Corticospinal excitability during preparation for an anticipatory action is modulated by the availability of visual information

2011 ◽  
Vol 105 (3) ◽  
pp. 1122-1129 ◽  
Author(s):  
Welber Marinovic ◽  
Campbell S. Reid ◽  
Anna M. Plooy ◽  
Stephan Riek ◽  
James R. Tresilian
Keyword(s):  
Visual Information ◽  
Moving Objects ◽  
Corticospinal Excitability ◽  
Movement Initiation ◽  
Motor Activation ◽  
Neurophysiological Data ◽  
The Right ◽  
Anticipatory Action ◽  
Perceptual Variable ◽  
Visual Conditions

To intercept rapidly moving objects, people must predict the right time to initiate their actions. The timing of movement initiation in interceptions is thought to be determined when a perceptual variable specifying time to contact reaches a criterion value. If a response needs to be aborted, the performer must make a decision before this moment. It has been recently shown that the minimal time to suppress an anticipatory action takes longer during motion extrapolation than during continuous visual information. In experiment 1, we sought to determine whether or not the availability of visual information would 1) affect the latency to inhibit an anticipatory action, and 2) modulate the level of excitability in the motor cortex (M1). The behavioral results showed that the absence of visual information prolonged the latency to stop the movement as previously reported. The neurophysiological data indicated that corticospinal excitability levels were affected by the availability of visual information. In experiment 2, we sought to verify whether corticospinal excitability levels would also differ between the two visual conditions when the task did not involve response suppression. The results of experiment 2 indicated that excitability levels did not differ between visual conditions. Overall, our findings indicated that the buildup of motor activation can also play a role in determining different latencies to inhibit an anticipatory action. They also suggest that the buildup of motor activation in the corticospinal pathways can be strategically modulated to the requirements of the task during continuous visual information.

Manual Asymmetries in Aimed Movements

1989 ◽  
Vol 41 (3) ◽  
pp. 501-516 ◽  
Author(s):  
Eric A. Roy ◽  
Digby Elliott
Keyword(s):  
Visual Information ◽  
Movement Time ◽  
Delay Condition ◽  
Movement Initiation ◽  
Left Hand ◽  
Right Hand ◽  
Manual Asymmetries ◽  
Pointing Accuracy ◽  
The Right ◽  
Made In

Three hypotheses for the right-hand advantage in aiming movements were examined in these experiments: (1) the right-hand system is more efficient at processing visual information during the movement; (2) subjects make more use of visual information prior to movement initiation when using the right hand; (3) the right hand is less variable in generating force in initiating the pointing response as force demands increase. In the first experiment subjects pointed at a target located directly in front of them from two starting positions which defined short (25-cm) and long (35-cm) movements. The movements were made in three movement times, fast (150 to 249 msec), medium (250 to 349 msec) and slow (350 to 449 msec), under three vision conditions—full vision, and no vision (lights out) with immediate or delayed movement initiation. Performance was measured in movement time and accuracy in amplitude of movement. The results did not completely support any of the hypotheses regarding the right-hand advantage, although the left hand was generally more variable than the right. Also, variability increased with increases in movement length and decreases in movement time. The second experiment was designed to examine further the hypotheses regarding the right-hand advantage. In this experiment the same three visual conditions were used; however, subjects made only fast (<250-msec) movements. Also six rather than two starting positions were used. The increased variability of the left hand was observed again here. Further pointing accuracy with the left hand was more adversely affected in the no-vision delay condition. The implications of these results were discussed as they pertain to understanding the processes involved in visual aiming and the observed manual asymmetries.

scholarly journals Efficacy of the use of unaffected hand containment in unimanual intensive therapy to increase visuomotor coordination in children with hemiplegia: a randomized controlled pilot study

2021 ◽  
Vol 12 ◽  
pp. 204062232110012
Author(s):  
Rocío Palomo-Carrión ◽  
Elisabeth Bravo-Esteban ◽  
Sara Ando-La Fuente ◽  
Purificación López-Muñoz ◽  
Inés Martínez-Galán ◽  
...  
Keyword(s):  
Reaction Time ◽  
Upper Limb ◽  
Visual Information ◽  
Intensive Therapy ◽  
Action Planning ◽  
Reaction Time Task ◽  
Group Differences ◽  
Visuomotor Coordination ◽  
Therapy Program ◽  
Anticipatory Action

