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1.
Front Syst Neurosci ; 17: 1306387, 2023.
Article in English | MEDLINE | ID: mdl-38090048

ABSTRACT

Introduction: The normal hemispheric balance can be altered by the asymmetric sensorimotor signal elicited by Cervical Dystonia (CD), leading to motor and cognitive deficits. Methods: Directional errors, peak velocities, movement and reaction times of pointing towards out-of-reach targets in the horizontal plane were analysed in 18 CD patients and in 11 aged-matched healthy controls. Results: CD patients displayed a larger scatter of individual trials around the average pointing direction (variable error) than normal subjects, whatever the arm used, and the target pointed. When pointing in the left hemispace, all subjects showed a left deviation (constant error) with respect to the target position, which was significantly larger in CD patients than controls, whatever the direction of the abnormal neck torsion could be. Reaction times were larger and peak velocities lower in CD patients than controls. Discussion: Deficits in the pointing precision of CD patients may arise from a disruption of motor commands related to the sensorimotor imbalance, from a subtle increase in shoulder rigidity or from a reduced agonists activation. Their larger left bias in pointing to left targets could be due to an increased right parietal dominance, independently upon the direction of head roll/jaw rotation which expands the left space representation and/or increases left spatial attention. These deficits may potentially extend to tracking and gazing objects in the left hemispace, leading to reduced skills in spatial-dependent motor and cognitive performance.

2.
Sci Rep ; 13(1): 12617, 2023 08 03.
Article in English | MEDLINE | ID: mdl-37537328

ABSTRACT

The blinking rate far exceeds that required for moistening the cornea and changes depending on whether a person is resting or engaged in cognitive tasks. During ecological cognitive tasks (such as speaking, reading, and watching videos), blinks occur at breakpoints of attention suggesting a role in information segmentation, but the close relationship between cognition dynamics and blink timing still escapes a full understanding. The aim of the present study is to seek (1) if there is a temporal relationship between blink events and the consecutive steps of cognitive processing, and (2) if blink timing and the intensity of blink-related EEG responses are affected by task-relevance of stimuli. Our results show that, in a classical visual oddball task, (i) the occurrence of blinks is influenced by stimuli, irrespective of their relevance, (ii) blinks following relevant stimuli are only apparently delayed due to the need of finalizing a behavioural response, and (iii) stimulus relevance does not affect the intensity of the blink-related EEG response. This evidence reinforce the idea that blinks are not emitted until the last step of the processing sequence has been completed and suggests that blink-related EEG responses are generated by primary consciousness phenomena which are considered by their nature non-modulable (all-or-nothing) phenomena.


Subject(s)
Blinking , Consciousness , Humans , Attention/physiology , Cognition/physiology , Cornea
3.
Front Neurol ; 14: 1323697, 2023.
Article in English | MEDLINE | ID: mdl-38283677

ABSTRACT

Introduction: Diplegic cerebral palsy (CP) is often associated with musculoskeletal disorders that contribute to worsen walking function. The standard care in these cases is single-event multilevel surgery (SEMLS) followed by rehabilitation. Our aim was to investigate whether a rehabilitation program starting even before SEML could add a benefit with respect to standard postoperative programs considered by previous research. Methods: From 2 months before to 13 months after SEMLS (except for the first month after surgery), the participant underwent a motor training focused on ROM exercises with tactile and kinaesthetic feedback. Walking performance, walking capacity, and quality-of-life were assessed before and after SEMLS at different follow-up times. Results: Walking capacity improved 3 months after SEMLS (i.e., earlier than in current literature) and walking performance improved 12 months after SEMLS (instead of simply returning to baseline as previously reported), with a positive impact on quality-of-life. Conclusions: This case suggests that a rehabilitation program starting even before SEMLS could add benefits over walking function and quality-of-life of children with diplegic CP compared to postoperative programs only.

