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Vocal emotion recognition, a key determinant to analyzing a speaker’s emotional state, is known to be impaired following cerebellar dysfunctions. Nevertheless, its possible functional integration in the large-scale brain network subtending emotional prosody recognition has yet to be explored. We administered an emotional prosody recognition task to patients with right versus left-hemispheric cerebellar lesions and a group of matched controls. We explored the lesional correlates of vocal emotion recognition in patients through a network-based analysis by combining a neuropsychological approach for lesion mapping with normative brain connectome data. Results revealed impaired recognition among patients for neutral or negative prosody, with poorer sadness recognition performances by patients with right cerebellar lesion. Network-based lesion-symptom mapping revealed that sadness recognition performances were linked to a network connecting the cerebellum with left frontal, temporal, and parietal cortices. Moreover, when focusing solely on a subgroup of patients with right cerebellar damage, sadness recognition performances were associated with a more restricted network connecting the cerebellum to the left parietal lobe. As the left hemisphere is known to be crucial for the processing of short segmental information, these results suggest that a corticocerebellar network operates on a fine temporal scale during vocal emotion decoding.

Unilateral spatial neglect is a neuropsychological syndrome commonly observed after stroke and defined by the inability to attend or respond to contralesional stimuli. Typically, symptoms are assessed using clinical tests that rely upon visual/perceptual abilities. However, neglect may affect high-level representations controlling attention in other modalities as well. Here we developed a novel manual exploration test using a touch screen computer to quantify spatial search behaviour without visual input. Twelve chronic stroke patients with left neglect and 27 patients without neglect (based on clinical tests) completed our task. Four of the 12 "neglect" patients exhibited clear signs of neglect on our task as compared to "non-neglect" patients and healthy controls, and six other patients (from both groups) also demonstrated signs of neglect compared to healthy controls only. While some patients made asymmetrical responses on only one task, generally, patients with the strongest neglect performed poorly on multiple tasks. This suggests that representations associated with different modalities may be affected separately, but that severe forms of neglect are more likely related to damage in a common underlying representation. Our manual exploration task is easy to administer and can be added to standard neglect screenings to better measure symptom severity.

There is growing evidence that both the basal ganglia and the cerebellum play functional roles in emotion processing, either directly or indirectly, through their connections with cortical and subcortical structures. However, the lateralization of this complex processing in emotion recognition remains unclear. To address this issue, we investigated emotional prosody recognition in individuals with Parkinson’s disease (model of basal ganglia dysfunction) or cerebellar stroke patients, as well as in matched healthy controls (n = 24 in each group). We analysed performances according to the lateralization of the predominant brain degeneration/lesion. Results showed that a right (basal ganglia and cerebellar) hemispheric dysfunction was likely to induce greater deficits than a left one. Moreover, deficits following left hemispheric dysfunction were only observed in cerebellar stroke patients, and these deficits resembled those observed after degeneration of the right basal ganglia. Additional analyses taking disease duration / time since stroke into consideration revealed a worsening of performances in patients with predominantly right-sided lesions over time. These results point to the differential, but complementary, involvement of the cerebellum and basal ganglia in emotional prosody decoding, with a probable hemispheric specialization according to the level of cognitive integration.

The effectiveness of EEG-neurofeedback (EEG-NFB) in modulating cognition has been the subject of much research for several years, particularly in relation to attentional functions in healthy subjects and those with attentional deficits. However, its effectiveness on sports performance remains poorly studied and its use is not widely practised among athletes, notably because of its accessibility and questionable effectiveness. The aim of this study is to show that this technology can be accessible, and that Alpha EEG-NFB is immediately effective. Fifteen professional soccer players took part in this study. Using a novel EEG headset that can be installed in less than one minute, and new processing software, the players performed two peripherical attentional tasks before and after, immediately and one month, a single Alpha EEG-NFB training session. The results showed a significant effect on both tasks immediately after EEG-NFB training, with a benefit of more than 30% and this performance continued after one month (20%). This study, the first to use this headset and software, shows that the improvement in sports performance can be related to cognitive performance, especially peripherical visual attentional functions. Furthermore, it demonstrates that the use of the EEG-NFB is accessible and effective for high-level athletes.

Recent findings indicate that synchronous neural activity at rest influences human performance in subsequent tasks. Synchronization can occur in form of phase coupling or amplitude correlation. It is unknown whether these coupling types have differing behavioral significance at rest. To address this, we performed resting-state electroencephalography (EEG) and source connectivity analysis in several populations of healthy subjects and patients with brain lesions. We systematically compared different types and frequencies of neural synchronization and investigated their association with behavioral performance in verbal and spatial attention tasks. Behavioral performance could be consistently predicted by two distinct resting-state coupling patterns: (1) amplitude envelope correlation of beta activity between homologous areas of both hemispheres, (2) lagged phase synchronization in EEG alpha activity between a brain area and the entire cortex. A disruption of these coupling patterns was also associated with neurological deficits in patients with stroke lesions. This suggests the existence of two distinct network systems responsible for resting-state integration. Lagged phase synchronization in the alpha band is associated with global interaction across networks while amplitude envelope correlation seems to be behaviorally relevant for interactions within networks and between hemispheres. These two coupling types may therefore provide complementary insights on brain physiology and pathology.

