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Jean-Marie Annoni

Publications and source records attributed to Jean-Marie Annoni.

17 recordsLinked to original sources
PubMed2007

Histamine H1 blocker hydroxyzine improves sleep in patients with cirrhosis and minimal hepatic encephalopathy: a randomized controlled pilot trial.

OBJECTIVES: Sleep difficulty is common in minimal hepatic encephalopathy (HE) and the mechanisms are not fully elucidated. Dysregulated histamine neurotransmission is associated with an altered circadian rhythmicity that is partially restored following central histamine H1 receptor blockade in cirrhotic animals. We studied the effects of the histamine H1 blocker hydroxyzine in sleep alterations in patients with cirrhosis in a double-blind, randomized controlled fashion. METHODS: A total of 35 patients (age 56 yr [36-69], Pugh's score 9 [7-12], portosystemic shunt: N = 7) with minimal HE and long-standing sleep difficulties (8 months [4-48]) and free from benzodiazepines were randomized to hydroxyzine 25 mg at bedtime (N = 17) or placebo (N = 18) for a 10-day period. Measurements of sleep behavior using visual analog scale and wrist actigraphy, neuropsychological tests, and protein s100beta serum levels were performed at baseline and at day 10. RESULTS: Subjective improvement in sleep was observed in 40% of hydroxyzine-treated patients but in none receiving placebo (P < 0.04). Objectively, 65% of hydroxyzine-treated patients versus 25% of patients under placebo had a >or=30% increase in sleep efficiency as measured by wrist actigraphy (P < 0.04). Neuropsychological tests (Z scores) and protein s100beta levels remained statistically unchanged in both groups. One patient developed an acute episode of encephalopathy reversible upon cessation of hydroxyzine. CONCLUSIONS: In contrast to placebo, hydroxyzine 25 mg at bedtime improved sleep behavior (subjectively and using wrist actigraphy) in patients with cirrhosis and minimal HE. The risk of precipitating overt HE warrants some caution when prescribing this drug.

Adult↗
PubMed2007

Rhyme processing in the brain: an ERP mapping study.

The event-related potential (ERP) N450 component has been described in rhyme detection tasks as a negative response elicited by non-rhyming words in comparison to rhyming ones. This response, which peaked around 450 ms over the midline and right hemisphere recording sites, has been subsequently suggested to start already at approximately 300 ms. Moreover, although, the phonological N450 has first been linked to the semantic N400 component, its cognitive nature and cerebral origin remained debated. In this study, we re-investigated the time course of the electrophysiological responses to rhyming and non-rhyming words and estimated their cerebral generators using source localization methods. Waveform analysis showed that, prior to the N450 response to non-rhyming, a slightly earlier negativity characterized the rhyming condition over left fronto-temporal electrodes and peaked at approximately 350 ms. The analysis of the ERP map series in terms of functional microstates revealed a specific map segment in the rhyming condition and another one in the non-rhyming condition. Source localization indicated that the rhyming-elicited microstate engaged predominantly left frontal and temporal areas while the non rhyming-specific response recruited temporal and parietal regions bilaterally. Our results suggest that, similar to the N400 component that is also induced by mismatch contexts, the N450 might rely on temporal generators.

Adult↗
PubMed2006

Near-death experience in a boy undergoing uneventful elective surgery under general anesthesia.

Near-death experience (NDE) is a complex subjective experience, which may include affective elements such as a sense of peacefulness, paranormal components such as a sensation of floating out of the body, and a perception of being in a dark tunnel and seeing a brilliant light. It is usually reported to occur in association with a wide range of life-threatening situations, as for instance, cardiopulmonary resuscitation. We report on an episode of NDE that occurred in a 12-year-old boy who underwent a general anesthesia for an elective uncomplicated surgery. To our knowledge, this is the first case of NDE in a child that has been reported in this context.

Anesthesia, General↗
PubMed2005

Cognition-enhancing effects of donepezil in traumatic brain injury.