4.
J Neuroeng Rehabil ; 17(1): 144, 2020 10 28.
Article in English | MEDLINE | ID: mdl-33115487

ABSTRACT

BACKGROUND: The past decade has seen the emergence of rehabilitation treatments using virtual reality. One of the advantages in using this technology is the potential to create positive motivation, by means of engaging environments and tasks shaped in the form of serious games. The aim of this study is to determine the efficacy of immersive Virtual Environments and weaRable hAptic devices (VERA) for rehabilitation of upper limb in children with Cerebral Palsy (CP) and Developmental Dyspraxia (DD). METHODS: A two period cross-over design was adopted for determining the differences between the proposed therapy and a conventional treatment. Eight children were randomized into two groups: one group received the VERA treatment in the first period and the manual therapy in the second period, and viceversa for the other group. Children were assessed at the beginning and the end of each period through both the Nine Hole Peg Test (9-HPT, primary outcome) and Kinesiological Measurements obtained during the performing of similar tasks in a real setting scenario (secondary outcomes). RESULTS: All subjects, not depending from which group they come from, significantly improved in both the performance of the 9-HPT and in the parameters of the kinesiological measurements (movement error and smoothness). No statistically significant differences have been found between the two groups. CONCLUSIONS: These findings suggest that immersive VE and wearable haptic devices is a viable alternative to conventional therapy for improving upper extremity function in children with neuromotor impairments. Trial registration ClinicalTrials, NCT03353623. Registered 27 November 2017-Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT03353623.


Subject(s)
Cerebral Palsy/rehabilitation , Gait Apraxia/rehabilitation , Virtual Reality , Wearable Electronic Devices , Cerebral Palsy/physiopathology , Child , Cross-Over Studies , Female , Gait Apraxia/physiopathology , Humans , Male , Pilot Projects , Single-Blind Method , Upper Extremity/physiopathology
5.
Case Rep Neurol Med ; 2019: 9360542, 2019.
Article in English | MEDLINE | ID: mdl-31223509

ABSTRACT

Carbon monoxide (CO) poisoning is a leading cause of intentional and unintentional poisoning worldwide, associated with mortality and severe morbidity. Some survivors of CO poisoning develop, after a lucid interval, a potentially permanent encephalopathy in the form of cognitive impairment and movement disorders, such as Parkinsonism. One of the most frequent neuroimaging findings is a cerebral white matter damage, but so far its precise cause and specific therapy are still debated. We here report the case of a 33-year-old woman with severe carbon monoxide poisoning who, after a period of lucid interval, presented symptoms of declining motor and cognitive functions. She was treated with 40 sessions of Hyperbaric Oxygen Therapy (HBOT). The therapeutic use of oxygen at supraphysiological pressures might either increase systemic oxidative stress or cause an overproduction of oxygen free radicals as drawbacks. Concurrent use of antioxidants and anti-inflammatory drugs may prevent the side effects of oxygen therapy at supraphysiological pressure due to oxidative stress. For this reason, the patient was also treated with high-dose N-Acetylcysteine and glucocorticoids. Here, we describe the longitudinal monitoring of patient's cognitive abilities and leukoencephalopathy associated with her positive clinical outcome.

6.
Psychol Health Med ; 24(1): 27-34, 2019 01.
Article in English | MEDLINE | ID: mdl-30141703

ABSTRACT

Aim of this study is to examine caregiver burden and family functioning in different neurological conditions. Forty-two primary caregivers of patients with Amyotrophic Lateral Sclerosis (ALS), Alzheimer's Disease and other dementia (AD), Parkinson's Disease (PD), Acquired Brain Injuries (ABI) and Multiple Sclerosis (MS) were administered scales for the evaluation of caregiver burden (CBI) and family functioning (FACES IV). Caregiver burden was overall high, with caregivers of patients with ALS and ABI having exceeded the CBI cut-off score for possible burn-out. The average scores of caregivers of patients with AD or other dementia and PD were close to the cut-off score, whereas those of caregivers of patients with MS were significantly lower than the others. Family cohesion, family satisfaction and the quality of family communication were associated with reduced levels of caregiver burden, whereas disengagement was associated with a higher burden. The data from the present study confirm that caregiver burden is a relevant issue in the context of neurological diseases, especially for those causing higher degrees of impairment. Significant correlations with family functioning emerged as well, highlighting the importance of studying and treating caregiver burden within the context of family relations.