Background: The capacity of children with hemiplegia to be engaged in anticipatory action planning is affected. There is no balance among spatial, proprioceptive and visual information, thus altering the affected upper limb visuomotor coordination. The objective of the present study was to assess the improvement in visuomotor coordination after the application of a unimanual intensive therapy program, with the use of unaffected hand containment compared with not using unaffected hand containment. Methods: A simple blind randomized clinical trial was realized. A total of 16 subjects with congenital infantile hemiplegia participated in the study with an age mean of 5.54 years old (SD:1.55). Two intensive protocols for 5 weeks of modified constraint-induced movement therapy (mCIMT) or unimanual therapy without containment (UTWC) were executed 5 days per week (2 h/day). Affected upper limb visuomotor coordination (reaction time, task total time, active range, dynamic grasp) was measured before–after intensive therapy using a specific circuit with different slopes (10°/15°). Results: Statistically significant inter-group differences were found after the intervention, with clinically relevant results for the mCIMT group not seen in UTWC, in the following variables: reaction time 10°slope ( p = 0.003, d = 2.44), reaction time 15°slope ( p = 0.002, d = 2.15) as well as for the task total time 10°slope ( p = 0.002, d = 2.25), active reach 10°slope ( p = 0.002, d = 2.7), active reach 15°slope ( p = 0.003, d = 2.29) and dynamic grasp 10°/15°slopes ( p = <0.001, d = 2.69). There were not statistically significant inter-group differences in the total task time with 15°slope ( p = 0.074, d = 1.27). Conclusions: The use of unaffected hand containment in mCIMT would allow improvements in the affected upper limb’s visuomotor coordination. Thus, it would favor clinical practice to make decisions on therapeutic approaches to increase the affected upper limb functionality and action planning in children diagnosed with infantile hemiplegia (4–8 years old).

scholarly journals A Connectome-Wide Functional Signature of Trait Anger

2021 ◽  
pp. 216770262110302
Author(s):  
M. Justin Kim ◽  
Maxwell L. Elliott ◽  
Annchen R. Knodt ◽  
Ahmad R. Hariri
Keyword(s):  
Functional Connectivity ◽  
Visual Information ◽  
Past Research ◽  
Brain Regions ◽  
Small Sample ◽  
Trait Anger ◽  
Frontal Pole ◽  
Brain Correlates ◽  
Small Sample Sizes ◽  
The Right

Past research on the brain correlates of trait anger has been limited by small sample sizes, a focus on relatively few regions of interest, and poor test–retest reliability of functional brain measures. To address these limitations, we conducted a data-driven analysis of variability in connectome-wide functional connectivity in a sample of 1,048 young adult volunteers. Multidimensional matrix regression analysis showed that self-reported trait anger maps onto variability in the whole-brain functional connectivity patterns of three brain regions that serve action-related functions: bilateral supplementary motor areas and the right lateral frontal pole. We then demonstrate that trait anger modulates the functional connectivity of these regions with canonical brain networks supporting somatomotor, affective, self-referential, and visual information processes. Our findings offer novel neuroimaging evidence for interpreting trait anger as a greater propensity to provoked action, which supports ongoing efforts to understand its utility as a potential transdiagnostic marker for disordered states characterized by aggressive behavior.

scholarly journals A Novel Technique to Assess Rotational Deformities in Lower Extremities

2020 ◽  
Author(s):  
Peyman Bakhshayesh ◽  
Ugwunna Ihediwa ◽  
Sukha Sandher ◽  
Alexandros Vris ◽  
Nima Heidari ◽  
...  
Keyword(s):  
Moving Objects ◽  
Sagittal Plane ◽  
Three Dimensional ◽  
Contralateral Side ◽  
Ct Images ◽  
New Technique ◽  
X Rays ◽  
Digital Technique ◽  
The Right ◽  
Im Nailing