The purpose of this study was to investigate the effects of donepezil, a cholinergic agent, on chronic cognitive impairment due to traumatic brain injury (TBI). Chronic patients underwent two standardized neuropsychological evaluations--one before and the other 3 months following treatment with donepezil. Together with global inventories that appraised behaviour, fatigue, anxiety and depression, these evaluations also assessed executive functioning, memory and attention. Of the 10 patients who followed the therapy, 8 reported subjective improvement in at least one cognitive domain following therapy and most of them reported better functioning in everyday activities. This effect was supported by a slight global improvement when considering the global score of the different affectivo-behavioural scales. At the neuropsychological level, although we could observe a slight improvement in the majority of the considered tests, significant positive changes were mainly found in tests assessing speed of processing, learning and divided attention. These findings suggest that donepezil may lead to better general functioning and improve attentional skills in patients with chronic TBI.

Adult↗
PubMed2004

Transient crossed aphasia evidenced by functional brain imagery.

Crossed aphasia refers to language deficits induced by unilateral right hemisphere injuries in right-handed people who had no previous history of brain damage. One of the intriguing questions concerning crossed aphasia is the atypical language representation in the brain. In this respect, fMRI is a valuable tool for understanding the neural basis of crossed aphasia. Here, we used neuropsychological and fMRI language tasks in a right-handed subject who presented a crossed aphasia due to a right frontal meningioma. fMRI maps from two language tasks showed bilateral patterns of activation. In the light of previous studies reporting much frequent bilateral than exclusive right hemisphere representations, we hypothesise that some crossed aphasia cases could occur in subjects with bilateral language representation.

Aphasia↗
PubMed2004

Altered decision-making in multiple sclerosis: a sign of impaired emotional reactivity?

We assessed decision-making capacity and emotional reactivity in 20 patients with multiple sclerosis (MS) and in 16 healthy subjects using the Gambling Task (GT), a model of real-life decision making, and the skin conductance response (SCR). Demographic, neurological, affective, and cognitive parameters were analyzed in MS patients for their effect on decision-making performance. MS patients persisted longer (slope, -3.6%) than the comparison group (slope, -6.4%) in making disadvantageous choices as the GT progressed (p < 0.001), suggesting significant slower learning in MS. Patients with higher Expanded Disability Status Scale scores (EDSS >2.0) showed a different pattern of impairment in the learning process compared with patients with lower functional impairment (EDSS </=2.0). This slower learning was associated with impaired emotional reactivity (anticipatory SCR 3.9 vs 6.1 microSiemens [microS] for patients vs the comparison group, p < 0.0001; post-choice SCR 3.9 vs 6.2 microS, p < 0.0001), but not with executive dysfunction. Impaired emotional dimensions of behavior (assessed using the Dysexecutive Questionnaire, p < 0.002) also correlated with slower learning. Given the considerable consequences that impaired decision making can have on daily life, we suggest that this factor may contribute to handicap and altered quality of life secondary to MS and is dependent on emotional experience. Ann Neurol 2004.

Adult↗
PubMed2004

Variability of fMRI activation during a phonological and semantic language task in healthy subjects.

Assessing inter-individual variability of functional activations is of practical importance in the use of functional magnetic resonance imaging (fMRI) in a clinical context. In this fMRI study we addressed this issue in 30 right-handed, healthy subjects using rhyme detection (phonologic) and semantic categorization tasks. Significant activations, found mainly in the left hemisphere, concerned the inferior frontal gyrus, the superior/middle temporal gyri, the prefrontal cortex, the inferior parietal lobe, the superior parietal lobule/superior occipital gyrus, the pre-central gyrus, and the supplementary motor area. Intensity/spatial analysis comparing activations in both tasks revealed an increased involvement of frontal regions in the semantic task and of temporo-parietal regions in the phonologic task. The frequency of activation analyzed in nine regional subdivisions revealed a high inter-subject variability but showed that the most frequently activated regions were the inferior frontal gyrus and the prefrontal cortex. Laterality indices, strongly lateralizing in both tasks, were slightly higher in the semantic (0.76 +/- 0.19) than the phonologic task (0.66 +/- 0.27). Frontal dominance indices (a measure of frontal vs. posterior left hemisphere dominance) indicated more robust frontal activations in the semantic than the phonologic task. Our study allowed the characterization of the most frequently involved foci in two language tasks and showed that the combination of these tasks constitutes a suitable tool for determining language lateralization and for mapping major language areas.