Subject(s)
Amyotrophic Lateral Sclerosis/nursing , Brain Injuries/nursing , Caregivers , Cost of Illness , Dementia/nursing , Family , Multiple Sclerosis/nursing , Parkinson Disease/nursing , Adult , Aged , Aged, 80 and over , Alzheimer Disease/nursing , Female , Humans , Male , Middle Aged
7.
IEEE Trans Neural Syst Rehabil Eng ; 26(7): 1469-1478, 2018 07.
Article in English | MEDLINE | ID: mdl-29985156

ABSTRACT

The past decade has seen the emergence of rehabilitation treatments using virtual reality (VR) environments although translation into clinical practice has been limited so far. In this paper, an immersive VR rehabilitation training system endowed with wearable haptics is proposed for children with neuromotor impairments: it aims to enhance involvement and engagement of patients, to provide congruent multi-sensory afferent feedback during motor exercises and to benefit from the flexibility of VR in adapting exercises to the patient's need. An experimental rehabilitation session conducted with children with cerebral palsy (CP) and developmental dyspraxia (DD) has been performed to evaluate the usability of the system and proof of concept trial of the proposed approach. We compared CP/DD performance with both typically developing children and adult control group. Results show the system was compliant with different levels of motor skills and allowed patients to complete the experimental rehabilitation session, with performance varying according to the expected motor abilities of different groups. Moreover, a kinematic assessmentbased on the presented system has been designed. Obtained results reflected different motor abilities of patients and participants, suggesting suitability of the proposed kinematic assessment as a motor function outcome.


Subject(s)
Hereditary Sensory and Motor Neuropathy/rehabilitation , Virtual Reality , Wearable Electronic Devices , Adolescent , Apraxias/rehabilitation , Biomechanical Phenomena , Cerebral Palsy/rehabilitation , Child , Child, Preschool , Feedback, Sensory , Female , Games, Experimental , Healthy Volunteers , Humans , Male , Motor Skills , Psychomotor Performance , Self-Help Devices , User-Computer Interface
8.
IEEE Int Conf Rehabil Robot ; 2017: 1094-1099, 2017 07.
Article in English | MEDLINE | ID: mdl-28813967

ABSTRACT

The past decade has seen the emergence of rehabilitation treatments using virtual reality environments. One of the advantages in using this technology is the potential to create positive motivation, by means of engaging environments and tasks shaped in the form of serious games. In this work, we propose a novel Neuro Rehabilitation System for children with movement disorders, that is based on serious games in immersive virtual reality with haptic feedback. The system design aims to enhance involvement and engagement of patients, to provide congruent multi-sensory afferent feedback during motor exercises, and to benefit from the flexibility of virtual reality in adapting exercises to the patient's needs. We present a feasibility study of the method conducted through an experimental rehabilitation session in a group of 4 children with Cerebral Palsy and Developmental Dyspraxia, 4 Typically Developing children and 4 healthy adults. Subjects and patients were able to accomplish the proposed rehabilitation session and average performance of the motor exercises in patients were lower, although comparable, to healthy subjects. Together with positive comments reported by children after the rehabilitation session, results are encouraging for application of the method in a prolonged rehabilitation treatment.


Subject(s)
Movement Disorders/rehabilitation , Video Games , Wearable Electronic Devices , Adolescent , Child , Equipment Design , Feasibility Studies , Female , Humans , Male , Movement Disorders/physiopathology , Task Performance and Analysis , Touch/physiology
10.
Restor Neurol Neurosci ; 35(1): 11-24, 2017.
Article in English | MEDLINE | ID: mdl-27858722

ABSTRACT

PURPOSE: As well as obtaining confirmation of the magnocellular system involvement in developmental dyslexia (DD); the aim was primarily to search for a possible involvement of the parvocellular system; and, furthermore, to complete the assessment of the visual chromatic axis by also analysing the koniocellular system. METHODS: Visual evoked potentials (VEPs) in response to achromatic stimuli with low luminance contrast and low spatial frequency, and isoluminant red/green and blue/yellow stimuli with high spatial frequency were recorded in 10 dyslexic children and 10 age- and sex-matched, healthy subjects. RESULTS: Dyslexic children showed delayed VEPs to both achromatic stimuli (magnocellular-dorsal stream) and isoluminant red/green and blue/yellow stimuli (parvocellular-ventral and koniocellular streams). To our knowledge, this is the first time that a dysfunction of colour vision has been brought to light in an objective way (i.e., by means of electrophysiological methods) in children with DD. CONCLUSION: These results give rise to speculation concerning the need for a putative approach for promoting both learning how to read and/or improving existing reading skills of children with or at risk of DD. The working hypothesis would be to combine two integrated interventions in a single programme aimed at fostering the function of both the magnocellular and the parvocellular streams.


