Biomedical subjects

P Pradat-Diehl

Publications and source records attributed to P Pradat-Diehl.

At least 19 recordsLinked to original sources

PubMed2005

Rehabilitation of verbal working memory after left hemisphere stroke.

PRIMARY OBJECTIVE: To assess a rehabilitation programme of working memory. RESEARCH DESIGN: Single case multiple-baseline-across-behaviour design in a patient with chronic stroke suffering from a specific impairment of working memory. METHODS: Rehabilitation included training of storage and processing components of verbal working memory. Outcome was assessed with specific working memory tests, non-specific tasks requiring working memory, non-target tasks not requiring working memory and questionnaires addressing daily-life functioning. This assessment was performed twice before the experimental therapy and once after. RESULTS: Cognitive measures were stable before therapy. A statistically significant improvement was found for target measures and for daily-life skills. In contrast, no change was found on non-target tasks. CONCLUSION: Improvement was not apparently related to spontaneous recovery, since performance was stable before therapy. This study suggests that specific cognitive training may improve working memory in patients with brain injury.

Activities of Daily Living↗

PubMed2004

Right spatial neglect after left hemisphere stroke: qualitative and quantitative study.

OBJECTIVES: Comparatively little research has been conducted on right neglect after left brain damage. The authors sought to assess contralateral neglect in subacute left hemisphere stroke patients using a comprehensive test battery validated in a large control group after right hemisphere stroke. METHODS: Seventy-eight left hemisphere stroke patients were assessed. The test battery included a preliminary assessment of anosognosia and visual extinction, a clinical assessment of gaze orientation and personal neglect, and paper-and-pencil tests of spatial neglect in the peripersonal space. Only nonverbal tests were used. RESULTS: Drawing and cancellation tasks revealed neglect in 10 to 13% of patients. The combined battery was more sensitive than any single test alone. A total of 43.5% of patients showed some degree of neglect on at least one measure. Anatomic analyses showed that neglect was more common and severe when the posterior association cortex was damaged. CONCLUSIONS: The frequency of occurrence of right neglect was, as expected, much lower than that reported in a study using the same assessment battery in right brain damage stroke patients. Nevertheless, neglect was found in a substantial proportion of patients at a subacute stage, suggesting that it should be considered in the rehabilitation planning of left brain damage stroke patients.

Awareness↗

PubMed2003

Spatial and motor neglect in children.

OBJECTIVE: To determine if unilateral spatial neglect can be found in very young children with acquired brain lesions. METHODS: A retrospective study was carried out over a 10-year period in a pediatric rehabilitation department specializing in acquired brain lesions. Twelve cases were selected involving children aged 7 months to 14 years. Neglect was assessed by behavior observation for all children and, depending on age, by drawing, copying, reading, writing, and arithmetic tasks. Seven patients underwent the experimental "Teddy Bear" cancellation task, specially adapted to children. RESULTS: All children exhibited spatial and motor neglect in daily activities. In addition, children who were over 2 years of age made lateralized omissions in paper and pencil tasks as well as in the "Teddy Bear" cancellation task. Nine of the 12 children exhibited left spatial and motor neglect, whereas the other three, all of whom were very young (under 4 years), exhibited right spatial neglect. In three cases, cortical lesions were restricted to one lobe, either the parietal, frontal, or temporal. In eight children, lesions extended over more than one lobe, and one child sustained only subcortical lesions. CONCLUSION: Unilateral spatial and motor neglect occurs even in very young children. Right spatial neglect described in very young children may be related to the development of hemispheric specialization.

Adolescent↗

PubMed2003

[Asomatognosia and oral drive: a psychoanalytical perspective].

OBJECTIVE: The psychoanalytic concept of specular image refers to the complex construction that associates the body image with the language coordinates of the individual, thus making him/her a human subject. The acquisition of this specular image implies the loss of corporeal exchanges between mother and child, i.e., the "neutralization" of those body parts or extensions where these exchanges take place. These conceptions of body image and subjectivity lead to the hypothesis that neurological disturbances of body schema may alter the patients' subjectivity and their relation to the lost "object" insofar as they alter body image. MATERIAL: In the present paper, we present two patients aged under 50, with a unique first ever stroke due to ischemia in the right middle cerebral artery territory and asomatognosia. METHODS: On one hand, Bisiach's protocol was used to assess hemiplegia, sensory troubles, visual troubles, hemineglect and anosognosia, and adapted to assess asomatognosia. On the other hand, subjective data were gathered during a semistructured interview and a self-portrait test. RESULTS: This showed that asomatognosia was accompanied by a destructuration of body image and aberrant oral manifestations involving the paralyzed hand. DISCUSSION-CONCLUSION: The psychological positive phenomena accompanying asomatognosia might correspond to the intrusion of the lost object in the patients' psychic reality, due to the alteration of body schema and body image.

