Tactile sensitivity thresholds for the radial hemi-pulp of the index: A comparison between the Semmes-Weinstein and Cochet-Bonnet tests in 25 healthy subjects

2018 ◽  
Vol 37 (5) ◽  
pp. 295-299 ◽  
Author(s):  
O. Grobnicu ◽  
F. Vinée ◽  
Y. Igeta ◽  
F. Xavier ◽  
T. Bourcier ◽  
...  
Keyword(s):  
Healthy Subjects ◽  
Tactile Sensitivity

scholarly journals Forehead Tactile Hallucination Is Augmented by the Perceived Risk and Accompanies Increase of Forehead Tactile Sensitivity

Sensors ◽  
2021 ◽  
Vol 21 (24) ◽  
pp. 8246
Author(s):  
Jeonghee Kim ◽  
Derrick Knox ◽  
Hangue Park
Keyword(s):  
Perceived Risk ◽  
Healthy Subjects ◽  
Physical Object ◽  
Mental Illnesses ◽  
Virtual Object ◽  
Experimental Setup ◽  
Tactile Sensitivity ◽  
Experimental Setting ◽  
Common Occurrence ◽  
Complicating Factors

Tactile hallucinations frequently occur after mental illnesses and neurodegenerative diseases like Alzheimer’s and Parkinson’s disease. Despite their common occurrence, there are several complicating factors that make it difficult to elucidate the tactile hallucinations. The forehead tactile hallucination, evoked by the physical object approaching to the forehead, can be easily and consistently evoked in healthy-bodied subjects, and therefore it would help with investigating the mechanism of tactile hallucinations. In this pilot study, we investigated the principles of the forehead tactile hallucination with eight healthy subjects. We designed the experimental setup to test the effect of sharpness and speed of objects approaching towards the forehead on the forehead tactile hallucination, in both a physical and virtual experimental setting. The forehead tactile hallucination was successfully evoked by virtual object as well as physical object, approaching the forehead. The forehead tactile hallucination was increased by the increase of sharpness and speed of the approaching object. The forehead tactile hallucination also increased the tactile sensitivity on the forehead. The forehead tactile hallucination can be solely evoked by visual feedback and augmented by the increased perceived risk. The forehead tactile hallucination also increases tactile sensitivity. These experimental results may enhance the understanding of the foundational mechanisms of tactile hallucinations.

The study of complex stereognostic feelings in clinical practice

2015 ◽  
Vol 9 (2) ◽  
pp. 0-0
Author(s):  
Михайлов ◽  
I. Mikhaylov
Keyword(s):  
Healthy Subjects ◽  
Occupational Diseases ◽  
Three Dimensional ◽  
Tactile Sensitivity ◽  
Resonance Imaging ◽  
Electrophysiological Studies ◽  
Post Traumatic ◽  
Adequacy Assessment ◽  
Instrumental Methods ◽  
Tentative Diagnosis

The work is devoted to the author´s method of investigation of tactile sensitivity, within its stereognostic sense, implemented by means of the original three-dimensional figures. It describes the types and forms of figures, especially, the study of the process of multi-component sensory tactile sensitivity. The author gives are examples of the evaluation and interpretation of the results, comparison with clinical data and instrumental methods of research. Testing is conducted on 470 practically healthy subjects and 232 patients with physical, psycho-neurological, psychiatric pathology by means of electrophysiological studies (electroneuromyography, evoked potentials, rheoencephalography, rheovasography), neuroimaging (magnetic resonance imaging).The proposed method of the study can be used for various types of medical examination (medical, military-medical, medical and social). It allows to carry out a differential - tentative diagnosis of several diseases (damage to the central and peripheral nervous systems, post-traumatic, vertebrogenic, endocrine, vascular, psychosomatic, psychiatric genesis of occupational diseases). The advantages of the technique are the adequacy assessment of the dynamics of the disease during treatment and (or) rehabilitation applicability in ambulatory - polyclinic con-ditions. The method can be used for the purpose of professional selection and vocational guidance, including in professions that demand a great deal of difficult-coordinated fine manipulative actions, an important component of which is tactile sensory afferentation (watch plants, jewelry businesses).