Subject(s)
Color Perception/physiology , Contrast Sensitivity/physiology , Cues , Dyslexia/rehabilitation , Evoked Potentials, Visual/physiology , Visual Pathways/physiology , Adolescent , Analysis of Variance , Child , Electroencephalography , Female , Humans , Male , Photic Stimulation
11.
PLoS One ; 11(3): e0150265, 2016.
Article in English | MEDLINE | ID: mdl-26963919

ABSTRACT

Modulation of frontal midline theta (fmθ) is observed during error commission, but little is known about the role of theta oscillations in correcting motor behaviours. We investigate EEG activity of healthy partipants executing a reaching task under variable degrees of prism-induced visuo-motor distortion and visual occlusion of the initial arm trajectory. This task introduces directional errors of different magnitudes. The discrepancy between predicted and actual movement directions (i.e. the error), at the time when visual feedback (hand appearance) became available, elicits a signal that triggers on-line movement correction. Analysis were performed on 25 EEG channels. For each participant, the median value of the angular error of all reaching trials was used to partition the EEG epochs into high- and low-error conditions. We computed event-related spectral perturbations (ERSP) time-locked either to visual feedback or to the onset of movement correction. ERSP time-locked to the onset of visual feedback showed that fmθ increased in the high- but not in the low-error condition with an approximate time lag of 200 ms. Moreover, when single epochs were sorted by the degree of motor error, fmθ started to increase when a certain level of error was exceeded and, then, scaled with error magnitude. When ERSP were time-locked to the onset of movement correction, the fmθ increase anticipated this event with an approximate time lead of 50 ms. During successive trials, an error reduction was observed which was associated with indices of adaptations (i.e., aftereffects) suggesting the need to explore if theta oscillations may facilitate learning. To our knowledge this is the first study where the EEG signal recorded during reaching movements was time-locked to the onset of the error visual feedback. This allowed us to conclude that theta oscillations putatively generated by anterior cingulate cortex activation are implicated in error processing in semi-naturalistic motor behaviours.


Subject(s)
Adaptation, Ocular/physiology , Frontal Lobe/physiology , Motion Perception/physiology , Parietal Lobe/physiology , Theta Rhythm/physiology , Adult , Female , Humans , Male
12.
Neural Plast ; 2016: 4323792, 2016.
Article in English | MEDLINE | ID: mdl-28090357

ABSTRACT

Preterm children have an increased risk of neurodevelopmental impairments which include psychomotor and language retardation. The objectives of the present retrospective cohort study were to examine the effects of an individually adapted, home-based, and family-centred early developmental habilitation program on neurodevelopmental and behavioural outcomes of very preterm children compared with a standard follow-up at 2 years' corrected age. Enrolled infants were retrospectively assigned to the intervention group (61 subjects) or to the control group (62 subjects) depending on whether they had or had not carried out a home-based family-centred early developmental habilitation program focused on environmental enrichment, parent-guided environmental interaction, and infant development. Developmental outcome was assessed for both groups at 24 months' corrected age using the Bayley Scales of Infant Development 2nd Edition. Intervention significantly improved both cognitive and behavioural outcomes. In addition, males had significantly lower scores than females either before or after treatment. However, the treatment was effective in both genders to the same extent. In conclusion, a timely updated environment suitable to the infant's developmental needs could provide the best substrate where the parent-infant relationship can be practised with the ultimate goal of achieving further developmental steps.


Subject(s)
Child Development/physiology , Early Medical Intervention/methods , Environment , Family Nursing/methods , Home Care Services , Infant, Extremely Premature/physiology , Cohort Studies , Female , Follow-Up Studies , Humans , Infant , Infant, Extremely Premature/psychology , Infant, Newborn , Male , Parent-Child Relations , Retrospective Studies , Treatment Outcome
13.
Arch Ital Biol ; 153(1): 1-18, 2015 Mar.
Article in English | MEDLINE | ID: mdl-26441362