Spatial remapping implies the updating and maintaining of the spatial position of objects in successive visual images across time, despite their displacement on the retina due to eye movements. In the parietal cortex, the representation of spatial locations appears to be partly centered on gaze direction, and thus modulated by current eye-gaze position. It has been suggested that short-term memory for spatial locations across delays might be impaired in right brain-injured patients with left spatial neglect, but more so after rightward than leftward gaze shifts - an asymmetry attributed to a loss of spatial representations normally transferred from left to right hemisphere during remapping. Because several studies point to a strong link between attentional and oculomotor circuits in the brain, we hypothesized that similar remapping effects might result from attentional displacements without overt eye movements. We tested this hypothesis in right-brain damaged patients with and without left neglect in a visuo-spatial memory task. As predicted, neglect patients showed a selective deficit in location memory following an exogenous attentional shift caused by a brief flash in the periphery of their right (but not left) visual field. We conclude that an attentional displacement without eye movements is sufficient to remap spatial representations across hemifields, and that this process is impaired in neglect patients when a location has to be transferred to the neglected/left side relative to current gaze or attention focus. More generally, these results support the notion of neural overlap between oculomotor and attentional mechanisms, and confirm a role for impaired remapping in the neglect syndrome, wherein spatial representations of contralesional locations may fail to be maintained during active attentional behavior.

Prism adaptation (PA) is one of the few rehabilitation techniques for spatial neglect that directly targets physiological mechanisms underlying space representation, but its efficacy and neural mechanisms remain unresolved. Using PA and fMRI in patients with spatial neglect after an acute right-hemispheric stroke, we previously observed post-PA increases in activity in bilateral parietal, frontal, and occipital cortex during specific visuo-spatial tasks (bisection and visual search). However, given a key role of parietal areas for PA in healthy individuals, we hypothesized that such activation might differ according to the site of brain damage. We studied a group of 10 patients with focal right hemisphere stroke and spatial neglect at baseline and after PA, who were divided in two groups (5 patients with frontal and 5 patients with parietal strokes). We compared their behavioural performance and brain activation patterns during fMRI. At the behavioural level, frontal and parietal patients showed similar neglect signs on visuo-spatial tasks before PA, but frontal patients showed larger benefit from PA. Differences were also observed in cortical activity, with enhanced recruitment of right parietal areas in frontal patients and less consistent patterns in parietal patients. Furthermore, fMRI analysis during PA itself (divided in 5 successive periods) showed differential activations between group in anatomically preserved pathways, including occipital areas and cerebellum, that preceded changes in parietal areas and were specific to frontal patients. These data accord with the hypothesis that intact cerebello-parietal connections may underpin improvement of spatial neglect after PA. Altogether, these results provide important insights on brain networks involved in spatial cognition and may allow an optimal selection of patients benefiting from PA after right hemispheric stroke.

Stroke frequently produces attentional dysfunctions including symptoms of hemispatial neglect, which is characterized by a breakdown of awareness for the contralesional hemispace. Recent studies with functional MRI (fMRI) suggest that hemineglect patients display abnormal

Graphical abstract, Highlights • Patients with cerebellar stroke have deficits in emotional prosody recognition. • Patients with right-hemispheric lesions make more misattributions. • Emotion deficits correlate with lesions in right Lobules VIIb–VIII and Crus I–II. • Acoustic features explain a significant proportion of the variance. • The posterior cerebellar lobe is involved in both sensory and emotional processes., In recent years, there has been increasing evidence of cerebellar involvement in emotion processing. Difficulties in the recognition of emotion from voices (i.e., emotional prosody) have been observed following cerebellar stroke. However, the interplay between sensory and higher-order cognitive dysfunction in these deficits, as well as possible hemispheric specialization for emotional prosody processing, has yet to be elucidated. We investigated the emotional prosody recognition performances of patients with right versus left cerebellar lesions, as well as of matched controls, entering the acoustic features of the stimuli in our statistical model. We also explored the cerebellar lesion-behavior relationship, using voxel-based lesion-symptom mapping. Results revealed impairment of vocal emotion recognition in both patient subgroups, particularly for neutral or negative prosody, with a higher number of misattributions in patients with right-hemispheric stroke. Voxel-based lesion-symptom mapping showed that some emotional misattributions correlated with lesions in the right Lobules VIIb and VIII and right Crus I and II. Furthermore, a significant proportion of the variance in this misattribution was explained by acoustic features such as pitch, loudness, and spectral aspects. These results point to bilateral posterior cerebellar involvement in both the sensory and cognitive processing of emotions.