Reflex Responses in Upper Limb Muscles to Cutaneous Stimuli

1993 ◽  
Vol 20 (04) ◽  
pp. 271-278 ◽  
Author(s):  
R. Chen
Keyword(s):  
Stimulus Intensity ◽  
Upper Limb ◽  
Healthy Subjects ◽  
Voluntary Contraction ◽  
Cutaneous Reflexes ◽  
Focal Lesions ◽  
Normal Ranges ◽  
Conduction Velocities ◽  
Limb Muscles ◽  
Biphasic Responses

ABSTRACT:Cutaneous reflexes in the upper limb were elicited by stimulating digital nerves and recorded by averaging rectified EMG from proximal and distal upper limb muscles during voluntary contraction. Distal muscles often showed a triphasic response: an inhibition with onset about 50 ms (Il) followed by a facilitation with onset about 60 ms (E2) followed by another inhibition with onset about 80 ms (12). Proximal muscles generally showed biphasic responses beginning with facilitation or inhibition with onset at about 40 ms. Normal ranges for the amplitude of these components were established from recordings on 22 arms of 11 healthy subjects. An attempt was made to determine the alterent fibers responsible for the various components by varying the stimulus intensity, by causing ischemic block of larger fibers and by estimating the afferent conduction velocities. The central pathways mediating these reflexes were examined by estimating central delays and by studying patients with focal lesions

Lutein Complex Supplementation Increases Ocular Blood Flow Biomarkers in Healthy Subjects

2019 ◽  
Vol 89 (1-2) ◽  
pp. 5-12
Author(s):  
Alon Harris ◽  
Brent Siesky ◽  
Amelia Huang ◽  
Thai Do ◽  
Sunu Mathew ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Diastolic Blood Pressure ◽  
Healthy Subjects ◽  
Ocular Blood Flow ◽  
Capillary Blood ◽  
Post Treatment ◽  
Capillary Blood Flow ◽  
Doppler Imaging ◽  
Retinal Capillary

Abstract. Introduction: To investigate the effects of a lutein complex supplementation on ocular blood flow in healthy subjects. Materials and Methods: Sixteen healthy female patients (mean age 36.8 ± 12.1 years) were enrolled in this randomized, placebo-controlled, double-blinded, two-period crossover study. Subjects received daily an oral dose of the lutein with synergistic phytochemicals complex (lutein (10 mg), ascorbic acid (500 mg), tocopherols (364 mg), carnosic acid (2.5 mg), zeaxanthin (2 mg), copper (2 mg), with synergistic effects in reducing pro-inflammatory mediators and cytokines when administered together in combination) and placebo during administration periods. Measurements were taken before and after three-week supplementation periods, with crossover visits separated by a three-week washout period. Data analysis included blood pressure, heart rate, intraocular pressure, visual acuity, contrast sensitivity detection, ocular perfusion pressure, confocal scanning laser Doppler imaging of retinal capillary blood flow, and Doppler imaging of the retrobulbar blood vessels. Results: Lutein complex supplementation produced a statistically significant increase in mean superior retinal capillary blood flow, measured in arbitrary units (60, p = 0.0466) and a decrease in the percentage of avascular area in the superior (−0.029, p = 0.0491) and inferior (−0.023, p = 0.0477) retina, as well as reduced systolic (−4.06, p = 0.0295) and diastolic (−3.69, p = 0.0441) blood pressure measured in mmHg from baseline. Data comparison between the two supplement groups revealed a significant decrease in systemic diastolic blood pressure (change from pre- to post-treatment with lutein supplement (mean (SE)): −3.69 (1.68); change from pre- to post-treatment with placebo: 0.31 (2.57); p = 0.0357) and a significant increase in the peak systolic velocity (measured in cm/sec) in the central retinal artery (change from pre- to post-treatment with lutein supplement: 0.36 (0.19); change from pre- to post-treatment with placebo: −0.33 (0.21); p = 0.0384) with lutein complex supplement; data analyses from the placebo group were all non-significant. Discussion: In healthy participants, oral administration of a lutein phytochemicals complex for three weeks produced increased ocular blood flow biomarkers within retinal vascular beds and reduced diastolic blood pressure compared to placebo.

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