scholarly journals The strange role of brain lesion size in cognitive neuropsychology

Cortex ◽  
2021 ◽  
Author(s):  
Christoph Sperber
Keyword(s):  
Brain Lesion ◽  
Lesion Size ◽  
Cognitive Neuropsychology

scholarly journals The strange role of brain lesion size in cognitive neuropsychology

2021 ◽  
Author(s):  
Christoph Sperber
Keyword(s):  
Cognitive Deficits ◽  
Outcome Prediction ◽  
Causal Relation ◽  
Size Control ◽  
Lesion Size ◽  
List Type ◽  
Cognitive Neuropsychology ◽  
Lesion Location ◽  
Post Stroke

Abstract The size of brain lesions is a variable that is frequently considered in cognitive neuropsychology. In particular, lesion-deficit inference studies often control for lesion size, and the association of lesion size with post-stroke cognitive deficits and its predictive value are studied. In the present article, the role of lesion size in cognitive deficits and its computational or design-wise consideration is discussed and questioned. First, I argue that the commonly discussed role or effect of lesion size in cognitive deficits eludes us. A generally valid understanding of the causal relation of lesion size, lesion location, and cognitive deficits is unachievable. Second, founded on the theory of covariate control, I argue that lesion size control is no valid covariate control. Instead, it is identified as a procedure with only situational benefits, which is supported by empirical data. This theoretical background is used to suggest possible research practices in lesion-deficit inference, post-stroke outcome prediction, and behavioural studies. Last, control for lesion size is put into a bigger methodological and also historical context – it is identified to relate to a long-known association problem in neuropsychology, which was previously discussed from the perspectives of a mislocalisation in lesion-deficit mapping and the symptom complex approach. Highlights - Lesion size is a factor that is often considered or controlled in neuropsychology - No general causal relation between lesion size, lesion location and deficit exists - Lesion size in brain mapping, outcome prediction and behavioural study is discussed - Lesion size control is no valid covariate control - Practical suggestions and guidelines how to consider lesion size are provided

scholarly journals The Role of White Matter Disconnection in the Symptoms Relating to the Anarchic Hand Syndrome: A Single Case Study

2021 ◽  
Vol 11 (5) ◽  
pp. 632
Author(s):  
Valentina Pacella ◽  
Giuseppe Kenneth Ricciardi ◽  
Silvia Bonadiman ◽  
Elisabetta Verzini ◽  
Federica Faraoni ◽  
...  
Keyword(s):  
White Matter ◽  
Single Case ◽  
Brain Lesion ◽  
Structural Connectivity ◽  
Disconnection Syndrome ◽  
Neuroimaging Data ◽  
Neuropsychological Investigation ◽  
Anterior Posterior

The anarchic hand syndrome refers to an inability to control the movements of one’s own hand, which acts as if it has a will of its own. The symptoms may differ depending on whether the brain lesion is anterior, posterior, callosal or subcortical, but the relative classifications are not conclusive. This study investigates the role of white matter disconnections in a patient whose symptoms are inconsistent with the mapping of the lesion site. A repeated neuropsychological investigation was associated with a review of the literature on the topic to identify the frequency of various different symptoms relating to this syndrome. Furthermore, an analysis of the neuroimaging regarding structural connectivity allowed us to investigate the grey matter lesions and white matter disconnections. The results indicated that some of the patient’s symptoms were associated with structures that, although not directly damaged, were dysfunctional due to a disconnection in their networks. This suggests that the anarchic hand may be considered as a disconnection syndrome involving the integration of multiple antero-posterior, insular and interhemispheric networks. In order to comprehend this rare syndrome better, the clinical and neuroimaging data need to be integrated with the clinical reports available in the literature on this topic.

scholarly journals The Role of White Matter Disconnection in the Symptoms Relating to the Anarchic Hand Syndrome: A Single Case Study

2021 ◽  
Author(s):  
Valentina Pacella ◽  
Giuseppe Kenneth Ricciardi ◽  
Silvia Bonadiman ◽  
Elisabetta Verzini ◽  
Federica Faraoni ◽  
...  
Keyword(s):  
White Matter ◽  
Single Case ◽  
Brain Lesion ◽  
Structural Connectivity ◽  
Disconnection Syndrome ◽  
Neuroimaging Data ◽  
Neuropsychological Investigation ◽  
Anterior Posterior

The anarchic hand syndrome refers to an inability to control the movements of one’s own hand which acts as if it had a will of its own. The symptoms may differ depending on whether the brain lesion is anterior, posterior, callosal or subcortical, but the relative classifications are not conclusive. This study investigates the role of white matter disconnections in a patient whose symptoms are inconsistent with the mapping of the lesion site. A repeated neuropsychological investigation was associated with a review of the literature on the topic to identify the frequency of various different symptoms relating to this syndrome. Furthermore, an analysis of the neuroimaging regarding structural connectivity allowed us to investigate the grey matter lesions and white matter disconnections. The results indicated that some of the patient’s symptoms were associated with structures that, although not directly damaged, were dysfunctional due to a disconnection in their networks. This suggests that the anarchic hand may be considered as a disconnection syndrome involving the integration of multiple antero-posterior, insular and interhemispheric networks. In order to comprehend this rare syndrome better, the clinical and neuroimaging data need to be integrated with the clinical reports available in the literature on the topic.