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Background and purpose In this study, the question of whether egocentric representation of space is impaired in chronic unilateral vestibulopathies was examined. The objective was to test current theories attributing a predominant role to vestibular afferents in spatial cognition and to assess whether representational neglect signs are common in peripheral vestibular loss. Methods The subjective straight-ahead (SSA) direction was investigated using a horizontal rod allowing the translation and rotation components of the body midline representation to be dissociated in 21 patients with unilateral vestibular loss (right, 13; left, eight) and in 12 healthy controls. Results Compared to the controls, the patients with unilateral vestibulopathy showed a translation bias of their SSA, without rotation bias. The translation bias was not lateralized towards the lesioned side as typically found for biases reported after unilateral vestibular loss. Rather, the SSA bias was rightward whatever the side of the vestibular loss. The translation bias correlated with the vestibular loss, as measured by caloric response and vestibulo-ocular reflex gain, but not with the subjective visual vertical or the residual spontaneous nystagmus. Conclusion The present data suggest that the dysfunctions of neural networks involved in egocentred and allocentred representations of space are differentially compensated for in unilateral vestibular defective patients. In particular, they suggest that asymmetrical vestibular inputs to cortical regions lead to representational spatial disturbances as does defective cortical processing of vestibular inputs in spatial neglect after right hemisphere stroke. They also highlight the predominant role of symmetrical and unaltered vestibular inputs in spatial cognition.

Au cours du 3ème Congrès National de Neuropsychologie Clinique (CNNC) a eu lieu en France la première rencontre entre les représentants des associations de psychologues spécialisés en neuropsychologie issus de quatre territoires francophones : la Belgique, la France, la province du Québec et la Suisse. Ces associations sont impliquées dans la promotion et la reconnaissance de la spécialité dans leurs régions respectives, à savoir l’Union Professionnelle des Psychologues Cliniciens Francophones pour la Belgique (UPPCF-pôle neuropsychologie), l’Organisation Française des Psychologues spécialisés en Neuropsychologie (OFPN), l’Association Québécoise des Neuropsychologues (AQNP) et l’Association Suisse des Neuropsychologues (ASNP). L’objectif principal de cette rencontre était de profiter de ce rassemblement inédit pour pointer les similitudes, les différences, les points d'intérêt particuliers et les perspectives d’amélioration vers lesquelles faire converger les pratiques des psychologues francophones spécialisés en neuropsychologie et favoriser leur reconnaissance. Après une brève introduction présentant l’essor de la neuropsychologie de chaque pays, plusieurs thèmes ont été abordés : formation, statut, reconnaissance, pratiques professionnelles, enjeux et perspectives. L’intervention s’est conclue par le constat d’un nombre important de similarités dans les problématiques rencontrées, ainsi qu’une réelle volonté de mutualiser les démarches et réalisations nationales. Cet élan a permis de formaliser la création symbolique d’une Fédération Internationale des associations de Neuropsychologues Francophones (FINF).

Objective Apathy-the most common behavioral disturbance in idiopathic normal pressure hydrocephalus (iNPH)-is associated with poor gait, but the role of apathy on gait improvement after cerebrospinal fluid (CSF) tapping has not been studied yet. This study aims to compare gait improvement after CSF tapping in iNPH patients with and without apathy. Methods Stride time variability (STV), a marker of higher level of gait control, was measured in 33 iNPH patients (78.4 ± 5.7 years; 36.4% women) with an optoelectronic system during usual walking (single task) and during walking while dual tasking of counting and verbal fluency before and 24 hours after CSF tapping. Apathy was defined by a score ≥14 on the Starkstein apathy scale. Results Apathy was present in 60.6% of patients. Cerebrospinal fluid tapping led to greater improvement of STV (ie, decrease) during dual-task walking (and more specifically categorical verbal fluency) in apathetic compared to nonapathetic patients (-44.7 ± 58.1% versus +4.24 ± 67.6%, respectively; P = .040), even after adjusting for age and depressive symptoms. More severe apathy was correlated with better STV improvement while dual tasking (categorical verbal fluency) after CSF tapping (r = -0.412; P-value = 0.021), while it was not correlated with improvement on executive tests. Conclusions Our findings suggest that the presence of apathy is a predictor of better outcomes of gait disorders after CSF tapping in patients with iNPH.