ABSTRACT

A series of ERP components, each provided with both a precise timing with respect to stimulation and a specific cortical localization, reflects the temporal succession of processing stages of music information. This makes the musical stimulus potentially usable to probe residual brain functions in non-communicating patients with disorders of consciousness. In an attempt to find a simple stimulation protocol that was suitable for use in a clinical setting, the purpose of this study was to verify whether a minimum-length musical stimulus, provided with a definite music-syntactic connotation, was still able to elicit musical ERPs in a group of eight healthy subjects. The stimulus was composed of the minimum number of chords necessary and sufficient to enable the subject to predict a plausible closure of the sequence (priming) and, at the same time, to provide him/her with the closing chord of the sequence (target), either congruous (probable closing) or not (improbable closing) to the tonal context. The subject's task was to discriminate and recognize the irregular targets. The components that were expected to be elicited, in this experimental situation, were ERAN, N5, P600/LPC. Conversely, in addition to these former components, we unexpectedly observed a N400-like component. To determine whether this component was a real N400, we submitted our data to a sLORETA analysis in order to identify its cortical generators. Irregular chords showed higher current densities with respect to regular ones on the right-sided medial and superior temporal gyri, superior and inferior parietal lobules, fusiform and parahippocampal gyri, and on the bilateral posterior cingulate cortex. In particular, the N400-like wave seems to share with the word-primed music-elicited N400 certain generators that are located in cortical areas BA 21/37 and BA 22. This suggests that even chord-primed chord targets can convey extra-musical meanings and that, consequently, they might be useful in assessing residual higher-order information-processing capabilities in non-communicating patients with disorders of consciousness.


Subject(s)
Cerebral Cortex/physiology , Electroencephalography , Evoked Potentials, Auditory/physiology , Music/psychology , Acoustic Stimulation , Adult , Humans , Male , Mental Processes , Scalp/anatomy & histology
14.
Psychol Health Med ; 20(8): 933-9, 2015.
Article in English | MEDLINE | ID: mdl-25668723

ABSTRACT

Severe brain injuries have long-term consequences on functional status and psychosocial functioning. Family life can be greatly influenced as well, and features of high caregiver burden can emerge. Although the data on caregivers' distress are constantly increasing, less information is available about the role of family functioning. Thirty caregivers of hospitalised patients with severe brain injuries received questionnaires for the evaluation of caregiver burden, family functioning and perceived social support. A semi-structured interview was performed for the evaluation of quality of life. Family cohesion and adaptability positively correlated with caregivers' quality of life and perceived social support. Partner caregivers' scores were significantly higher on the time-dependent burden than those of sons and daughters, whereas the latter scored higher on the emotional burden.


Subject(s)
Brain Injuries/nursing , Caregivers/psychology , Cost of Illness , Family/psychology , Quality of Life/psychology , Social Support , Adult , Aged , Female , Humans , Male , Middle Aged
15.
Restor Neurol Neurosci ; 32(6): 767-87, 2014.
Article in English | MEDLINE | ID: mdl-25281612

ABSTRACT

PURPOSE: We describe the case of a subject in a post-traumatic Minimally Conscious State (MCS) who retrieved full interaction with the environment after midazolam infusion. We studied EEG correlates of the "awakening reaction" in the different domains of frequency, time and cortical topography, along with the intrinsic connectivity within both the task-positive and the linguistic network. METHODS: EEG recorded before and after midazolam administration has been submitted to spectral power analysis, sLORETA analysis and intrinsic connectivity analysis within both functional networks. RESULTS: A critical change in the power spectrum profile was observed after midazolam: a) the power between 1 and 12 Hz decreased, reaching its maximum difference with respect to pre-infusion at about 7 Hz and b) the power between 12 and 30 Hz increased, with a maximum difference at about 15 Hz. At the same time, midazolam induced significant connectivity changes, especially for these two frequency bands, within both functional networks. CONCLUSIONS: We advance some hypotheses about certain aspects of the recovery from the MCS both in terms of anatomo-functional correlations and functional brain systems and we make inferences about the role that some kind of 'catatonic' symptoms might play in determining and/or maintaining this peculiar clinical state.


Subject(s)
Brain/drug effects , Brain/physiopathology , Central Nervous System Agents/therapeutic use , Midazolam/therapeutic use , Persistent Vegetative State/drug therapy , Persistent Vegetative State/physiopathology , Adult , Brain/diagnostic imaging , Craniocerebral Trauma/complications , Electroencephalography , Humans , Male , Persistent Vegetative State/diagnostic imaging , Persistent Vegetative State/etiology , Signal Processing, Computer-Assisted , Tomography, X-Ray Computed
16.
PLoS One ; 9(3): e93252, 2014.
Article in English | MEDLINE | ID: mdl-24676098