Adult↗
PubMed2004

Persistent severe depressive episode with mood-congruent psychotic features associated with left temporal ischemia.

OBJECTIVE: The authors describe the case of a patient suffering from a persistent severe depressive episode with mood-congruent psychotic features following left temporal ischemia. BACKGROUND: Depression is a frequent disorder that may stem from psychosocial factors or occur after brain damage. Cases of poststroke depression with associated psychotic symptoms are rarely described in the literature, and, to our knowledge, no case of depression with psychotic symptoms in the presence of a focal lesion has yet been reported. METHOD: History included psychiatric, neurologic, and neuropsychological as well as EEG data and CT scan and magnetic resonance images. RESULTS AND CONCLUSIONS: Neurologic and psychiatric dimensions may be associated and difficult to disentangle, even when the patient presents the classic symptoms of a depressive disorder. This case underlines the importance of investigating possible neurologic signs or symptoms, even when the psychiatric presentation is prototypical of a determined mental disorder. This may be crucial for the patient's evolution.

Brain Ischemia↗
PubMed2003

Sound recognition and localization in man: specialized cortical networks and effects of acute circumscribed lesions.

Functional imaging studies have shown that information relevant to sound recognition and sound localization are processed in anatomically distinct cortical networks. We have investigated the functional organization of these specialized networks by evaluating acute effects of circumscribed hemispheric lesions. Thirty patients with a primary unilateral hemispheric lesion, 15 with right-hemispheric damage (RHD) and 15 with left-hemispheric damage (LHD), were evaluated for their capacity to recognise environmental sounds, to localize sounds in space and to perceive sound motion. One patient with RHD and 2 with LHD had a selective deficit in sound recognition; 3 with RHD a selective deficit in sound localization; 2 with LHD a selective deficit in sound motion perception; 4 with RHD and 3 with LHD a combined deficit of sound localization and motion perception; 2 with RHD and 1 with LHD a combined deficit of sound recognition and motion perception; and 1 with LHD a combined deficit of sound recognition, localization and motion perception. Five patients with RHD and 6 with LHD had normal performance in all three domains. Deficient performance in sound recognition, sound localization and/or sound motion perception was always associated with a lesion that involved the shared auditory structures and the specialized What and/or Where networks, while normal performance was associated with lesions within or outside these territories. Thus, damage to regions known to be involved in auditory processing in normal subjects is necessary, but not sufficient for a deficit to occur. Lesions of a specialized network was not always associated with the corresponding deficit. Conversely, specific deficits tended not be associated predominantly with lesions of the corresponding network; e.g. deficits in auditory spatial tasks were observed in patients whose lesions involved to a larger extent the shared auditory structures and the specialized What network than the specialized Where network, and deficits in sound recognition in patients whose lesions involved mostly the shared auditory structures and to a varying degree the specialized What network. The human auditory cortex consists of functionally defined auditory areas, whose intrinsic organization is currently not understood. In particular, areas involved in the What and Where pathways can be conceived as: (1) specialized regions, in which lesions cause dysfunction limited to the damaged part; observed deficits should be then related to the specialization of the damaged region and their magnitude to the extent of the damage; or (2) specialized networks, in which lesions cause dysfunction that may spread over the two specialized networks; observed deficits may then not be related to the damaged region and their magnitude not proportional to the extent of the damage. Our results support strongly the network hypothesis.

Acute Disease↗
PubMed2003

Chronic cognitive impairment following laterothalamic infarcts: a study of 9 cases.