Background Individuals with Williams Syndrome (WS) are known to have particular difficulties when performing visuo-spatial tasks, which could be related to their difficulties in using a specific reference system to determine spatial relations. The aim of the present study was to assess the internal representation of the body's sagittal plane, which is an important benchmark for an egocentric frame of reference. Method The results of 18 WS individuals (mean age = 20.5 ± 9.2 years) on the subjective straight ahead (SSA) task were compared with those of two healthy control groups composed of 36 participants matched on chronological age matched on chronological age (CA) and 30 young children matched on non-verbal intellectual ability (YC). Results Individuals with WS showed a significant left deviation on the SSA body's sagittal plane representation compared with the chronological age control group and a marginal left deviation compared with the young children control group. A comparison with the objective SA (0°) showed a significant leftward deviation in the WS group but not in the two control groups. Conclusions Individuals with WS showed a significant leftward deviation in the SSA task. This bias of the body's longitudinal axe representation could have a negative impact on the use of an egocentric reference system, which could be the cause for their difficulties in defining spatial relations (e.g. location and orientation) necessary for performing spatial tasks.

It is debated whether the amygdala is critical for the emotional modulation of attention. While some studies show reduced attentional benefits for emotional stimuli in amygdala-damaged patients, others report preserved emotional effects. Various factors may account for these discrepant findings, including the temporal onset of the lesion, the completeness and severity of tissue damage, or the extent of neural plasticity and compensatory mechanisms, among others. Here, we investigated a rare patient with focal acute destruction of bilateral amygdala and adjacent hippocampal structures after late-onset herpetic encephalitis in adulthood. We compared her performance in two classic visual attention paradigms with that of healthy controls. First, we tested for any emotional advantage during an attentional blink task. Whereas controls showed better report of fearful and happy than neutral faces on trials with short lags between targets, the patient showed no emotional advantage, but also globally reduced report rates for all faces. Second, to ensure that memory disturbance due to hippocampal damage would not interfere with report performance, we also used a visual search task with either emotionally or visually salient face targets. Although the patient still exhibited efficient guided search for visually salient, non-emotional faces, her search slopes for emotional versus neutral faces showed no comparable benefit. In both tasks, however, changes in the patient predominated for happy more than fear stimuli, despite her normal explicit recognition of happy expressions. Our results provide new support for a causal role of the amygdala in emotional facilitation of visual attention, especially under conditions of increasing task-demands, and not limited to negative information. In addition, our data suggest that such deficits may not be amenable to plasticity and compensation, perhaps due to sudden and late-onset damage occurring in adulthood.

BACKGROUND Recently, a study using the subjective straight-ahead task showed that individuals with Williams syndrome (WS) present a bias in the representation of body perception. The aim of the present study is to examine the horizontal midline body representation in WS participants using the bisection line task, which is an important benchmark for an egocentric frame of reference. METHOD Fifteen WS participants (mean age = 21.7 ± 9.5 years) were compared with two typical development control groups: one composed of 15 participants matched on chronological age and one composed of 15 children matched on mental age. The task consisted of dividing each line in a series of 18 lines into two equal halves by drawing a vertical mark with a pencil in the centre of the line. RESULTS Individuals with WS presented a significant leftward bias in comparison to mental age and chronological age groups. CONCLUSIONS The leftward deviation in WS could be linked to the body representation bias and difficulties in the development of the egocentric reference system. An early detection of such deviation should help in the development of targeted interventions for WS individuals to improve visual-spatial skills and learning.

While the role of the cerebellum in emotion recognition has been explored with facial expressions, its involvement in the auditory modality (i.e., emotional prosody) remains to be demonstrated. The present study investigated the recognition of emotional prosody in 15 patients with chronic cerebellar ischaemic stroke and 15 matched healthy controls, using a validated task, as well as clinical, motor, neuropsychological, and psychiatric assessments. We explored the cerebellar lesion-behaviour relationship using voxel-based lesion-symptom mapping. Results showed a significant difference between the stroke and healthy control groups, with patients giving erroneous ratings on the Surprise scale when they listened to fearful stimuli. Moreover, voxel-based lesion-symptom mapping revealed that these emotional misattributions correlated with lesions in right Lobules VIIb, VIIIa,b and IX. Interestingly, the posterior cerebellum has previously been found to be involved in affective processing, and Lobule VIIb in rhythm discrimination. These results point to the cerebellum’s functional involvement in vocal emotion decoding.

