scholarly journals Event-related synchronization/desynchronization in terms of manual motor program switching in men

Biologija ◽  
2018 ◽  
Vol 63 (4) ◽  
Author(s):  
Olha Korzhyk ◽  
Olha Pavlovych ◽  
Lyudmyla Shvarts ◽  
Tetyana Shevchuk ◽  
Olena Dmytrotsa ◽  
...  
Keyword(s):  
Index Finger ◽  
Spectral Power ◽  
International System ◽  
Motor Program ◽  
Middle Finger ◽  
Parietal Lobes ◽  
Low Tone ◽  
The Right ◽  
Change Response ◽  
Manual Movement

The scientific community is paying increasing attention to the characteristics of brain processes providing switch of manual motor programs. Thirty-two right-handed men aged 18–23 years participated in the experiment. The EEG registration was performed according to the international system 10/20, with closed eyes during manual reactions in the Go-Stop-Change paradigm. In the case of a low tone (70%), men had to press the left button of the console (go-response) with the right index finger. A high tone (30%) required rapid pressing of the right button (stop-change-response) with the middle finger. Event-related desynchronization and synchronization of the spectral power of the EEG frequency (6 Hz to 23 Hz) were estimated in the Matlab environment. Significant ERS response is established at the frequency of 6 Hz in symmetrical frontal, central and parietal parts, at 9 Hz – in the left parietal area, at 14–15 Hz – in frontal, central, and parietal areas of the right cortex, and at the frequency of 22 Hz – in the right frontal lobe. However, EEG desynchronization is recorded at the frequency of 7–8 Hz in the frontal and central areas of both hemispheres. The most sensitive to the manual movement stop followed by switching to an alternative event is associated with synchronization of electrical cortical activity, which showed higher values of the spectral power at the frequency of 6 Hz and 14–15 Hz in frontal and central allocations, and was lower at the frequency of 16–17 Hz in both parietal lobes than that during the Go-response.

scholarly journals Cortex electrical activity during switching of motor programs among men and women

2018 ◽  
Vol 9 (2) ◽  
pp. 183-188
Author(s):  
O. V. Korzhyk ◽  
O. S. Pavlovych ◽  
O. R. Dmytrotsa ◽  
A. H. Morenko
Keyword(s):  
Electrical Activity ◽  
Spatial Organization ◽  
Motor Program ◽  
Middle Finger ◽  
Relative Increase ◽  
Men And Women ◽  
Low Tone ◽  
The Right ◽  
Change Task ◽  
The Brain

The inhibition of motor response is considered as an important aspect of executive control, as a way of changing behaviour. Gender, as a biological characteristic, stipulates different peculiarities of brain processes and, as a consequence, different behaviour of men and women. In the context of the Stop-Change task, the aim of our study was to examine whether there were differences in the brain processes between men and women. The method of “event-related desynchronization / synchronization” – ERD / ERS EEG – was used to clarify that issue. 36 men and 38 women, healthy, between the ages of 18 and 22, right-handed, participated in the experiment of compliance with bioethical requirements. The application of Stop-Change task required from the participants under the condition of a low tone (600 Hz sound) to quickly press with the help of the index finger and release the left button of the remote control. If there was a high tone (1600 Hz sound) the participant had to rapidly press and release with the help of middle finger the right button of the console. The prevalence of event-related synchronization phenomena of the α- and β-EEG-activity in cortical areas was distinguished in groups of men and women. It was apparently related to some deactivation of the cortex during the switching of motor program that was launched. At the same time, cortical electrical activity acquired certain specific features of the frequency-spatial organization, which could indicate the existence of certain gender characteristics of the brain processes. The weaker ERG EEG among women (compared with men) at 10 Hz, 16 Hz in symmetrical frontal and left central and parietal areas was found. Instead, the relative increase of ERS EEG among women was set in the range of 10 Hz (right central areas), 13 Hz (frontal central areas) and 19 Hz (central parietal areas). Gender differences in the electrical activity of the cortex in the range above 25 Hz of the EEG were characterized by some instability of the ERS and ERD responses in the frequency and spatial aspects.