BACKGROUND: The occlusion of the lateral thalamic arteries leads to infarcts of ventrolateral thalamic nuclei, the ventroposterior nucleus, and the rostrolateral part of pulvinar, and produces hemisensory loss with or without hemiataxia. Cognitive impairment after such strokes has not been systematically studied. OBJECTIVE: To determine the nature and the extent of long-lasting cognitive deficits following lateral thalamic strokes. DESIGN: Case series. SETTING: Neurology department, Lausanne University Hospital, Lausanne, Switzerland. PATIENTS: Nine patients with hemisensory loss due to an isolated laterothalamic infarct. MAIN OUTCOME MEASURES: Three to 6 months after stroke onset, standard neuropsychologic evaluation, including testing of language, ideomotor and constructive praxis, visual gnosis, spatial attention, learning abilities, and executive functions. RESULTS: Six of 9 patients showed some degree of cognitive impairment. Executive functions tasks, particularly verbal fluency, were impaired in 5 patients (4 with right and 1 with left lesion). Learning and delayed recall in visuospatial and verbal tasks, but not in recognition, were impaired in 3 patients (2 with right and 1 with left lesion). Difficulties in visual gnosia were observed in 1 patient with right lesion while word-finding difficulties were observed in 1 patient with left lesion. CONCLUSIONS: Our observations show that while learning, naming, and gnosic difficulties fit with the classical verbal/nonverbal dichotomy (left and right hemisphere, respectively), executive dysfunctions, including verbal fluency tasks, were more dominant after right thalamic infarcts. Although the observed deficits appeared to be less severe than those generally found with dorsomedial and polar thalamic strokes, the dominance of executive dysfunction suggests that ventrolateral thalamic lesions may disrupt frontothalamic subcortical loops.

Aged↗
PubMed2003

Decoupling of autonomic and cognitive emotional reactions after cerebellar stroke.

Emotional blunting can be found after cerebellar lesions. However, the mechanism of such a modification is not clear. We present a patient with emotional flattening and increased risk taking after left cerebellar infarct who had an impaired autonomic reactivity to negative as compared with positive reinforcement. This impairment was demonstrated by the patient's undifferentiated skin conductance responses to negative and positive reinforcement, whereas controls produced larger skin conductance responses after negative feedback. The cooccurrence of emotional flattening and undifferentiated autonomic reactions to positively and negatively valenced stimuli strengthens the role of the cerebellum in the modulation of the autonomic responses.

Affect↗
PubMed2003

Processing of semantic categorical and associative relations: an ERP mapping study.

Brain imaging studies have repeatedly shown a dominant involvement of the left hemisphere (LH) in the processing of semantic information. However, some behavioural studies have suggested that the right hemisphere (RH) also processes lexico-semantic information although in a qualitatively different way. More specifically, it has been proposed that the LH shows a greater sensitivity to categorical (CR, or intraconceptual) relationships, while the RH appears more sensitive to associative (AR, or interconceptual) ones. Using semantically unrelated and related word pairs comprised of CR and AR, our aim in this study was to verify the involvement of the RH in the processing of associative relationships. Strength-independent topographical analysis of ERP map series using temporal segmentation procedures showed the same sequence of eight stable map segments in CR and AR conditions. Statistical analysis revealed no difference between conditions either in terms of duration or in terms of time of occurrence of the segmentation maps. However, field strength comparisons between the two conditions using the global field power measure at each time point revealed higher field strength in CR than in AR condition between 300 and 330 ms. Distributed source localisation showed a similar pattern of activation during this time period, involving predominantly left frontal regions. Nevertheless, the strength of the source found in the left medial frontal gyrus differed between CR than AR conditions, thus explaining the differences observed in field strength. Our data suggest that the processing of CR and AR words depend on the same neural network in the LH.

Adolescent↗
PubMed2003

Number processing after stroke: anatomoclinical correlations in oral and written codes.

