Autotopagnosia

INTRODUCTION: We report a very unique clinical presentation of a patient who complained, after a left parietal brain damage, about feeling tactile stimulations on his right upper limb without being able to localize them. METHODS: Using a single case study approach, we report three experiments relying on several custom-made tasks to explore the different levels of somatosensory information processing, ranging from somato-sensation to somato-representation. RESULTS: Our results showed a preserved ability to localize tactile stimuli applied on the right upper limb when using pointing responses while the ability to localize was less efficient when having to name the stimulated part (akin Numbsense)...

Heterotopagnosia-without-Autotopagnosia (HwA) is characterized by the incapacity to point to body parts on others, but not on one's own body. This has been classically interpreted as related to a self-other distinction, with impaired visual representations of other bodies seen in third person perspective (3PP), besides spared own body somatosensory representations in 1PP. However, HwA could be impacted by a deficit in the integration of visual and somatosensory information in space, that are spatially congruent in the case of one's own body, but not for others' body...

We describe an unusual case of a 68-year-old male affected by cerebral amyloid angiopathy and cortical blindness associated with Anton's syndrome. In addition, our patient presented with autotopagnosia, a form of agnosia characterized by loss of body spatial representation. Neuropsychological assessment evidenced cognitive impairment. Magnetic Resonance Imaging showed hemorrhagic foci in the left occipital and right occipito-parietal lobe, paratrigonal white matter, and post-ischemic parenchymal gliosis. The pattern-reversal of visual evoked potentials were indicative bilateral visual pathway of integrity of the...

This paper discusses the laterality of parietal association areas, focusing on hemispatial neglect and body representation. Extra-personal spatial neglect can be severe and is frequently observed following right parietal lesions; personal neglect is also common with right parietal lesions. According to the frame of awareness and perception, I speculate that the awareness of space is related to hemispatial neglect of extra-personal space, and awareness of body is related to personal neglect. Both clinical symptoms are common with right parietal lesions...

RATIONALE: Reversible splenial lesion syndrome (RESLES) is a reversible condition with an excellent prognosis in most patients. The clinical features include altered states of consciousness, delirium, headache, and seizures, but no callosal disconnection syndromes have been described in RESLES. PATIENT CONCERNS: We presented a 57-year-old patient with alien hand syndrome, autotopagnosia, gait disorders, and left ideomotor apraxia after blood transfusion. The brain magnetic resonance imaging (MRI) showed a few regions with high signal intensity in the genu, body, and splenium of the right corpus callosum on diffusion weighted images...

A 69-year-old male (N.A.) with Creutzfeldt-Jakob disease showed pure autotopagnosia. We administered tests evaluating his ability to name his own body parts, to point to body parts (his own and examiner's), and to recognize positional relationships between his body parts by verbal questions and responses. We found impaired localization of the patient's own body parts by pointing and impaired recognition of positional relationships between his body parts. However, there was no impairment in naming his own body parts or in localizing the examiner's body parts...

Some unusual neuropsychological syndromes are rarely reported in the neuropsychological literature. This paper presents a review of four of these unusual clinical syndromes: (1) somatoparaphrenia (delusional belief in which a patient states that the limb contralateral to a brain pathology, does not belong to him/her); (2) akinetopsia (cortical syndrome in which patient losses the ability to perceive visual motion); (3) reduplicative paramnesia (believe that a familiar place, person, object, or body part has been duplicated); and (4) autotopagnosia (disturbance of body schema involving the loss of ability to localize, recognize, or identify the specific parts of one's body)...

Knowledge of the spatial layout of bodies is mediated by a representation called the body structural description, damage to which results in the condition of autotopagnosia in which patients are impaired in judgments about the location and configuration of body parts. While a large literature has investigated disruption of the body structural description, little research has examined its accuracy in healthy individuals. I show that people have systematically distorted knowledge of the configuration of hands...

A variety of disorders have been associated with the concept of body schema. However, this concept has been interpreted in many ways, and there is no consensus on the nature and cognitive mechanisms of body schema. Historically, two major issues have been discussed. One was the body-specificity of the body schema, and the other was the relationship between input and output modality. Autotopagnosia, an inability to localize and orient different parts of the body, has been a focus of attention because it is thought to provide insight into the function of body schema...