CIN 3: the role of lesion size in invasion

1992 ◽  
Vol 99 (7) ◽  
pp. 583-586 ◽  
Author(s):  
PENELOPE TIDBURY ◽  
ALBERT SINGER ◽  
DAVID JENKINS
Keyword(s):  
Lesion Size

Contralesional plasticity following constraint-induced movement therapy benefits outcome: contributions of the intact hemisphere to functional recovery

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Abigail L. Kerr
Keyword(s):  
Functional Recovery ◽  
Daily Living ◽  
Animal Studies ◽  
Movement Therapy ◽  
Lesion Size ◽  
Neural Mechanisms ◽  
Constraint Induced Movement Therapy ◽  
Current Review ◽  
Paretic Limb

Abstract Stroke is a leading cause of death and disability worldwide. A common, chronic deficit after stroke is upper limb impairment, which can be exacerbated by compensatory use of the nonparetic limb. Resulting in learned nonuse of the paretic limb, compensatory reliance on the nonparetic limb can be discouraged with constraint-induced movement therapy (CIMT). CIMT is a rehabilitative strategy that may promote functional recovery of the paretic limb in both acute and chronic stroke patients through intensive practice of the paretic limb combined with binding, or otherwise preventing activation of, the nonparetic limb during daily living exercises. The neural mechanisms that support CIMT have been described in the lesioned hemisphere, but there is a less thorough understanding of the contralesional changes that support improved functional outcome following CIMT. Using both human and non-human animal studies, the current review explores the role of the contralesional hemisphere in functional recovery of stroke as it relates to CIMT. Current findings point to a need for a better understanding of the functional significance of contralesional changes, which may be determined by lesion size, location, and severity as well stroke chronicity.

Brain Tumors

2016 ◽  
pp. 11-24 ◽  
Author(s):  
Chikezie Eseonu ◽  
Jordina Rincon-Torroella ◽  
Alfredo Quiñones-Hinojosa
Keyword(s):  
Brain Tumor ◽  
Brain Tumors ◽  
Demyelinating Disease ◽  
Brain Lesion ◽  
Pituitary Tumors ◽  
Current Treatment ◽  
Preoperative Care ◽  
Adult Brain ◽  
Surgical Approaches

Brain tumor cases make up a significant part of the neurosurgery Oral Board Exam. A multitude of brain tumors exist and can be intraaxial or extraaxial. When considering a differential diagnosis for a brain lesion, infection, hematomas, infarctions, thrombosed aneurysms, inflammation, and demyelinating disease must be considered in addition to tumors. Common adult brain tumors consist of gliomas, meningiomas, metastases, and pituitary tumors. Management of brain tumors consists of understanding preoperative care, indications for surgery, surgical approaches, interpretation of preoperative and postoperative imaging, intraoperative and postoperative complications, and the role of adjuvant therapy, including chemotherapy and radiotherapy. Reviewing these essential points for the most common brain tumor cases and mastering the current treatment recommendations for common tumors will also be helpful for the boards.

scholarly journals Neuroprotective role of lactate in rat neonatal hypoxia-ischemia

2020 ◽  
pp. 0271678X2090835 ◽  
Author(s):  
Hélène Roumes ◽  
Ursule Dumont ◽  
Stéphane Sanchez ◽  
Leslie Mazuel ◽  
Jordy Blanc ◽  
...  
Keyword(s):  
Neuroprotective Effect ◽  
Waste Product ◽  
Brain Lesion ◽  
Complete Recovery ◽  
Long Term Memory ◽  
Lesion Volume ◽  
Apparent Diffusion Coefficients ◽  
Hypoxia Ischemia

