Antonella Di Vita

To move or not to move, that is the question! Body schema and non-action oriented body representations: An fMRI meta-analytic study.

Many studies have attempted to identify the different cognitive components of body representation (BR). Due to methodological issues, the data reported in these studies are often confusing. Here we summarize the fMRI data from previous studies and explore the possibility of a neural segregation between BR supporting actions (body-schema, BS) or not (non-oriented-to-action-body-representation, NA). We performed a general activation likelihood estimation meta-analysis of 59 fMRI experiments and two individual meta-analyses to identify the neural substrates of different BR. Body processing involves a wide network of areas in occipital, parietal, frontal and temporal lobes. NA selectively activates the somatosensory primary cortex and the supramarginal gyrus. BS involves the primary motor area and the right extrastriate body area. Our data suggest that motor information and recognition of body parts are fundamental to build BS. Instead, sensory information and processing of the egocentric perspective are more important for NA. In conclusion, our results strongly support the idea that different and segregated neural substrates are involved in body representations orient or not to actions.

The brain network for self-feeling: A symptom-lesion mapping study

Ongoing signals from ones own body (interoception) allow experience of self-feeling. In early studies interoception strictly referred to the awareness of visceral sensation but recent theories have expanded this concept to denote the ongoing status of the body. Here we asked left and right focal brain-damaged patients to answer questions about their interoceptive feelings, and correlated their responses to a quantitative measure of their lesions (voxel-based symptom-lesion mapping). By these means we could reveal that three key structures contribute to building up the feeling of self, namely insula (interoceptive modulator), amygdala (emotional modulator) and putamen (motor modulator). This brain network may be necessary for the integrity of self-feeling. A dysfunction of this network might impair perception of the inner body state, and also account for psychological disturbances, such as the somatic symptom disorders, in which individuals experience subjective symptoms suggesting physical illness or injury despite medical test results which are normal, and clinical examination do not disclose relevant medical conditions.

Body representation alterations in personal but not in extrapersonal neglect patients

ABSTRACT There is still a matter of debate around the nature of personal neglect. Is it an attention disorder or a body representation disorder? Here we investigate the presence of body representation deficits (i.e., the visuo-spatial body map) in right and left brain-damaged patients and in particular in those affected by personal neglect. 23 unilateral brain-damaged patients (5 left-brain-damaged and 18 right-brain-damaged patients) and 15 healthy controls took part in the study. The visuo-spatial body map was assessed by means of the “Frontal body-evocation subtest (FBE),” in which participants have to put tiles representing body parts on a small wooden board where only the head is depicted as a reference point. In order to compare performance on the FBE with performance on an inanimate object that had well-defined right and left sides, participants also performed the “Car test.” Group statistical analysis shows that the performance of patients with personal neglect is significantly worse than that of the controls and patients without personal neglect in the FBE but not in the Car test. Single case analyses of the five patients with pure personal neglect confirm the results of group analysis. Our data supports the hypothesis that personal neglect is a pervasive body representation disorder.

The way to “left” Piazza del Popolo: damage to white matter tracts in representational neglect for places

The ability of seeing with the mind’s eye, the visual mental imagery, is peculiarly compromised in patients with representational neglect. Representational neglect affects the processing of the left side of a mental image and may selectively concern the ability to imagine places and/or objects. Right-brain damaged patients with representational neglect for places (RN+) lose the ability to imagine themselves within a familiar place and fail in transforming an egocentric representation of the environment into an allocentric one and vice-versa. A peak region located at the posterior junction between the parietal and temporal lobes has emerged as pivotal in determining representational neglect for places. Here we aimed at verifying whether white matter disconnections affecting parietal lobe, by preventing the integration of egocentric information with the allocentric one, play a role in representational neglect for places. A track-wise statistical analysis on 58 right brain damaged patients, with and without extrapersonal perceptual neglect and/or representational neglect for places, suggests that the disconnection of the superior longitudinal fasciculus and that of the posterior arcuate segment, together with the disconnection of a fronto-parietal u-shaped tract, may be crucial in determining the representational neglect for places. These results suggest that representational neglect for places emerges from a complex pattern of lesion location and disconnection that involves parietal, temporal and frontal lobes.