Calculation and number-processing abilities were studied in 49 patients with chronic single vascular brain lesions by means of a standardized multitask assessment battery (EC301), as well as through other tasks, testing functions thought to be implicated in calculation such as language, visuo-perceptive abilities, verbal and spatial working memory, planning, and attention. The results show that (1) lesions involving parietal areas-particularly left parietal lesions-are prone to alter calculation processing. A more detailed analysis showed that patients with lesions involving left parietal areas were impaired in both digital (i.e., comprehension and production of numbers written in Arabic code) and oral (i.e., comprehension and production of numbers heard or expressed orally) processing while lesions involving right parietal areas lead to an impairment in digital processing only. However, linguistically related alphanumerical processing (i.e., comprehension and production of numbers written orthographically) was not influenced by parietal lesions. (2) Semantic representations (knowledge of the magnitude related to a given number) as well as rote arithmetical knowledge are also impaired following damage to parietal and particularly left parietal lesions, suggesting that these areas are also implicated in magnitude comparisons and in the retrieval of arithmetical facts. (3) Performance in calculation is highly correlated with language. (4) Moreover, we found a highly significant correlation between performances in oral calculation and verbal working memory, and between written-digit calculation and visuospatial working memory. Performances in regard to visuo-perceptive abilities, planning, and attention were less consistently correlated with calculation. These results stress the close correlation, but relative independence between calculation and language, as well as a dissociated sensitivity of oral and digital processing to brain lesions.

Adult↗
PubMed2003

[Neuropsychological test in daily practice].

Neuropsychology is a scientific discipline, born in the XIX century, and bridges the fields of neurology and psychology. Neuropsychologists apply scientific knowledge about the relationship between brain function and mental performances. The major clinical role of a neuropsychological evaluation is to help to establish medical and functional diagnosis in patients (adults or infants) with different neurological pathologies such as stroke, traumatic brain injury, dementia, epilepsy.... Such analysis necessitates accurate observation of behaviour and administration of tests of mental abilities (e.g. language, memory...). Test results can also help to clarify the nature of cognitive difficulties and to support the formulation of plans for neuropsychological therapy and functional adjustment in every day life.

Adult↗
PubMed2002

Dynamics of brain activation during an explicit word and image recognition task: an electrophysiological study.

Recent brain imaging studies suggest that semantic processing of words and images may share a common neural network, although modality-specific activation can also be observed. Other studies using event-related potentials (ERPs) report that brain responses to words and images may already differ at approximately 150 ms following stimulus presentation. The question thus remains, which differences are due to perceptual categorization processes and which differences are due to the semantic ones? Using ERP recordings and spatio-temporal source localization analysis, we investigated the dynamics of brain activation during a recognition task. The stimuli consisted of a randomized set of verbal (words vs. non-words) and pictorial items (line drawings of objects vs. scrambled drawings). After each stimulus, subjects had to decide whether it corresponds to a recognizable word or objects. ERP map series were first analyzed in terms of segments of quasi-stable map topography using a cluster analysis. This showed that verbal and pictorial stimuli elicited different field patterns in two time segments between approximately 190-400 ms. Before and after this period, map patterns were similar between verbal and pictorial conditions indicating that the same brain structures were engaged during the early and late steps of processing. Source localization analysis of map segments corresponding to the P100 and the N150 components first showed activation of posterior bilateral regions and then of left temporo-posterior areas. During the period differentiating conditions, other patterns of activation, involving mainly left anterior and posterior regions for words and bilateral posterior regions for images, were observed. These findings suggest that, while sharing an initial common network, recognition of verbal and pictorial stimuli subsequently engage different brain regions during time periods generally allocated to the semantic processing of stimuli.

Acoustic Stimulation↗
PubMedDate not supplied

Emotional disturbances after stroke.

Impairment after stroke may have acute and long-lasting psychological implications. Additionally, organic brain dysfunction also appears to play an important role in poststroke affective modifications. Emotional state is multidetermined and can be specifically modified by alteration of some brain networks. This article illustrates a certain number of acute and more chronic emotional disturbances after stroke, such as mood disorders, emotional dyscontrol, and modification of emotional experiences. Some neural mechanisms implicated in these modifications are discussed. The main modifications described are depression anxiety, psychosis, modification of emotional experience, and fatigue.

Affective Symptoms↗