Agnosia↗

PubMed2003

[Pontine infarct after fracture of the skull base].

We report a case of pontine infarct that occurred after facial trauma with a fracture of the skull base. Reports of trauma-induced pontine infarcts have generally involved cervical trauma. This is the first report to our knowledge after facial trauma with skull base fracture. We suggest that intracranial vertebro-basilar dissection could be a possible mechanism.

Adult↗

PubMed2002

Sensitivity of clinical and behavioural tests of spatial neglect after right hemisphere stroke.

OBJECTIVES: The lack of agreement regarding assessment methods is responsible for the variability in the reported rate of occurrence of spatial neglect after stroke. The aim of this study was to assess the sensitivity of different tests of neglect after right hemisphere stroke. METHODS: Two hundred and six subacute right hemisphere stroke patients were given a test battery including a preliminary assessment of anosognosia and of visual extinction, a clinical assessment of gaze orientation and of personal neglect, and paper and pencil tests of spatial neglect in the peripersonal space. Patients were compared with a previously reported control group. A subgroup of patients (n=69) received a behavioural assessment of neglect in daily life situations. RESULTS: The most sensitive paper and pencil measure was the starting point in the cancellation task. The whole battery was more sensitive than any single test alone. About 85% of patients presented some degree of neglect on at least one measure. An important finding was that behavioural assessment of neglect in daily life was more sensitive than any other single measure of neglect. Behavioural neglect was considered as moderate to severe in 36% of cases. A factorial analysis revealed that paper and pencil tests were related to two underlying factors. Dissociations were found between extrapersonal neglect, personal neglect, anosognosia, and extinction. Anatomical analyses showed that neglect was more common and severe when the posterior association cortex was damaged. CONCLUSIONS: The automatic rightward orientation bias is the most sensitive clinical measure of neglect. Behavioural assessment is more sensitive than any single paper and pencil test. The results also support the assumption that neglect is a heterogeneous disorder.

Activities of Daily Living↗

PubMed2001

Preserved adjustment but impaired awareness in a sensory-motor conflict following prefrontal lesions.

Control of action occurs at different stages of the executive process, in particular at those of sensory-motor integration and conscious monitoring. The aim of this study was to determine the implication of the prefrontal cortex in the control of action. For that purpose, we compared the performance of 15 patients with frontal lobe lesions and 15 matched controls on an experimental paradigm generating a conflict between the action planned and the sensory-motor feedback. Subjects had to trace a sagittal line with a stylus on a graphic tablet. The hand was hidden by a mirror on which the traced line, processed by a computer, was projected. Without informing the subjects, the line traced was modified by introducing a bias to the right, which increased progressively from 2 degrees to 42 degrees. To succeed the task, subjects had to modify their motor program and deviate their hand in the opposite direction. The sensory-motor adjustment to the bias was evaluated by the surface between the line traced and the ideal line to compensate for the deviation. The awareness of the conflict was measured by the angle of the bias at which subjects expressed the feeling that the line they traced was not the same as the line they saw. The deviation was similarly compensated for by patients and controls until 24 degrees. Then 14 controls but only 3 patients were aware of a conflict. After that, the variability of performance increased significantly for the unaware patients. These results suggest that the prefrontal cortex is required at the level of conscious monitoring of actions, but not at the level of sensory-motor integration.

Adult↗

PubMed2001

Interruption of a relay of corticospinal excitation by a spinal lesion at C6-C7.

In a patient with a limited lesion of the spinal cord at the C6-C7 junction, ulnar and superficial radial-induced modulations of the motor evoked potentials (MEP) and of ongoing electromyographic (EMG) activity were observed in the biceps (above the lesion) but not in the triceps (below the lesion). This suggests an interruption of the axons of cervical propriospinal neurons. This relay transmits an indirect (disynaptic) component of corticospinal excitation to human upper limb motoneurons. Changes in it might be involved in compensatory mechanisms following central motor disorders.