Choice Reaction Times for Structural Relationships between Possible Response Sequences

1993 ◽  
Vol 77 (3_suppl) ◽  
pp. 1203-1212 ◽  
Author(s):  
Kazunori Shidoji
Keyword(s):  
Index Finger ◽  
Ring Finger ◽  
Reaction Times ◽  
Middle Finger ◽  
Left Hand ◽  
Right Hand ◽  
Structural Relationships ◽  
Middle Ring ◽  
The Right ◽  
Choice Reaction Times

To investigate human motor programming, choice reaction times were measured on tasks for which subjects made choices between two alternative finger-tapping-movement sequences. The total-number-of-responses and the hierarchical editor models were tested. In Exp. 1 the choice was carried on the situations with the same total numbers of possible responses and different structural relations between alternative sequences. The right-hand reaction times in mirror choice (e.g., subject chose between the middle, index, and ring finger sequences of the left or right hand) were shorter than those in nonmirror choice (e.g., subject chose between the middle, index, and ring finger sequence on one hand and the middle, ring, and index finger sequence on the other hand); the total-number-of-responses model was not supported. In Exp. 2 two conditions had the same operation numbers of the hierarchical editor model. In Condition 1 subjects chose between the index finger of the right hand and the ring, index, and middle finger sequence of the left hand. In Condition 2 subjects chose between the index, ring, and middle finger sequences of the left or right hand. The reaction time in the former condition was shorter than that in the latter condition. Exp. 2 exhibited a counterexample of the hierarchical editor model that had been fairly robust in previous studies.

Braille Reading: Effects of Different Hand and Finger Usage

1980 ◽  
Vol 74 (9) ◽  
pp. 338-343 ◽  
Author(s):  
M.J.C. Mommers
Keyword(s):  
Index Finger ◽  
Middle Finger ◽  
Left Index Finger ◽  
The Right ◽  
Left Middle ◽  
Blind Students

Reviews the literature on hand and finger usage in reading braille. Describes an experiment using 25 blind students to test whether they read faster and/or more accurately with: the left index finger rather than the right one; the left middle finger rather than the right one; the index finger rather than the middle finger; and, with spontaneous hand usage (usually both hands), whether the student read faster and/or more accurately than with the index finger of one hand.

Functional Overlap of Finger Representations in Human SI and SII Cortices

2001 ◽  
Vol 86 (4) ◽  
pp. 1661-1665 ◽  
Author(s):  
Cristina Simões ◽  
Markus Mertens ◽  
Nina Forss ◽  
Veikko Jousmäki ◽  
Bernd Lütkenhöner ◽  
...  
Keyword(s):  
Index Finger ◽  
Ring Finger ◽  
Middle Finger ◽  
Response Latencies ◽  
Left Hand ◽  
Tactile Stimuli ◽  
Somatosensory Cortices ◽  
Somatosensory Evoked Fields ◽  
Left And Right ◽  
The Right

We aimed to find out to what extent functional representations of different fingers of the two hands overlap at the human primary and secondary somatosensory cortices SI and SII. Somatosensory evoked fields (SEFs) were recorded with a 306-channel neuromagnetometer from 8 subjects. Tactile stimuli, produced by diaphragms driven by compressed air, were delivered to the fingertips in three different conditions. First, the right index finger was stimulated once every 2 s. Then two other stimuli were interspersed, in different sessions, to right- or left-hand fingers (thumb, middle finger, or ring finger) between the successive right index finger stimuli. Strengths of the responses to right index finger stimuli were evaluated in each condition. Responses to right index finger stimuli were modeled by three current dipoles, located at the contralateral SI and the SII cortices of both hemispheres. The earliest SI responses, peaking around 65 ms, were suppressed by 18% ( P < 0.05) when the intervening stimuli were presented to the same hand; intervening stimuli to the other hand had no effect. The SII responses were bilaterally suppressed by intervening stimuli presented to either hand: in the left SII, the suppression was 39 and 42% ( P < 0.01) and in the right SII 67 and 72% ( P < 0.001) during left- and right-sided intervening stimuli, respectively. Left- and right-sided intervening stimuli affected similarly the SII responses and had no effect on the response latencies. The results indicate a strong and symmetric overlap of finger representations for both hands in the human SII cortices, and a weaker functional overlap for fingers of the same hand in the SI cortex.