BACKGROUND Gait impairment is observed in early stages of dementia, such as mild cognitive impairment (MCI), and is associated with morphological brain volume changes like atrophy. OBJECTIVE This study aims to characterize the brain's grey matter (GM) volume covariance associated with gait speed in patients with amnestic mild cognitive impairment (aMCI) and non-amnestic MCI (naMCI). METHODS Gait speed was measured in 171 patients with MCI (age 72.0±5.1; 36.8% female; 41 with aMCI and 130 naMCI) at normal and rapid gait speeds. Brain GM covariance networks were computed using voxel-based morphometry, using the main neural correlates of gait speed in each group and for each walking condition as seed regions. RESULTS Normal gait speed correlated with GM volume in the left frontal cortex in patients with aMCI, and in bilateral caudate and left putamen in those with naMCI. Rapid gait speed correlated with GM volume in the bilateral caudate and right cerebellum in naMCI, but without any GM region in aMCI. For normal gait speed, the left caudate nucleus volume in naMCI covaried with subcortico-frontal regions, while the left frontal cortex covaried with cortical regions involving the frontal cortex in aMCI. For rapid gait speed, subcortico-frontal regions were similar as for normal speed in naMCI. CONCLUSION Brain GM volume covariance associated with gait speed varies according to the type of MCI; it involved subcortico-frontal regions for patients with naMCI and the frontal cortex in those with aMCI.

Remapping is a process that updates visual information in internal spatial representations across eye movements, allowing for stable perception of the environment. Previous work has demonstrated visual remapping activity in parietal cortex during saccades, but it remains unclear whether remapping is triggered by overt saccades only (or by attentional shifts also), and whether it engages parietal areas only (or other cortical areas). Here, we used fMRI to investigate spatial remapping during two visuospatial memory tasks requiring either overt (accompanied by a saccade) or covert (with central fixation) attention shifts to peripheral distracters. Participants had to remember the position and color of a lateralized dot during a saccade or attention shift, requiring them to update the dot position in memory, and then indicate if a second dot matched the first. Differential activation patterns were observed within parietal cortex as a function of the different visual, motor, and interhemispheric remapping demands in the saccade task, presumably mediating the maintenance of spatial position in perceptual and motor maps. Remapping engaged parietal areas adjacent to, but not overlapping with, those activated by saccade execution, while it did not engage the frontal eye fields, pointing to distinct neural substrates for ocular motor and spatial updating processes. No differential activation related to remapping was found during the covert attention shift task, suggesting that this condition did not necessitate the same remapping as the saccade condition. Overall these results further elucidate the mechanisms of spatial remapping in human parietal cortex and their relationship with attention processing and ocular motor behavior, with implications for understanding visuospatial attention deficits in hemispatial neglect.

Objective: Unilateral spatial neglect is a multi-faceted syndrome that arises from brain lesions, typically in the right hemisphere, and is characterized by the failure to attend or respond to stimuli in contralesional space. Here, we expand on the proposal that one deficit contributing to the diverse symptoms in neglect involves spatial remapping processes. Spatial remapping is required to maintain a stable visual representation despite frequent eye movements that change the retinal image. Neglect patients' lesions may disrupt the transfer of this representation across saccades, resulting in the loss of spatial information in working memory or even awareness of an object's presence. Method: In this review, we will characterize the neglect syndrome and its anatomical origins, describe spatial remapping in healthy individuals, then focus on how impairments of remapping and spatial working memory could contribute to some reported neglect symptoms. Finally, we will discuss the effectiveness of a rehabilitation method known as prism adaptation for alleviating visual spatial symptoms in neglect patients in relation to spatial remapping performance. Conclusions: The heterogeneity of spatial neglect makes it difficult to pinpoint a single underlying dysfunction or causal lesion. Given the number of brain regions that may be damaged across neglect patients, it is likely that many different processes contribute to the manifested attentional symptoms. In this review, we highlight the role of spatial remapping mechanisms subserved by posterior parietal cortex as one of the underlying deficits leading to visual spatial neglect.

Introduction La stabilite posturale diminuant avec l’âge, les personnes âgees ont de plus en plus de difficulte a realiser deux tâches simultanement. En effet, l’augmentation du controle moteur et sensoriel pour le maintien de l’equilibre reduit les capacites cognitives, notamment attentionnelles lors de la realisation de la seconde tâche (Shumway-Cook et Woollacott, 2000). Au cours de la visite d’un musee, les visiteurs vont mobiliser leurs ressources attentionnelles de maniere plus intense dans cet environnement nouveau, lors de la decouverte des œuvres, pouvant avoir des repercussions sur leurs stabilites posturales. L’objectif de notre travail est de quantifier les performances mnesiques du visiteur en lien avec la posture la plus optimale durant la visite museale. Materiel et methode Vingt personnes âges de plus de 60 ans observerons de maniere attentive 3 œuvres du musee des Beaux-Arts de Montreal dans 3 positions differentes : assise, debout et en marche. Les donnees cinetiques seront recueillies par une plateforme de force et les donnees cinematiques par des semelles connectees. Les capacites mnesiques seront evaluees apres chaque position sous forme de rappel indice de chaque oeuvre observee. Un questionnaire de ressenti sera propose a la fin de l’experimentation afin d’apprecier le confort des participants. Results attendus–discussion L’observation d’un tableau en position assise, reduisant les ressources du controle postural, devrait entrainer de meilleures performances dans la tâche mnesique chez les participants (Albinet et al., 2006). Par la suite, en mettant en relation les perfomances sensorielles, motrices et cognitives, nous devrions pouvoir proposer des pistes de reflexion pour un amenagement favorable a l’optimisation posturale et mnesique d’une visite museale pour la personne âgee.