Hypoxic-ischemic (HI) encephalopathy remains a major cause of perinatal mortality and chronic disability in newborns worldwide (1–6 for 1000 births). The only current clinical treatment is hypothermia, which is efficient for less than 60% of babies. Mainly considered as a waste product in the past, lactate, in addition to glucose, is increasingly admitted as a supplementary fuel for neurons and, more recently, as a signaling molecule in the brain. Our aim was to investigate the neuroprotective effect of lactate in a neonatal (seven day old) rat model of hypoxia-ischemia. Pups received intra-peritoneal injection(s) of lactate (40 μmol). Size and apparent diffusion coefficients of brain lesions were assessed by magnetic resonance diffusion-weighted imaging. Oxiblot analyses and long-term behavioral studies were also conducted. A single lactate injection induced a 30% reduction in brain lesion volume, indicating a rapid and efficient neuroprotective effect. When oxamate, a lactate dehydrogenase inhibitor, was co-injected with lactate, the neuroprotection was completely abolished, highlighting the role of lactate metabolism in this protection. After three lactate injections (one per day), pups presented the smallest brain lesion volume and a complete recovery of neurological reflexes, sensorimotor capacities and long-term memory, demonstrating that lactate administration is a promising therapy for neonatal HI insult.

scholarly journals Neuroanatomic correlates of visual hallucinations in poststroke hemianopic patients

Neurology ◽  
2020 ◽  
Vol 94 (18) ◽  
pp. e1885-e1891
Author(s):  
Fiora Martinelli ◽  
Céline Perez ◽  
Florent Caetta ◽  
Michaël Obadia ◽  
Julien Savatovsky ◽  
...  
Keyword(s):  
Visual Recognition ◽  
Striate Cortex ◽  
Clinical Care ◽  
Brain Lesion ◽  
Inverse Correlation ◽  
Occipital Lobe ◽  
Lesion Size ◽  
Homonymous Hemianopia ◽  
Small Lesion ◽  
Visual Hallucinations

ObjectivesHomonymous hemianopia (HH) is the most frequent visual-field defect after a stroke. Some of these patients also have visual hallucinations, the origin and frequency of which remain largely unknown. The aims of this work were to determine the occurrence of visual hallucinations among poststroke hemianopic patients in function of the location (Brodmann areas) of the brain lesion, as determined by MRI, and to study the neuroanatomic correlates of these hallucinations by nature, frequency, and type.MethodsOne hundred sixteen patients with HH who had had a stroke in the posterior region, including the occipital lobe, participated in the study. We evaluated the frequency and nature of visual hallucinations with the Questionnaire for Hallucinations in Homonymous Hemianopia. The volume of each patient's brain lesion was modeled in 3 dimensions.ResultsOf 116 patients with an HH from a cortical infarction, 85 were excluded due to confounding factors associated with hallucinations. In the final cohort of 31 patients matched for lesion location and etiology, 58% had experienced hallucinations. A significant inverse correlation between lesion size and the frequency of visual hallucinations emerged. The presence of visual hallucinations in poststroke hemianopic patients requires a relatively small lesion that includes, at the very least, loss of the striate cortex but that spares Brodmann area 19, 20, and 37.ConclusionOur results suggest that visual hallucinations might be due to complex interactions between damaged areas and intact areas of the visual cortex. We discuss these findings regarding models of perception and of visual recognition. Our results also have implications for the clinical care of patients with HH who have had a stroke.

scholarly journals The Role of Fine Needle Aspiration of Orbital Lesions: A Case Series

2016 ◽  
Vol 60 (1) ◽  
pp. 31-38 ◽  
Author(s):  
Fabio Pagni ◽  
Marta Jaconi ◽  
Andrew James Smith ◽  
Ambrogio Brenna ◽  
Maria Gabriella Valente ◽  
...  
Keyword(s):  
Case Series ◽  
Needle Aspiration ◽  
Lesion Size ◽  
Fine Needle ◽  
Computed Tomography Scans ◽  
The Mean ◽  
The Right ◽  
First Time ◽  
Orbital Lesions

Objective: This paper analyzes a series of ultrasound (US)-guided orbital fine needle aspirations (FNAs) which provide diagnostic information that cytopathologists approaching orbital lesions for the first time can find useful and underlines the importance of teamwork. Study Design: The investigators retrospectively obtained data from 24 consecutive orbital FNAs. For all patients, a complete clinicoradiological database was created. FNAs were performed under US guidance with 25-gauge needles and an aspiration biopsy syringe gun, and sent to the Department of Pathology for examination and data management. Results: The mean age of the patients was 54 years. Imaging studies included US, magnetic resonance imaging and computed tomography scans; 9 lesions involved the right orbit and 15 the left orbit. The mean lesion size was 23.6 ± 7.2 mm. After microscopic examination, 7 smears were labeled as ‘nondiagnostic', while in 17 cases a definitive diagnosis was proposed, which always proved to be correct (70.8%, specificity = 100%). Conclusions: The investigators believe that FNA biopsy of orbital masses is a necessary step; its weaknesses lie in the particularly delicate site of sampling and the extreme heterogeneity of lesions. Nevertheless, when orbital FNA is performed within a well-coordinated multidisciplinary team, it is a powerful tool that can be used to define the most appropriate management of these patients.

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