Average-Kr Schedule Benefits Generalized Motor Program Learning

2003 ◽  
Vol 97 (1) ◽  
pp. 185-191 ◽  
Author(s):  
Wan X. Yao
Keyword(s):  
Index Finger ◽  
Motor Program ◽  
Parameter Learning ◽  
Knowledge Of Results ◽  
Feedback Analysis ◽  
Timing Errors ◽  
Positive Effects ◽  
Computer Keyboard ◽  
The Right ◽  
Generalized Motor Program

The main purpose of this study was to examine the effects of average Knowledge of Results (KR) on generalized motor program learning and parameter learning. Two groups of participants ( n = 15 per group) performed 80 acquisition trials of sequential timing tasks. All participants were asked to depress sequentially four keys (2, 4, 8, and 6) on the numeric pad portion of the computer keyboard with the index finger of the right hand. The author presented average feedback on timing errors based on 5-trial blocks and compared this feedback schedule with every-trial feedback. Analysis of the delayed no-feedback retention test indicated a strong advantage for the average KR compared with the every-trial condition in both generalized motor program learning and parameter learning. The current results suggest that the average KR schedule may have positive effects on generalized motor program learning and parameter learning.

Neurospect Findings in Patients Exposed to Neurotoxic Chemicals

1994 ◽  
Vol 10 (4-5) ◽  
pp. 561-571
Author(s):  
Gunnar Heuser ◽  
Ismael Mena ◽  
Francisca Alamos
Keyword(s):  
Elderly Patients ◽  
Qualitative Analysis ◽  
Right Hemisphere ◽  
Young Patients ◽  
Chronic Fatigue ◽  
Psychiatric Symptomatology ◽  
Elderly Individuals ◽  
Parietal Lobes ◽  
The Right ◽  
The Brain

Exposures to neurotoxic chemicals such as pesticides, glues, solvents, etc. are known to induce neurologic and psychiatric symptomatology. We report on 41 patients 16 young patients (6 males, 10 females, age 34 8 yrs.) and 25 elderly patients (9 males, 16 females, age 55 7 yrs). Fifteen of them were exposed to pesticides, and 29 to solvents. They were studied with quantitative and qualitative analysis of regional cerebral bood flow (rCBF), performed with 30 mCi of Xe-133 by inhalation, followed by 30 mCi of Tc-HMPAO given intravenously. Imaging was performed with a brain dedicated system, distribution of rCBF was assessed with automatic ROI definition, and HMPAO was normalized to maximal pixel activity in the brain. Results of Xe rCBF are expressed as mean and S.D. in ml/min/100g, and HMPAO as mean and S.D. uptake per ROI, and compared with age-matched controls 10 young and 20 elderly individuals. Neurotoxics HMPAO Uptake Young Elderly R. Orbital frontal R. Dorsal frontal .70 .66 p < 0.05 R. Temporal .64 p < 0.001 R. Parietal .66 .66 We conclude that patients exposed to chemicals present with diminished CBF, worse in the right hemisphere, with random presentation of areas of hypoperfusion, more prevalent in the dorsal frontal and parietal lobes. These findings are significantly different from observations in patients with chronic fatigue and depression, suggesting primary cortical effect, possibly due to a vasculitis process.

scholarly journals P046 Pointing the finger: an unusual presentation of dactylitis

Rheumatology ◽  
2021 ◽  
Vol 60 (Supplement_1) ◽  
Author(s):  
Natalia Cernovschi - Feasey ◽  
Julekha Wajed
Keyword(s):  
Pleural Effusion ◽  
Soft Tissue ◽  
Middle Finger ◽  
Joint Involvement ◽  
Long Bones ◽  
History Of ◽  
Systemic Symptoms ◽  
The Right ◽  
Hands And Feet ◽  
Radiographic Changes