The parahippocampal cortex (PHC) participates in both perception and memory. However, the way perceptual and memory processes cooperate when we navigate in our everyday life environment remains poorly understood. We studied a stroke patient presenting a brain lesion in the right PHC, which resulted in a mild and quantifiable topographic agnosia, and allowed us to investigate the role of this structure in overt place recognition. Photographs of personally familiar and unfamiliar places were displayed during functional magnetic resonance imaging (fMRI). Familiar places were either recognized or unrecognized by the patient and 6 age- and education-matched controls in a visual post-scan recognition test. In fMRI, recognized places were associated with a network comprising the fusiform gyrus in the intact side, but also the right anterior PHC, which included the lesion site. Moreover, this right PHC showed increased connectivity with the left homologous PHC in the intact hemisphere. By contrasting recognized with unrecognized familiar places, we replicate the finding of the joint involvement of the retrosplenial cortex, occipito-temporal areas, and posterior parietal cortex in place recognition. This study shows that the ability for left and right anterior PHC to communicate despite the neurological damage conditioned place recognition success in this patient. It further highlights a hemispheric asymmetry in this process, by showing the fundamental role of the right PHC in topographic agnosia., Graphical abstract, Highlights • We studied a right occipito-temporal stroke patient using functional MRI. • This patient showed only mild signs of topographic agnosia for familiar places. • The right anterior parahippocampal cortex was recruited when places were recognized. • It showed increased connectivity with the left homotopic region during recognition.

Spatial neglect has been related to both cortical (predominantly at the temporal-parietal junction) and subcortical (predominantly of the superior longitudinal fasciculus) lesions. The objectives of this observational study were to specify the anatomical relationships of behavioral neglect in activities of daily living (N-ADLs), and the anatomical and psychometric relationships of N-ADLs on one hand and components of neglect (peripersonal neglect and personal neglect) and anosognosia on the other. Forty five patients were analyzed for behavioral difficulties in daily living (on the Catherine Bergego scale) and the main components of neglect (using conventional clinical assessments) during the first months post right hemisphere stroke. Voxel-based lesion-symptom mapping was used to identify brain areas within which lesions explained the severity of bias in each assessment (non-parametric permutation test; p

Objective Recent studies suggest that motivational cues such as rewards may be a powerful determinant of attentional selection, both in healthy subjects and in brain-damaged patients suffering from neglect. However, the exact brain mechanisms underlying these effects and their relation to other well-known attentional systems are still poorly known. Methods We designed a visual search paradigm to examine how value-based attentional priority could modulate spatial orienting in patients with pathological biases due to neglect after right hemispheric stroke. Targets were preceded by exogenous valid or invalid spatial cues, in the presence or absence of distractors that were associated with high reward values subsequent to an initial reinforcement training phase. Results We found that the learned reward value of distractors interfered with spatial reorienting toward the left (neglected) side when neglect patients were invalidly cued to the right side. Moreover, the presence of reward-associated distractors in the contralesional field interfered most with the detection of task-relevant targets on the same side, and this interference was exaggerated with more severe neglect. Voxelwise anatomical lesion analysis indicated that damage to the right angular gyrus, as well as lateral occipital and inferior temporal areas of the right hemisphere, were associated with stronger value-driven attentional effects. Conclusions Visual stimuli previously associated with rewards receive higher attentional priority during visual search despite pathological spatial biases due to neglect, and thus interfere with orienting to contralesional targets, presumably by competing with top-down mechanisms controlling exogenous spatial attention. Reward signals may bias neural activity evoked by visual stimuli, independent of conscious control, through a common priority map integrating several different attentional influences. These results do not only provide novel insights to link spatial orienting and motivational signals within current models of attention, but also open new perspectives that may usefully be exploited for neurological rehabilitation strategies in patients suffering from attentional deficits and neglect.