Abstract Introduction: Rotational deformities following IM nailing of tibia has a reported incidence of as high as 20%. Common techniques to measure deformities following IM nailing of tibia are either based on clinical assessment, plain X-rays or CT-scan comparing the treated leg with the uninjured contralateral side. All these techniques are based on examiners manual calculation inherently subject to bias. Following our previous rigorous motion analysis and symmetry studies on hemi pelvises, femurs and orthopaedic implants, we aimed to introduce a novel fully digital technique to measure rotational deformities in the lower legs.Material and Methods: Following formal institutional approval from the Imperial College, CT images of 10 pairs of human lower legs were retrieved. Images were anonymized and uploaded to a research server. Three dimensional CT images of the lower legs were bilaterally reconstructed. The mirrored images of the left side were merged with the right side proximally as stationary and distally as moving objects. Discrepancies in translation and rotation were automatically calculated.Results: Our study population had a mean age of 54 ± 20 years. There were six males and four females. We observed a greater variation in translation (mm) of Centre of Mass (COM) in sagittal plane (CI: -2.959--.292) which was also presented as rotational difference alongside the antero-posterior direction or Y axis (CI: .370-1.035). In other word the right lower legs in our study were more likely to be in varus compared to the left side. However, there were no statistically significant differences in coronal or axial planes.Conclusion: Using our proposed fully digital technique we found that lower legs of the human adults were symmetrical in axial and coronal plane. We found sagittal plane differences which need further addressing in future using bigger sample size. Our novel recommended technique is fully digital and commercially available. This new technique can be useful in clinical practice addressing rotational deformities following orthopaedic surgical intervention. This new technique can substitute the previously introduced techniques.

scholarly journals Ambisonics Sound Source Localization With Varying Amount of Visual Information in Virtual Reality

2021 ◽  
Vol 2 ◽  
Author(s):  
Thirsa Huisman ◽  
Axel Ahrens ◽  
Ewen MacDonald
Keyword(s):  
Virtual Reality ◽  
Visual Information ◽  
Right Hemisphere ◽  
Sound Field ◽  
Auditory Stimuli ◽  
Spatial Cues ◽  
Sound Sources ◽  
Acoustic Localization ◽  
Localization Performance ◽  
The Right

To reproduce realistic audio-visual scenarios in the laboratory, Ambisonics is often used to reproduce a sound field over loudspeakers and virtual reality (VR) glasses are used to present visual information. Both technologies have been shown to be suitable for research. However, the combination of both technologies, Ambisonics and VR glasses, might affect the spatial cues for auditory localization and thus, the localization percept. Here, we investigated how VR glasses affect the localization of virtual sound sources on the horizontal plane produced using either 1st-, 3rd-, 5th- or 11th-order Ambisonics with and without visual information. Results showed that with 1st-order Ambisonics the localization error is larger than with the higher orders, while the differences across the higher orders were small. The physical presence of the VR glasses without visual information increased the perceived lateralization of the auditory stimuli by on average about 2°, especially in the right hemisphere. Presenting visual information about the environment and potential sound sources did reduce this HMD-induced shift, however it could not fully compensate for it. While the localization performance itself was affected by the Ambisonics order, there was no interaction between the Ambisonics order and the effect of the HMD. Thus, the presence of VR glasses can alter acoustic localization when using Ambisonics sound reproduction, but visual information can compensate for most of the effects. As such, most use cases for VR will be unaffected by these shifts in the perceived location of the auditory stimuli.

PROTECTION OF CREDITORS IN THE EXECUTION FIDUCIARY GUARANTEE KENDARAAN MOTOR CREDIT

2015 ◽  
Vol 1 (1) ◽  
pp. 62-75
Author(s):  
Nurwati SH., MH.
Keyword(s):  
Moving Objects ◽  
Legal Aspects ◽  
The Other ◽  
Legal Evidence ◽  
Other Hand ◽  
Credit Guarantees ◽  
Legal Security ◽  
Debt Collection ◽  
The Right ◽  
Direct Execution