Cervical Vertebrae↗

PubMed2001

Neurological complications of primary Sjögren's syndrome.

OBJECTIVE: To better delineate the spectrum of neurological complications of primary Sjögren's syndrome (PSS). METHODS: A detailed neurological investigation was prospectively performed in a group of 25 consecutive patients with PSS followed in an internal medicine department between June 1996 and December 1997 (Internal Medicine group). In addition, eleven patients with neurological complications of PSS were identified in the Neurological Department of the same institution during the same period (Neurological group). RESULTS: In the Internal Medicine group, neurological complications were discovered in 10/25 (40%) patients. Peripheral nervous system involvement was present in 4/25 patients from the Internal Medicine group and in 10/11 patients from the Neurological group and consisted mainly of axonal sensorimotor/sensory polyneuropathy. A motor neuron syndrome was identified in two patients. CNS involvement occurred in 7/25 patients from the Internal Medicine group and in 4/11 patients from the Neurological group. Three patients had spinal cord involvement. Cognitive dysfunction was the most frequent finding (5/25 in the Internal Medicine group, 3/11 in the Neurological group) characterized either by subcortical or corticosubcortical dysfunction. Cognitive impairment was not attributed to mood disturbance and was not associated with specific laboratory or radiological abnormalities. CONCLUSION: Neurological complications of PSS are frequent since they were present in 40% (10/25) of patients in a consecutive series of patients from a department of Internal Medicine. Although PNS involvement predominates, complications of PSS affecting the brain or spinal cord are not rare, with subcortical dysfunction as the main finding.

Adult↗

PubMed2001

[What is a "left"?].

OBJECTIVE: Patients with right hemisphere syndrome may be labeled as "gauche" by the rehabilitation staff. This term corresponds to a variety of oddities in behavior or discourse. The aim of this study is to understand the coherence of these oddities with the classical elements of right hemisphere syndrome. MATERIAL: In this article, we present a detailed study of the discourse and the relation with others of a patient with severe left hemineglect, who was followed up for twelve months and did not exhibited any significant change in his symptomatology. METHODS: This study relies on the data from neuropsychological examination, on notes written after rehabilitation session by the therapists and on data from weekly non-directive interviews. RESULTS: This follow-up revealed disturbances of time sense, reduplication for places, misidentification of therapists, pseudo hallucinations, and showed that the transferential relation was "floating". The non-directive interviews permitted the patient to express his own interpretation of his troubles. He described them in terms of gaps in his body "carapace" and disorganization of the oral drive. CONCLUSION: We propose to consider the symptomatology of this patient in relation with the subjective effects of the breaking up of his body image and the concomitant intrusion of the oral object (in the psychoanalytic sense of this term) in his psychic reality.

Agnosia↗

PubMed2001

[Long term outcome of a severe non fluent aphasia. The effect of prolonged rehabilitation].

INTRODUCTION: Long-term clinical outcome of severe non-fluent aphasia is poorly reported. The efficacy of intensive speech therapy has been previously demonstrated but not the efficacy of prolonged speech rehabilitation. METHOD: We report a single case of aphasia, with a description of the initial clinical features and the long term outcome. Moreover we discuss the rehabilitation efficacy in two situations : delayed rehabilitation and long-lasting rehabilitation. RESULTS: A young adult was admitted after fronto-temporal cerebral infarction and presented with a severe non fluent aphasia. Spontaneous recovery involved comprehension but not verbal expression. Speech therapy began 10 months after onset and an improvement of oral expression was observed during at least 6 years. DISCUSSION: This case illustrates long term-recovery patterns of aphasia and the efficacy of delayed speech therapy, and moreover its efficacy at a long time after onset. No rehabilitation was performed during the period of spontaneous recovery. Consequently recovery of spontaneous oral expression can be attributed to speech rehabilitation. Furthermore long-lasting improvement can also be attributed to prolonged rehabilitation. Total amount of speech therapy for the patient can be similar to the amount of efficacious intensive therapy previously described. CONCLUSION: These findings confirm the efficacy of speech therapy in the late stage of recovery, and the possibility of late improvement after stroke.

Adult↗

PubMed2001

[Unilateral spatial and motor neglect in children].