Sir, We would like to make a few comments on the interesting paper recently published in Brain by Karnath et al. (2011). We were impressed by the careful assessment of spatial neglect during acute and chronic phase, which was combined with a solid voxel-wise lesion symptom mapping technique in a series of 54 patients with right-hemisphere stroke. Anatomical data indicated that lesions in the superior and middle temporal gyri, the basal ganglia, as well as the inferior occipitofrontal fasciculus are responsible for spatial neglect in both acute and chronic phases. We also had the opportunity to evaluate 69 patients with right brain lesions longitudinally. Our patients were admitted after a first right-hemisphere stroke (mean delay: 7.5 ± 14.6 days), at a mean age of 64.95 ± 14.6 years. Mean delay between the acute and chronic phase was 350.21 ± 184.7 days. These demographic data are comparable with the patients of Karnath et al . (2011). Neglect was considered as present when patients failed at least two out of eight tests (Table 1)—unlike diagnoses based on two out three tests in Karnath et al . (2011). In the acute phase, 31 patients had neglect (45%). In the chronic phase, 17 of these 31 neglect patients still showed a significant impairment (55%). Using the same voxel-wise lesion mapping as Karnath et al . (2011), we found partly different results, particularly in the acute phase (detailed below). However, we believe that major differences in the findings may depend on the clinical measures used to define neglect, since this syndrome may include heterogeneous symptoms. View this table: Table 1 Neuropsychological results on paper and pencil tests. All scores were calculated as described in Verdon et al . (2010) Bowen et al . (1999) reported that the frequency of occurrence of neglect in patients with right brain damage may vary considerably and …

Spatial neglect is a complex neuropsychological disorder, in which patients fail to detect and respond to contralesional stimuli. Recent studies suggest that these symptoms may reflect a combination of different component deficits, associated with different lesion substrates. Thus, damage to right lateral prefrontal and inferior parietal regions produce different degrees of left neglect on cancellation and line bisection tasks, respectively. Here we tested for dissociable behaviors across two tasks designed to assess distinct cognitive processes possibly mediating such components, in 14 patients with right focal lesion in either the frontal or parietal lobe. In the “distractor filtering” task, patients had to respond to a visual target presented centrally, with or without a lateralized distractor. Only frontal-lesioned patients showed a marked slowing of reaction times when a central target appeared with a simultaneous right distractor (compared to center and left distractor). In the “spatial coding” task, patients had to detect a target among successive visual stimuli presented horizontally with three sequence conditions (regular/predictive or irregular/non-predictive). Only parietal-lesioned patients were unable to benefit from the predictability of the target position, with similar reaction times across all sequence conditions. By contrast, frontal patients showed faster reaction times on trials with a regular succession of stimuli (compared to random order). Taken together, these results suggest that frontal damage may contribute to left inattention by disrupting top-down control and resistance to distractors on the ipsilesional side, whereas parietal damage may disrupt the maintenance of stable locations in space across gaze shifts or time. This further supports the notion that left neglect may arise as a combined breakdown or impaired connectivity between frontal and parietal mechanisms involved (respectively) in the selective control and memory storage components of spatial attention.

Introduction/Background Unilateral spatial neglect (USN) is a neuropsychological syndrome in which patients fail to pay attention to and represent the contralesional part of the space. Standard assessment of USN is carried out with paper-and-pencil tests, which do not capture the full range of deficits (i.e., not sensitive enough; no evaluation of “far” space) or detect compensatory learning effects in chronic patients. Here we explore interactive and ecological assessments within immersive virtual reality (IVR) to overcome these limitations. Material and method Twelve chronic stroke patients (58 ± 9.4 years; 5 female; time from stroke: 15.8 ± 7.7 months) completed a battery of paper-and-pencil neuropsychological tests (line bisection, cancellation, reading, drawing, functional scales) and a IVR-based assessment for extra-personal USN. In the IVR tasks, participants were presented with a virtual environment representing a forest, via head-mounted display ( Fig. 1 ). The tasks consisted of finding static objects (level 1) or moving rabbits (levels 2–4) in the scene. Difficulty was modulated with the presence of distractors and an additional auditory dual task. Participants used the embedded head tracker in the HMD to control a pointer to select the targets in the scene, and the space bar of the computer to validate the selected item. Results Four patients presented USN in both paper-and-pencil and IVR tasks. Interestingly, two other participants showed signs of neglect in the IVR assessment without being classified as neglect patients in the paper-and-pencil tests. These patients did not show signs of USN in the items of the Catherine Bergego Scale that assesses their ability to explore the extra-personal space. Conclusion This preliminary data suggests that IVR-based assessments represent an easy-to-use and consistent tool to investigate USN, can extend its evaluation to the far space, and can detect USN in chronic patients who do not show sign of neglect in standard assessments.