A historical review of calculation abilities is presented. Counting, starting with finger sequencing, has been observed in different ancient and contemporary cultures, whereas number representation and arithmetic abilities are found only during the last 5000-6000 years. The rationale for selecting a base of ten in most numerical systems and the clinical association between acalculia and finger agnosia are analyzed. Finger agnosia (as a restricted form of autotopagnosia), right-left discrimination disturbances, semantic aphasia, and acalculia are proposed to comprise a single neuropsychological syndrome associated with left angular gyrus damage...

We report a patient with autotopagnosia (JD) who was unable to code the position of body parts relative to each other and who failed to update the position of body parts after passive movements. JD's performance in Studies 1-4 suggest that her ability to code the dynamic location of body parts with respect to each other ("intrinsic egocentric" spatial coding) was impaired, and that she employed a compensatory strategy by means of which the location of body parts was computed with respect to objects in the environment ("extrinsic egocentric" spatial coding)...

Previous accounts of autotopagnosia (e.g., Ogden, 1985; Pick, 1908; Semenza, 1988) propose that the disorder is attributable to deficits in "mental images," visual body schema, or semantic representations. A recent account (Sirigu, Grafman, Bressler, & Sunderland, 1991b) posits deficits in visual structural descriptions of the human body and its parts, in the context of spared semantic and proprioceptivespatio-motor body representations, but provides no evidence bearing on the nature or format of the putatively damaged representation...

No abstract text is available yet for this article.

Neuropsychological studies suggest that patients with left parietal lesions may show impaired localization of parts of either their own or the examiner's body, despite preserved ability to identify isolated body parts. This deficit, called autotopagnosia, may result from damage to the Body Structural Description (BSD), a representation which codes spatial relationships among body parts. We used functional magnetic resonance imaging to identify the neural mechanisms underlying the BSD. Two human body or building parts (factor: STIMULI) were shown to participants who either identified them or evaluated their distance (factor: TASK)...

The psychic tonus model (Braun and colleagues, 1999, 2002, 2003, 2006) states that the left hemisphere is a "booster" of internal experience and behavior in general, and that the right hemisphere is a "dampener". Twenty-five patients with a "positive" extreme disturbance of body schema (somatoparaphrenia) and 37 patients with a "negative" disturbance of body schema (autotopagnosia or Gerstmann's syndrome), all following a unilateral parietal lesion, were found in the literature and were analyzed to test predictions from Braun's "psychic tonus" model...

A left hemisphere stroke patient presented a disproportionate difficulty for body parts knowledge without autotopagnosia. The deficit concerned the lexical-semantic representation of body parts and was most severe for limbs. The ability to gesture was spared and action naming was not more impaired than object naming. On the basis of normal naming latencies, we conclude that limbs are the most vulnerable component of the overall category of body parts. This vulnerability is not explained by unbalanced nuisance variables...

The authors summarize the data of 60 patients of the Memory Clinic of the National Institute of Psychiatry and Neurology between 6 January 1992 and 6 June 1994 where the probable Alzheimer's disease (NINCDS-ADRDA) was diagnosed. It was examined whether it was possible to isolate homogenous subtypes based on clinical data. Interesting differences of tendency level could be demonstrated in the groups formed on the basis of data published in the literature. Differences of statistical significance level were as follows: occurrence of depression in the groups created on the basis of the patient age at the time of onset of the disease (early-late onset), and of alexia and autotopagnosia in the groups created on the basis of progression rate (slow - quick)...

No abstract text is available yet for this article.

Since Pick's seminal studies on autotopagnosia dating back to the beginning of last century, no agreement has been reached regarding the nature of the putative representations underlying the act of pointing to body parts. One influential account proposed the existence of a meta-representation, eventually organised as a module, specifically engaged in encoding spatial relationships of bodies. This body-specific representational level has been supposed to be equally involved in processing other persons' bodies as well as one's own...

We report a case of pure autotopagnosia (AT) following a left subcortical vascular accident. The absence of any language disorder, general mental deterioration or other cognitive impairments in this patient allowed an in-depth study of AT. Several tests of body representation and object and animal representation, as well as tests assessing semantic skills were administered to verify current interpretations of AT. Results showed a clear-cut dissociation between defective performances in body representation tests and normal performances on tests involving other kinds of stimuli...