-term effects on the wrist. Early detection of these injuries can help identify pathology. The purpose of this study was to evaluate the motions of the scapholunate joint in normal wrists in a clenched fist and through radial and ulnar deviation using novel dynamic computed tomography (CT) imaging. Methods: Fifteen participants below 40 years of age consented to have their wrist scanned. Eight participants were randomized to have the right wrist scanned and 7 the left wrist. Volunteers were positioned at the back of the gantry with the wrist placed on the table, palmar side down. Participants began with the hand in a relaxed fist position and then proceeded through an established range of motion protocol. Dynamic CT imaging was captured throughout the range of motion. Results: The movement in the healthy scapholunate joint through a clenched fist and radial and ulnar deviation is minimal. The averages were 1.19, 1.01, and 0.95 mm, representing the middle, dorsal, and volar measurements, respectively. Conclusions: This novel dynamic CT scan of the wrist is a user-friendly way of measuring of the scapholunate distance, which is minimal in the normal wrist below 40 years of age.

Off to the right start: how pregnancy and early life can determine future animal health and production

2018 ◽  
Vol 58 (3) ◽  
pp. 459 ◽  
Author(s):  
K. L. Gatford ◽  
C. T. Roberts ◽  
K. L. Kind ◽  
P. I. Hynd
Keyword(s):  
Early Life ◽  
Low Birthweight ◽  
Animal Health ◽  
Developmental Programming ◽  
Developmental Trajectory ◽  
Long Term Effects ◽  
Prenatal Growth ◽  
Underlying Mechanisms ◽  
The Right

Animal producers are well aware that a low-birthweight animal is more likely to die in the first few days of life, and, if it survives, it is likely to perform poorly. We are now coming to appreciate that early life events can permanently change an animal’s developmental trajectory, also often referred to as developmental programming. This is an area of current interest in biomedicine, where the concept is known as the ‘developmental origins of health and disease’ (DOHaD). Current gaps in understanding include many of the underlying mechanisms, and whether and how we might intervene and restore the potential for healthy and productive development. This review introduces the biomedical perspective of developmental programming, reviews some of the evidence for long-term effects of early life exposures on welfare and productivity in animal production, with a focus on prenatal growth and maternal stress in pig production, and discusses options for intervening to improve long-term outcomes.

scholarly journals Studying the Shape Variations of the Back, the Neck, and the Mandibular Angle of Horses Depending on Specific Feeding Postures Using Geometric Morphometrics

Animals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 763
Author(s):  
Federica Raspa ◽  
Angela Roggero ◽  
Claudia Palestrini ◽  
Martina Marten Canavesio ◽  
Domenico Bergero ◽  
...  
Keyword(s):  
Geometric Morphometrics ◽  
Management Practices ◽  
Mixed Model ◽  
Principal Component ◽  
Canonical Variate ◽  
Long Term Effects ◽  
Mandibular Angle ◽  
Variate Analysis ◽  
The Right

The effects of specific feeding positions upon the horse’s shape variations of the back and neck postures as well as the variations of the mandibular angle have never been objectively studied. For this reason, geometric morphometrics was applied. Six horses, aged 14 ± 8 years (mean ± standard deviation, SD), were video-recorded while using three different feeding positions: on the ground—control position (CP); neck held 15 ± 3° below withers height with low hay net position (LP); neck held 15 ± 3° above withers height with high hay net position (HP). Data were analyzed using principal component analysis (PCA), multivariate analysis of variance (MANOVA), and partial least squares (PLS). A mixed model procedure was applied to evaluate differences in the magnitude of the mandibular angle. Whilst differences between individual horses were confirmed by canonical variate analysis (CVA), PCA analysis showed that a characteristic feeding position could also be identified on a group level. During the HP hay net position, the back and neck postures as well the mandibular angle were different compared to those exhibited by horses feeding from CP. In LP hay net position, the back posture more closely resembled those exhibited while feeding from CP; however, no similarity between LP and CP was found for neck posture and mandibular angle. Since only a few degrees of variation of the feeding position can influence back and neck postures, this aspect should be further investigated. The right compromise between horse welfare, horse safety, and management practices need to be further explored and long-term effects should be investigated.

scholarly journals Long-Term Effects of Hypoxia-Reoxygenation on Thioredoxins in Rat Central Nervous System

2020 ◽  
Vol 25 (45) ◽  
pp. 4791-4798
Author(s):  
Matilde Otero-Losada ◽  
Canepa L ◽  
Lucas Udovin ◽  
Tamara Kobiec ◽  
Nicolás Toro-Urrego ◽  
...  
Keyword(s):  
Carotid Artery ◽  
Brain Damage ◽  
Common Carotid Artery ◽  
Ischemia Reperfusion ◽  
Long Term Effects ◽  
Brain Areas ◽  
Artery Ligation ◽  
Term Survival ◽  
The Right