ABSTRACTFiduciary security is legal security over on moving objects both tangible and intangible, and building or a house on the land belong to someone else, either registered or not, which cannot be burdened with mortgage rights that keep in control of the fiduciary as collateral of debt repayment. If debtor as Fiduciary giver to be insolvent, so the creditor is entitled to have the fiduciary mentioned. For repayment of the debtor and the creditor in this case is called the right separatists.  There are many direct execution in banking practice about the object credit that are not perfect bound of guarantees or not through the insurance agency. Execution is doing by creditors, which debtor accompanied or not, or the object credit guarantees owner. Execution is done by regular sales or through creditor takeover.  Protection of creditors interest doing by giving legal aspects of registration precedes rights while providing executorial title for the fiduciary receivers benefit, on the other hand, the registration arrangements for certain objects that are not listed cause haziness opportunities of law implementation if it isnot done by carefully and clearly. To protect creditors interests, at the time of the debtor defaults, so that creditors as apreferential rights receiver in debt collection and as legal evidence, so warehouse receipts guarantee that the debtor should be given the imposition of bail.Key: Execution, Fiduciary, Creditors, Debtors

Split brains

2018 ◽  
Author(s):  
Elizabeth Schechter
Keyword(s):  
Visual Field ◽  
Information Exchange ◽  
Visual Information ◽  
Right Hemisphere ◽  
The Other ◽  
Brain Surgery ◽  
Interhemispheric Interaction ◽  
Split Brain ◽  
The One ◽  
The Right

The largest fibre tract in the human brain connects the two cerebral hemispheres. A ‘split-brain’ surgery severs this structure, sometimes together with other white matter tracts connecting the right hemisphere and the left. Split-brain surgeries have long been performed on non-human animals for experimental purposes, but a number of these surgeries were also performed on adult human beings in the second half of the twentieth century, as a medical treatment for severe cases of epilepsy. A number of these people afterwards agreed to participate in ongoing research into the psychobehavioural consequences of the procedure. These experiments have helped to show that the corpus callosum is a significant source of interhemispheric interaction and information exchange in the ‘neurotypical’ brain. After split-brain surgery, the two hemispheres operate unusually independently of each other in the realm of perception, cognition, and the control of action. For instance, each hemisphere receives visual information directly from the opposite (‘contralateral’) side of space, the right hemisphere from the left visual field and the left hemisphere from the right visual field. This is true of the normal (‘neurotypical’) brain too, but in the neurotypical case interhemispheric tracts allow either hemisphere to gain access to the information that the other has received. In a split-brain subject however the information more or less stays put in whatever hemisphere initially received it. And it isn’t just visual information that is confined to one hemisphere or the other after the surgery. Rather, after split-brain surgery, each hemisphere is the source of proprietary perceptual information of various kinds, and is also the source of proprietary memories, intentions, and aptitudes. Various notions of psychological unity or integration have always been central to notions of mind, personhood, and the self. Although split-brain surgery does not prevent interhemispheric interaction or exchange, it naturally alters and impedes it. So does the split-brain subject as a whole nonetheless remain a unitary psychological being? Or could there now be two such psychological beings within one human animal – sharing one body, one face, one voice? Prominent neuropsychologists working with the subjects have often appeared to argue or assume that a split-brain subject has a divided or disunified consciousness and even two minds. Although a number of philosophers agree, the majority seem to have resisted these conscious and mental ‘duality claims’, defending alternative interpretations of the split-brain experimental results. The sources of resistance are diverse, including everything from a commitment to the necessary unity of consciousness, to recognition of those psychological processes that remain interhemispherically integrated, to concerns about what the moral and legal consequences would be of recognizing multiple psychological beings in one body. On the other hand underlying most of these arguments against the various ‘duality’ claims is the simple fact that the split-brain subject does not appear to be two persons, but one – and there are powerful conceptual, social, and moral connections between being a unitary person on the one hand and having a unified consciousness and mind on the other.