Abstract Background/Aims  Dactylitis is commonly associated with psoriatic arthritis, and regularly presents at Rheumatology clinics. We discuss a case where progressive systemic symptoms lead to the consideration of alternate diagnoses. Methods  A 46-year-old Nepalese woman presented to the Rheumatology department with a 3 month history of diffuse swelling of the right middle finger proximal interphalangeal joint, with the appearance of dactylitis. There was pain on movement, but no other joint involvement. Simultaneously she noticed blurred and decreased vision, which on review by the ophthalmologists, was diagnosed with bilateral uveitis. There was no history of psoriasis, inflammatory bowel disease, or other past medical history of note. There was no travel history in the past 12 months. A diagnosis of a presumed inflammatory arthritis was made. Results  Blood tests showed elevated c-reactive protein 55 (normal &lt;4 mg/l), erythrocyte sedimentation rate 138 (normal 0-22 mm/hr) and an iron deficiency anaemia. Rheumatoid factor and Anti-CCP antibody were negative. Hand radiographs were reported as normal. MRI of the third digit confirmed an enhancing soft tissue collection at the proximal phalanx of the right middle finger. She was referred for a biopsy of this lesion. Interestingly over the subsequent few months, she developed progressive breathlessness. Chest radiograph showed a left pleural effusion. Further tests showed negative serum ACE, Lyme and Toxoplasma screen. Quantiferon test was negative. Pleural aspirate showed a transudate with negative Acid-fast bacillus (AFB) test and culture. CT chest and abdomen showed a persistent pleural effusion, inflammatory changes in the small bowel and thickening of the peritoneum and omentum. In view of the systemic involvement, a peritoneal tissue biopsy was performed. This confirmed chronic granulomatous inflammation with positive AFB stain for mycobacterium tuberculosis. Our patient was started on quadruple anti- TB antibiotics for 6 months. Her systemic symptoms and dactylitis have improved, although there is on-going treatment for her ocular involvement. Conclusion  Approximately 10% of all cases of extrapulmonary TB have osteoarticular involvement. Dactylitis is a variant of tuberculous osteomyelitis affecting the long bones of the hands and feet. It occurs mainly in young children; however adults may be affected also. The first manifestation is usually painless swelling of the diaphysis of the affected bone followed by trophic changes in the skin. The radiographic changes are known as spina ventosa, because of the ballooned out appearance of the bone, although this was not seen in our case. Fibrous dysplasia, congenital syphilis, sarcoidosis and sickle cell anaemia may induce similar radiographic changes in the metaphysis of long bones of hands and feet, but do not cause soft tissue swelling or periosteal reaction. This case highlights the importance of testing for TB, especially in atypical cases of dactylitis, with other systemic features. Disclosure  N. Cernovschi - Feasey: None. J. Wajed: None.

scholarly journals Rerouting the Narrative: Mapping the Online Identity Politics of the Tamil and Palestinian Diaspora

2018 ◽  
Vol 4 (1) ◽  
pp. 205630511876442 ◽  
Author(s):  
Priya Kumar
Keyword(s):  
Identity Politics ◽  
International System ◽  
Transnational Advocacy ◽  
Online Identity ◽  
Web Based ◽  
Web Presence ◽  
Transnational Advocacy Networks ◽  
Mainstream Media ◽  
Identity Based ◽  
The Right

Drawing on the e-Diasporas Atlas project ( www.e-diasporas.fr ) and original empirical research, this study examines the complex role of the World Wide Web in supporting and enabling new types of diaspora identity politics. It compares the online identity politics of two conflict-generated diasporas: Tamils and Palestinians. Both of these stateless diaspora communities maintain a strong web presence and have mobilized around various secessionist attempts, grievance narratives, issue-agendas, and calls for the right to self-determination that have garnered significant attention from the international community and mainstream media in recent times. Analytical concepts from transnational advocacy networks (TANs) and social movement literature are used to draw attention to the dynamic identity-based processes and framing mechanisms that connect diasporic demands and political claims across online and offline environments. The data combine Tamil and Palestinian e-Diasporas hyperlink network maps with web-based content analysis and key respondent interviews. The study argues that online diasporic exchanges transcend host–homeland territorial boundaries and invite comparatively expressive forms of identity-based political engagements that are simultaneously both deeply local and digitally global. In particular, the analysis demonstrates that human rights–based language offers a unique streamlining bridge between various locales, countries of settlement, and the international system more broadly.

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