Introduction Plusieurs etudes suggerent que les interventions multimodales, combinant la remediation cognitive, l’entrainement cognitif et l’exercice physique, peuvent avoir un impact positif sur les performances cognitives et le bien-etre. Toutefois, ces interventions, souvent peu ecologiques, peuvent engendrer un stress important. Le present projet vise a documenter l’effet physiologique et neurocognitif d’une visite au musee aupres de personnes en sante. Materiel et methode Cette etude vise a recruter six participants adultes. Ils auront a remplir des questionnaires (Visual analog stress, ASTA, Warwick-Edinburgh Mental Well-being Scale, EQ-5D) et devront completer une breve batterie neuropsychologique, avant et apres la visite museale. Cette visite sera realisee avec un systeme d’imagerie cerebrale portable qui permettra de mesurer l’activite cerebrale sur la majeure partie du cortex. Resultats attendus Une diminution significative des performances aux echelles de mesures du stress et de l’etat anxieux sont attendues ainsi qu’une augmentation significative du score a l’echelle de mesure du bien-etre et ce, entre le debut et la fin de la visite du musee. De plus, il est attendu d’observer une augmentation de l’activite corticale (cortex prefrontal) correlee a la diminution de l’etat de stress entre le debut et la fin de la visite. Discussion Ce projet permettra de fournir des informations utiles pour proposer une intervention accessible et ecologique visant a diminuer l’etat anxieux et le stress tout en favorisant une augmentation de la perception de bien-etre pour les patients et pour la population en general. Projet MOB-MBAM : Caracteriser l’interaction environnement–personne lors d’une visite museale : une etude de faisabilite de collectes de donnees multiples et ponctuelles de la mobilite dans l’espace public. Volet 2 : les 6 sous-projets.

Our perception of space is based on the integration of signals from vestibular, visual, and somatosensory systems. These sensory modalities allow awareness of the displacements and positions of our body and body parts, as well as the locations of objects in extra-personal space. Brain lesions can produce severe deficits in the representation of personal or extra-personal space, as demonstrated by the syndrome of unilateral (left) spatial neglect after (right) hemisphere stroke. Many aspects of the neglect syndrome have been ascribed to pathological biases in the internal representation of space, some of which can also be observed in patients with dysfunction of the vestibular pathways, either in the peripheral or central nervous system. The recent studies showed for example, neglect patients like vestibular patients exhibit an ipsilesional (e.g. rightward) deviation of their subjective body midline when pointing straight-ahead, as well as ipsilesional biases in posture and abnormal perception of verticality. Therefore, it has been hypothesized that some impairment in the integration of vestibular signals at the brain level might contribute to impaired spatial cognition and neglect after focal hemispheric damage. A critical role for the vestibular system in neglect would be consistent with its central projections on multisensory integration areas in parietal and frontal cortex which are thought to be involved in the representation of space across egocentric and allocentric spatial frames of reference, and which are typically damaged in neglect patients.

Introduction L’evaluation en milieu reel ou ecologique momentanee (EMEM) permet d’obtenir des informations uniques et differentes de l’evaluation traditionnelle en milieu clinique ou en laboratoire. Les musees sont des environnements riches pour la comprehension du comportement humain. Leurs vastes espaces requierent de bonnes capacites de mobilite et de navigation pour une participation experientielle optimale. Notre projet vise a caracteriser la mobilite dans un environnement ecologique, le musee des Beaux-Arts de Montreal (MBAM), en mettant en commun des donnees multiples sur la posture, l’equilibre et la locomotion et les facteurs qui les influencent, comme la cognition. Materiel et methode Ce projet consiste a explorer la faisabilite de collecter des donnees issues de plusieurs sous-projets de recherche, lors d’une journee de visite reguliere du MBAM. Cent soixante-neuf membres VIP du musee seront recrutes. Ils seront aleatoirement attribues a un des sous-projets tenus simultanement. Des mesures de faisabilite seront recoltees a l’aide d’observations, de questionnaires et d’entrevues semi-structurees aupres des chercheurs, participants et employes du musee. L’agregation de ces donnees multiples et leur analyse permettra de juger de la faisabilite du projet et la validite des donnees des sous-projets. Resultats attendus/Discussion Les resultats immediats de l’etude devraient fournir des recommandations specifiques conduisant a des modifications du protocole de sorte a pouvoir plus facilement tenir ce type de collectes a l’avenir. Les produits livrables a court et moyen termes comprendront des solutions concretes benefiques pour les autres jours de collectes, les autres groupes de visiteurs evalues (ex. visiteurs post-accident neurologique) et rendront a terme le MBAM et d’autres sites similaires des environnements de collectes de donnees de type EMEM concevables.

Previous research suggests that people construct mental time lines to represent and reason about time. However, is the ability to represent space truly necessary for representing events along a mental time line? Our results are the first to demonstrate that deficits in spatial representation (as a function of left hemispatial neglect) also result in deficits in representing events along the mental time line. Specifically, we show that patients with left hemispatial neglect have difficulty representing events that are associated with the past and, thus, fall to the left on the mental time line. These results demonstrate that representations of space and time share neural underpinnings and that representations of time have specific spatial properties (e.g., a left and a right side). Furthermore, it appears that intact spatial representations are necessary for at least some types of temporal representation.