Difficult Turned Easy: Suggestion Renders a Challenging Visual Task Simple

2020 ◽  
pp. 095679762095485
Author(s):  
Mathieu Landry ◽  
Jason Da Silva Castanheira ◽  
Jérôme Sackur ◽  
Amir Raz
Keyword(s):  
Mental Imagery ◽  
Visual Information ◽  
Perceptual Experience ◽  
Sensory Input ◽  
Moving Objects ◽  
Visual Stimuli ◽  
Perceptual Information ◽  
Hypnotic Suggestion ◽  
Adult Participants ◽  
The Brain

Suggestions can cause some individuals to miss or disregard existing visual stimuli, but can they infuse sensory input with nonexistent information? Although several prominent theories of hypnotic suggestion propose that mental imagery can change our perceptual experience, data to support this stance remain sparse. The present study addressed this lacuna, showing how suggesting the presence of physically absent, yet critical, visual information transforms an otherwise difficult task into an easy one. Here, we show how adult participants who are highly susceptible to hypnotic suggestion successfully hallucinated visual occluders on top of moving objects. Our findings support the idea that, at least in some people, suggestions can add perceptual information to sensory input. This observation adds meaningful weight to theoretical, clinical, and applied aspects of the brain and psychological sciences.

Response Demands and Blindfolding in the Crossed-Hands Deficit: An Exploration of Reference Frame Conflict

2013 ◽  
Vol 26 (5) ◽  
pp. 465-482 ◽  
Author(s):  
Michelle L. Cadieux ◽  
David I. Shore
Keyword(s):  
Reference Frame ◽  
Visual Information ◽  
Reference Frames ◽  
Internal Reference ◽  
Eyes Closed ◽  
External Reference ◽  
Eyes Open ◽  
Temporal Order Judgments ◽  
Visual Conditions

Performance on tactile temporal order judgments (TOJs) is impaired when the hands are crossed over the midline. The cause of this effect appears to be tied to the use of an external reference frame, most likely based on visual information. We measured the effect of degrading the external reference frame on the crossed-hand deficit through restriction of visual information across three experiments. Experiments 1 and 2 examined three visual conditions (eyes open–lights on, eyes open–lights off, and eyes closed–lights off) while manipulating response demands; no effect of visual condition was seen. In Experiment 3, response demands were altered to be maximally connected to the internal reference frame and only two visual conditions were tested: eyes open–lights on, eyes closed–lights off. Blindfolded participants had a reduced crossed-hands deficit. Results are discussed in terms of the time needed to recode stimuli from an internal to an external reference frame and the role of conflict between these two reference frames in causing this effect.

BDNF Val66Met polymorphism is associated with abnormal interhemispheric transfer of a newly acquired motor skill

2014 ◽  
Vol 111 (10) ◽  
pp. 2094-2102 ◽  
Author(s):  
Olivier Morin-Moncet ◽  
Vincent Beaumont ◽  
Louis de Beaumont ◽  
Jean-Francois Lepage ◽  
Hugo Théoret
Keyword(s):  
Motor Cortex ◽  
Motor Learning ◽  
Motor Skill ◽  
Interhemispheric Transfer ◽  
Corticospinal Excitability ◽  
Genetic Group ◽  
Val66met Polymorphism ◽  
Genotype Group ◽  
Left Hand ◽  
The Right

Recent data suggest that the Val66Met polymorphism of the brain-derived neurotrophic factor (BDNF) gene can alter cortical plasticity within the motor cortex of carriers, which exhibits abnormally low rates of cortical reorganization after repetitive motor tasks. To verify whether long-term retention of a motor skill is also modulated by the presence of the polymorphism, 20 participants (10 Val66Val, 10 Val66Met) were tested twice at a 1-wk interval. During each visit, excitability of the motor cortex was measured by transcranial magnetic stimulations (TMS) before and after performance of a procedural motor learning task (serial reaction time task) designed to study sequence-specific learning of the right hand and sequence-specific transfer from the right to the left hand. Behavioral results showed a motor learning effect that persisted for at least a week and task-related increases in corticospinal excitability identical for both sessions and without distinction for genetic group. Sequence-specific transfer of the motor skill from the right hand to the left hand was greater in session 2 than in session 1 only in the Val66Met genetic group. Further analysis revealed that the sequence-specific transfer occurred equally at both sessions in the Val66Val genotype group. In the Val66Met genotype group, sequence-specific transfer did not occur at session 1 but did at session 2. These data suggest a limited impact of Val66Met polymorphism on the learning and retention of a complex motor skill and its associated changes in corticospinal excitability over time, and a possible modulation of the interhemispheric transfer of procedural learning.

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