Although unilateral spatial neglect is well documented in adults after a cerebral damage, the description in children is rare and no motor neglect has yet been reported. We report four children age range from three to thirteen years old, in patients in a rehabilitation department. A cancellation task "the Teddy bear test" was used to assess spatial neglect in children. The children were presented a page containing line drawings of usual objects, including fifteen Teddy bears. The children were asked to cross out each Teddy bear. These four children omitted five to eleven teddy bears located on the left space, whereas children of the controlled group never omitted more than one Teddy bear. The four children also exhibited neglect in drawings, and during daily life activities. Moreover, one of them had a motor neglect with no more defects of strength and an under-utilization of his left side. Spatial unilateral neglect and motor neglect should be systematically investigated in children after a cerebral damage, and should be considered during rehabilitation.

Adolescent↗

PubMed2001

[Conduction aphasia and phonemic disorder].

Conduction aphasia is usually described as a repetition impairment. Semiology or pathophysiology cannot be explained with this definition. We report a single case particularly demonstrative. The patient showed spontaneous speech, denomination, repetition and reading impairments. Main errors were phonemic paraphasia. No arthric disorder nor comprehension impairment was observed. Damage of supramarginalis gyrus and Wernicke's area was found. A cognitive analysis suggested that the phonological buffer and the working memory were impaired. Implication for rehabilitation, which included segmentation and semantisation associated to phonological training, is discussed. The course of the conduction aphasia was good and the patient was able to work again.

Aphasia, Conduction↗

PubMed2001

[Presenting a battery for assessing spatial neglect. Norms and effects of age, educational level, sex, hand and laterality].

The aim of this study was to build up a battery for assessing spatial neglect, then to analyse the norms and potential effects of age, education level, sex, hand used, and laterality. It was also to contribute evaluating the pseudoneglect phenomenon described by Heilman, which consists in a tendency of normal subjects to neglect the right peripersonal space. Tasks selected were presented to important groups of normal subjects, most often larger than 450. The battery comprised of a bell cancellation test, scene copy, clock drawing, two line bisection tasks, identification of overlapping figures, text reading, writing task, and the representational task of the France map. For each of them, different variables were selected, especially investigating the difference between performance in the right and the left hemispaces. This study allowed defining the threshold values (percentiles 5 and 95) for deciding of the pathological character of a patient performance. It also showed that the pseudoneglect phenomenon is more obvious in some tasks such as line bisection, and probably also in the representational task of the France map and writing. His importance and at times his side were influenced by the factors we studied, with between tasks differences, but also by the nature of the task to be performed, and especially his verbal component.

Adult↗

PubMed2000

An ecological approach to planning dysfunction: script execution.

Planning, which concerns many activities in everyday life, is a two-stage process. The first one predetermines a course of actions aimed at achieving some specific goals. It is founded on managerial knowledge or overlearned sequences of events and may be tested by script generation. The second stage entails monitoring and guiding the execution of the plan to a successful conclusion. It must take into account environmental contingencies and may be tested by script execution. If the frontal lobes intervene not only in managerial knowledge (Grafman, 1989) but also in binding the plan with contextual environment (Damasio, Tranel and Damasio, 1991; Shallice and Burgess, 1991), script execution would be more sensitive than script generation to planning deficits. To test this hypothesis, script execution and script generation were compared in 11 patients with a dysexecutive syndrome and 10 matched controls, using three scripts of daily life activities: (1) 'shopping for groceries'; (2) 'cooking'; (3) 'answering a letter and finding the way to post the reply'. Two way ANOVAs showed more errors in execution than in generation, more errors in patients than in controls, and a greater difference between execution and generation in patients than in controls. Furthermore, 'context neglect' and 'environmental adherence' were the two types of errors that best differentiated patients from controls. Finally, the total number of errors in execution correlated with the score on behavioral questionnaires answered by occupational therapists. These results confirm our hypothesis and suggest that script execution may be a valid ecological approach to estimate the severity of deficits in daily life activities.

Activities of Daily Living↗

PubMed2000

Presynaptic inhibition and homosynaptic depression: a comparison between lower and upper limbs in normal human subjects and patients with hemiplegia.