ABSTRACT

Recently, the cortical source of blink-related delta oscillations (delta BROs) in resting healthy subjects has been localized in the posterior cingulate cortex/precuneus (PCC/PCu), one of the main core-hubs of the default-mode network. This has been interpreted as the electrophysiological signature of the automatic monitoring of the surrounding environment while subjects are immersed in self-reflecting mental activities. Although delta BROs were directly correlated to the degree of consciousness impairment in patients with disorders of consciousness, they failed to differentiate vegetative state/unresponsive wakefulness syndrome (VS/UWS) from minimally conscious state (MCS). In the present study, we have extended the analysis of BROs to frequency bands other than delta in the attempt to find a biological marker that could support the differential diagnosis between VS/UWS and MCS. Four patients with VS/UWS, 5 patients with MCS, and 12 healthy matched controls (CTRL) underwent standard 19-channels EEG recordings during resting conditions. Three-second-lasting EEG epochs centred on each blink instance were submitted to time-frequency analyses in order to extract the normalized Blink-Related Synchronization/Desynchronization (nBRS/BRD) of three bands of interest (low-alpha, high-alpha and low-beta) in the time-window of 50-550 ms after the blink-peak and to estimate the corresponding cortical sources of electrical activity. VS/UWS nBRS/BRD levels of all three bands were lower than those related to both CTRL and MCS, thus enabling the differential diagnosis between MCS and VS/UWS. Furthermore, MCS showed an intermediate signal intensity on PCC/PCu between CTRL and VS/UWS and a higher signal intensity on the left temporo-parieto-occipital junction and inferior occipito-temporal regions when compared to VS/UWS. This peculiar pattern of activation leads us to hypothesize that resting MCS patients have a bottom-up driven activation of the task positive network and thus are tendentially prone to respond to environmental stimuli, even though in an almost unintentional way.


Subject(s)
Alpha Rhythm , Beta Rhythm , Blinking , Persistent Vegetative State/physiopathology , Adult , Aged , Analysis of Variance , Brain Mapping , Case-Control Studies , Diagnosis, Differential , Electroencephalography , Female , Gyrus Cinguli/physiopathology , Humans , Male , Middle Aged , Persistent Vegetative State/diagnosis , Persistent Vegetative State/etiology , Syndrome , Young Adult
17.
Hum Mov Sci ; 32(3): 498-510, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23628359

ABSTRACT

The purpose of this study was to investigate the factors underlying the ability to plan object-oriented grasping movements in the first two years of life. In particular, we were interested in evaluating the relationship between manual motor planning, object use and infant-parent interaction. In order to achieve this aim, grasping behaviors of nineteen healthy infants, aged nine to 25 months, were examined during naturalistic play sessions with a standard set of toys. Our main finding was that, regardless of age, infants perform a better manual planning when they use an object in a functional rather than non-functional way, suggesting that the planning of an action also depends on knowing the functional properties of an object. In addition, we found that the ability to use objects in a functional way was strongly affected by infant-parent interaction. Thus, level of object use and environmental role must be taken into account in order to understand the development of manual motor planning.


Subject(s)
Awareness , Hand Strength , Motor Skills , Play and Playthings , Problem Solving , Psychology, Child , Psychomotor Performance , Child, Preschool , Exploratory Behavior , Female , Humans , Infant , Male , Parent-Child Relations , Social Environment , Tool Use Behavior
18.
Hum Brain Mapp ; 34(9): 2178-89, 2013 Sep.
Article in English | MEDLINE | ID: mdl-22431380

ABSTRACT

Recently, blink-related delta oscillations (delta BROs) have been observed in healthy subjects during spontaneous blinking at rest. Delta BROs have been linked with continuous gathering of information from the surrounding environment, which is classically attributed to the precuneus. Furthermore, fMRI studies have shown that precuneal activity is reduced or missing when consciousness is low or absent. We therefore hypothesized that the source of delta BROs in healthy subjects could be located in the precuneus and that delta BROs could be absent or reduced in patients with disorders of consciousness (DOC). To test these hypotheses, electroencephalographic (EEG) activity at rest was recorded in 12 healthy controls and nine patients with DOC (four vegetative states, and five minimally conscious states). Three-second-lasting EEG epochs centred on each blink instance were analyzed in both time- (BROs) and frequency domains (event-related spectral perturbation or ERSP and intertrial coherence or ITC). Cortical sources of the maximum blink-related delta power, corresponding to the positive peak of the delta BROs, were estimated by standardized Low Resolution Electromagnetic Tomography. In control subjects, as expected, the source of delta BROs was located in the precuneus, whereas in DOC patients, delta BROs were not recognizable and no precuneal localization was possible. Furthermore, we observed a direct relationship between spectral indexes and levels of cognitive functioning in all subjects participating in the study. This reinforces the hypothesis that delta BROs reflect neural processes linked with awareness of the self and of the environment.