Neural substrates of Internally-Based and Externally-Cued Timing: an activation likelihood estimation (ALE) meta-analysis of fMRI studies

HighlightsInterval timing involves both internally‐based and externally‐cued timing processes.ALE meta‐analysis suggests these processes might be partially dissociated.Internally‐based timing involves areas also involved in externally‐cued timing.SMA, right IFG, left PCG and INS are more activated during externally‐cued timing. &NA; A dynamic interplay exists between Internally‐Based (IBT) and Externally‐Cued (ECT) time processing. While IBT processes support the self‐generation of context‐independent temporal representations, ECT mechanisms allow constructing temporal representations primarily derived from the structure of the sensory environment. We performed an activation likelihood estimation (ALE) meta‐analysis on 177 fMRI experiments, from 79 articles, to identify brain areas involved in timing; two individual ALEs tested the hypothesis of a neural segregation between IBT and ECT. The general ALE highlighted a network involving supplementary motor area (SMA), intraparietal sulcus, inferior frontal gyrus (IFG), insula (INS) and basal ganglia. We found evidence of a partial dissociation between IBT and ECT. IBT relies on a subset of areas also involved in ECT, however ECT tasks activate SMA, right IFG, left precentral gyrus and INS in a significantly stronger way. Present results suggest that ECT involves the detection of environmental temporal regularities and their integration with the output of the IBT processing, to generate a representation of time which reflects the temporal metric of the environment.

Selective map-following navigation deficit: A new case of developmental topographical disorientation

ABSTRACT Introduction: Developmental topographical disorientation (DTD) is a lifelong condition in which affected individuals are selectively impaired in navigating space. Although it seems that DTD is widespread in the population, only a few cases have been studied from both a behavioral and a neuroimaging point of view. Here, we report a new case of DTD, never described previously, of a young woman (C.F.) showing a specific deficit in translating allocentrically coded information into egocentrically guided navigation, in presence of spared ability of constructing such representations. Method: A series of behavioral experiments was performed together with a resting-state functional magnetic resonance imaging (fMRI). Results: We demonstrated that C.F. was fully effective in learning and following routes and in building up cognitive maps as well as in recognizing landmarks. C.F.’s navigational skills, instead, dropped drastically in the map-following task when she was required to use a map to navigate in a novel environment. The rs-fMRI experiment demonstrated aberrant functional connectivity between regions within the default-mode network (DMN), and in particular between medial prefrontal cortex and posterior cingulate, medial parietal, and temporal cortices. Discussion: Our results would suggest that, at least in C.F., dysfunctional coactivation of core DMN regions would interfere with the ability to exploit cognitive maps for real-life navigation even when these maps can be correctly built.

Action and Non-Action Oriented Body Representations: Insight from Behavioural and Grey Matter Modifications in Individuals with Lower Limb Amputation

Objective Following current model of body representations, we aimed to systematically investigate the association between brain modifications, in terms of grey matter loss, and body representation deficits, in terms of alterations of the body schema (BS) and of non-action oriented body representations (NA), in individuals with lower limb amputation (LLA). Method BS and NA (both semantic and visuospatial NA) were evaluated in 11 healthy controls and in 14 LLA, considering the impact of clinical variables such as prosthesis use. The association between BS and NA deficits and grey matter loss was also explored in LLA by using Voxel Based Morphometry analysis. Results LLAs performance was fine in terms of semantic NA, while it showed behavioural impairments both in BS and visuospatial NA as compared to healthy controls. Interestingly the visuospatial NA performance was related to the amount of prosthesis use. NA deficits in terms of visuospatial body map processing were associated with grey matter reduction in left (lobule VIII) and right (crus II) cerebellum, while BS deficits were associated with grey matter reduction in right anterior cingulate cortex and the bilateral cuneus. No significant association was detected for semantic NA. Conclusion The study of BS and NA representations after limb loss has informed our understanding of the different dynamics (i.e., adjustments to body change) of such representations, supporting current cognitive models of body representation. The clinical relevance of present findings is also discussed.

Neuropsychology as a profession in Italy

Abstract The purpose of this study was to analyze the characteristics of individuals working in the field of neuropsychology in Italy, as part of a larger study examining the practice of neuropsychology across various countries. They were asked about their background, professional training, current work situation, types of assessment, preferred diagnostic procedures, as well as the rehabilitation techniques, their targeted populations, teaching responsibilities, and research activities. A total of 154 professionals completed an online survey from April 28, 2016 through June 30, 2016. The majority of participants were women, with a mean age of 42.6 years. Participants reported working for the National Health System, in private practice, or in private rehabilitation facilities. Overall, they reported being very satisfied with their work. Those who identified themselves as neuropsychologists primarily assessed individuals with dementia, stroke, movement disorders, and traumatic brain injury. While the majority of participants declared no problems with the instruments they used, others reported complaints, including but not limited to the financial cost of current neuropsychological tests and the lack of psychometric support. The main perceived obstacles were the lack of willingness to collaborate among professionals, the scarcity of academic training programs, and the lack of clinical training opportunities.