Presynaptic inhibition of Ia terminals and postactivation depression at the Ia fibre-motor neuron (MN) synapses were compared in the upper and lower limbs of both sides in subjects from different populations: 49 spastic patients with hemiplegia [mainly with a lesion in the middle cerebral artery (MCA) area], two tetraplegics and 35 healthy subjects. Presynaptic inhibition was assessed using D1 inhibition of the soleus and the flexor carpi radialis (FCR) H reflexes elicited by electrical stimuli applied to the nerve supplying antagonistic muscles, and postactivation depression was explored by varying the time interval between two consecutive H reflexes. In normal subjects no right-left asymmetry was found in the amount of presynaptic Ia inhibition, homosynaptic depression or the H(max)/M(max) ratio. In the hemiplegic side of patients with MCA area lesions, the H(max)/M(max) ratio was significantly increased in the soleus but not in the FCR. Presynaptic inhibition of Ia terminals, which was significantly reduced at the cervical level on the hemiplegic side (and also, but to a lesser extent, on the unaffected side), was unchanged at the lumbar level. Homosynaptic depression was similarly reduced at the cervical and lumbar levels on the hemiplegic side but not modified on the unaffected side. It is argued that the decrease in presynaptic inhibition of Ia terminals is more a correlate of spasticity than a mechanism underlying it. The decrease in postactivation depression, which very probably contributes to the exaggeration of the stretch reflex characterizing spasticity, might be a consequence of the changes in the pattern of activation of Ia afferents and MNs following the motor impairment.

Adult↗

PubMed1999

Handedness-related asymmetry in transmission in a system of human cervical premotoneurones.

The possibility was investigated that human handedness is associated with an asymmetrical cortical and/or peripheral control of the cervical premotoneurones (PreMNs) that have been shown to mediate part of the descending command to motoneurones of forearm muscles. Heteronymous facilitation evoked in the ongoing voluntary extensor carpi radialis (ECR) electromyographic activity (EMG) by weak (0.8 times motor threshold) stimulation of the musculo-cutaneous (MC) nerve was assessed during tonic co-contraction of biceps and ECR. Suppression evoked by stimulation of a cutaneous nerve (superficial radial, SR) at 4 times perception threshold in both the voluntary EMG and in the motor evoked potential (MEP) elicited in ECR by transcranial magnetic stimulation (TMS) was investigated during isolated ECR contraction. Measurements were performed within time windows or at interstimulus intervals where peripheral and cortical inputs may interact at the level of PreMNs. Results obtained on both sides were compared in consistent right- and left-handers. MC-induced facilitation of the voluntary ECR EMG was significantly larger on the preferred side, whereas there was no asymmetry in the SR-evoked depression of the ongoing ECR EMG. In addition, the suppression of the ECR MEP by the same SR stimulation was more pronounced on the dominant side during unilateral, but not during bilateral, ECR contraction. It is argued that (1) asymmetry in MC-induced facilitation of the voluntary EMG reflects a greater efficiency of the peripheral heteronymous volley in facilitating PreMNs on the dominant side; (2) asymmetry in SR-induced suppression of the MEP during unilateral ECR contraction, which is not paralleled by a similar asymmetry of voluntary EMG suppression, reflects a higher excitability of cortical neurones controlling inhibitory spinal pathways to cervical PreMNs on the preferred side.

Adult↗

PubMed1999

Perception of self-generated movement following left parietal lesion.

Three apraxic patients with lesions in the left parietal cortex were required to execute finger movements with either hand, while the visual feedback they received about the movement was manipulated systematically. We used a device which allowed us to present on a video monitor either the patient's hand or the examiner's hand simultaneously performing an identical or a different movement. In each trial, patients were required to decide whether the hand shown on the screen was their own or not. Hand movements produced in response to verbal command included simple (single-finger extension) and complex gestures (multi-finger extension). Ownership judgements were analysed and compared with those produced by six normal controls and two non-apraxic neurological patients. Apraxic patients and controls accurately recognized their own hand on the screen (own movement condition) and correctly identified the viewed hand as the examiner's when it performed a movement different from their own movement (incongruent movement condition). However, when the viewed hand was the examiner's hand executing their own movement (congruent movement condition), apraxic patients were significantly more impaired than controls. When the results were analysed as a function of gesture type, the number of correct responses was significantly lower for apraxic patients with respect to controls only for complex gestures. Interestingly, when patients executed the finger gestures inaccurately, they still failed to recognize the examiner's hand as alien, and claimed that the correct movement presented on the screen was their own. These results confirm that parietal lesions alter the representational aspects of gestures, and suggest a failure in evaluating and comparing internal and external feedback about movement. We conclude that the parietal cortex plays an important role in generating and maintaining a kinaesthetic model of ongoing movements.

Aged↗