Background: Oxidative stress induced by the oxidative pathway dysregulation following ischemia/ reperfusion has been proposed as an important cause of neuronal death and brain damage. The proteins of the thioredoxin (Trx) family are crucial mediators of protein function regulating the intracellular hydrogen peroxide levels and redox-sensitive post-translational protein changes. Aim: To analyze the expression and distribution of fourteen members of the Trx family, potentially essential for the regeneration upon long-term brain damage, in a perinatal hypoxia-ischemia rat model induced by common carotid artery ligation. Methods: The right common carotid artery (CCA) was exposed by an incision on the right side of the neck, isolated from nerve and vein, and permanently ligated. Sham-surgery rats underwent right CCA surgical exposure but no ligation. Euthanasia was administered to all rats at 30, 60, and 90 days of age. Protein expression and distribution of fourteen members of the Trx family and related proteins (Grx1, Grx2, Grx3, Grx5, Prx1, Prx2, Prx3, Prx4, Prx5, Prx6, Trx1, Trx2, TrxR1, TrxR2) was examined in the most hypoxia susceptible rat brain areas, namely, cerebellum, corpus striatum, and the hippocampus. Results: The thioredoxin proteins displayed a complex, cell-type, and tissue-specific expression pattern following ischemia/reperfusion. Even 60 days after ischemia/reperfusion, Western blot analysis showed a persistent expression of Trx1 and Grx2 in several brain areas. Conclusion: The Trx family of proteins might contribute to long-term survival and recovery supporting their therapeutic use to curtail ischemic brain oxidative damage following an ischemia/reperfusion insult. Characterization of ischemia/reperfusion oxidative brain damage and analysis of the involved mechanisms are required to understand the underneath processes triggered by ischemia/reperfusion and to what extent and in what way thioredoxins contribute to recovery from brain hypoxic stress.

scholarly journals Selective Attention Modulates Neural Substrates of Repetition Priming and “Implicit” Visual Memory: Suppressions and Enhancements Revealed by fMRI

2005 ◽  
Vol 17 (8) ◽  
pp. 1245-1260 ◽  
Author(s):  
Patrik Vuilleumier ◽  
Sophie Schwartz ◽  
Stéphanie Duhoux ◽  
Raymond J. Dolan ◽  
Jon Driver
Keyword(s):  
Selective Attention ◽  
Visual Memory ◽  
Striate Cortex ◽  
Relevant Information ◽  
Neural Substrates ◽  
Long Term Effects ◽  
Repetition Effects ◽  
Behavioral Studies ◽  
The Right

Attention can enhance processing for relevant information and suppress this for ignored stimuli. However, some residual processing may still arise without attention. Here we presented overlapping outline objects at study, with subjects attending to those in one color but not the other. Attended objects were subsequently recognized on a surprise memory test, whereas there was complete amnesia for ignored items on such direct explicit testing; yet reliable behavioral priming effects were found on indirect testing. Event-related fMRI examined neural responses to previously attended or ignored objects, now shown alone in the same or mirror-reversed orientation as before, intermixed with new items. Repetition-related decreases in fMRI responses for objects previously attended and repeated in the same orientation were found in the right posterior fusiform, lateral occipital, and left inferior frontal cortex. More anterior fusiform regions also showed some repetition decreases for ignored objects, irrespective of orientation. View-specific repetition decreases were found in the striate cortex, particularly for previously attended items. In addition, previously ignored objects produced some fMRI response increases in the bilateral lingual gyri, relative to new objects. Selective attention at exposure can thus produce several distinct long-term effects on processing of stimuli repeated later, with neural response suppression stronger for previously attended objects, and some response enhancement for previously ignored objects, with these effects arising in different brain areas. Although repetition decreases may relate to positive priming phenomena, the repetition increases for ignored objects shown here for the first time might relate to processes that can produce “negative priming” in some behavioral studies. These results reveal quantitative and qualitative differences between neural substrates of long-term repetition effects for attended versus unattended objects.

scholarly journals Long-Term Effects of Postearthquake Distress on Brain Microstructural Changes

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Atsushi Sekiguchi ◽  
Yuka Kotozaki ◽  
Motoaki Sugiura ◽  
Rui Nouchi ◽  
Hikaru Takeuchi ◽  
...  
Keyword(s):  
Stressful Events ◽  
Long Term Effects ◽  
Short Term ◽  
Psychological Measures ◽  
Short And Long Term ◽  
Left Thalamus ◽  
The Right ◽  
Development Of Anxiety ◽  
The Brain

Stressful events can have both short- and long-term effects on the brain. Our recent investigation identified short-term white matter integrity (WMI) changes in 30 subjects soon after the Japanese earthquake. Our findings suggested that lower WMI in the right anterior cingulum (Cg) was a pre-existing vulnerability factor and increased WMI in the left anterior Cg and uncinate fasciculus (Uf) after the earthquake was an acquired sign of postearthquake distress. However, the long-term effects on WMI remained unclear. Here, we examined the 1-year WMI changes in 25 subjects to clarify long-term effects on the WMI. We found differential FAs in the right anterior Cg, bilateral Uf, left superior longitudinal fasciculus (SLF), and left thalamus, suggesting that synaptic enhancement and shrinkage were long-term effects. Additionally, the correlation between psychological measures related to postearthquake distress and the degree of WMI alternation in the right anterior Cg and the left Uf led us to speculate that temporal WMI changes in some subjects with emotional distress occurred soon after the disaster. We hypothesized that dynamic WMI changes predict a better prognosis, whereas persistently lower WMI is a marker of cognitive dysfunction, implying the development of anxiety disorders.

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