Subject(s)
Blinking/physiology , Brain Mapping , Brain/physiology , Consciousness/physiology , Delta Rhythm/physiology , Adult , Aged , Evoked Potentials/physiology , Female , Humans , Male , Middle Aged , Persistent Vegetative State/physiopathology , Signal Processing, Computer-Assisted , Young Adult
19.
J Neuroeng Rehabil ; 9: 36, 2012 Jun 09.
Article in English | MEDLINE | ID: mdl-22681653

ABSTRACT

This study, conducted in a group of nine chronic patients with right-side hemiparesis after stroke, investigated the effects of a robotic-assisted rehabilitation training with an upper limb robotic exoskeleton for the restoration of motor function in spatial reaching movements. The robotic assisted rehabilitation training was administered for a period of 6 weeks including reaching and spatial antigravity movements. To assess the carry-over of the observed improvements in movement during training into improved function, a kinesiologic assessment of the effects of the training was performed by means of motion and dynamic electromyographic analysis of reaching movements performed before and after training. The same kinesiologic measurements were performed in a healthy control group of seven volunteers, to determine a benchmark for the experimental observations in the patients' group. Moreover degree of functional impairment at the enrolment and discharge was measured by clinical evaluation with upper limb Fugl-Meyer Assessment scale (FMA, 0-66 points), Modified Ashworth scale (MA, 0-60 pts) and active ranges of motion. The robot aided training induced, independently by time of stroke, statistical significant improvements of kinesiologic (movement time, smoothness of motion) and clinical (4.6 ± 4.2 increase in FMA, 3.2 ± 2.1 decrease in MA) parameters, as a result of the increased active ranges of motion and improved co-contraction index for shoulder extension/flexion. Kinesiologic parameters correlated significantly with clinical assessment values, and their changes after the training were affected by the direction of motion (inward vs. outward movement) and position of target to be reached (ipsilateral, central and contralateral peripersonal space). These changes can be explained as a result of the motor recovery induced by the robotic training, in terms of regained ability to execute single joint movements and of improved interjoint coordination of elbow and shoulder joints.


Subject(s)
Psychomotor Performance/physiology , Robotics/instrumentation , Robotics/methods , Stroke Rehabilitation , Upper Extremity/physiology , Adult , Aged , Biomechanical Phenomena , Electromyography , Female , Humans , Male , Middle Aged
20.
Int J Psychophysiol ; 80(1): 44-53, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21238505

ABSTRACT

By means of a narrowband wavelet analysis (0.5-6Hz), EEG delta event-related oscillations (EROs), both time- and phase-locked to spontaneous blinking (delta blink-related oscillations or delta BROs), have recently been demonstrated. On the basis of their spatiotemporal characteristics, delta BROs have been proposed as being involved in an automatic mechanism of maintaining awareness in a visuo-spatial context. The aim of the present study was: a) to investigate whether spontaneous blinking was also able to modulate alpha oscillations and, if so, b) whether this modulation was consistent with delta BROs, in order c) to acquire additional information for a better understanding of the cognitive phenomena underlying blinking. Using a broadband (0.5-100 Hz) continuous wavelet transform (CWT), we analysed a total of 189 three-second EEG epochs time-locked to the blinks of seven healthy volunteers. The EEG signals were submitted both to band-pass filtered cross-trial averaging (to obtain frequency-specific BROs) and to alpha event-related synchronization/desynchronization (i.e., blink-related synchronization/desynchronization, BRS/BRD). The alpha oscillations showed: a) an early BRS; b) a BRD in the same temporal window of the delta BROs and, c) a late BRS. We postulate that: a) the early BRS represents the short-term memory maintenance of the last visually perceived trace of the surroundings; b) the alpha BRD is associated with the comparison between the newly perceived image of the environment and its mnestic representation, and, lastly, c) the late BRS is connected with neuronal recovery phenomena.


Subject(s)
Alpha Rhythm/physiology , Awareness/physiology , Blinking/physiology , Delta Rhythm/physiology , Rest/physiology , Space Perception/physiology , Adult , Data Collection , Electroencephalography/methods , Female , Humans , Male , Time Factors , Young Adult
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