Dissociating language switching from executive control in bilinguals with MCI.

Bilingual language control is a dynamic cognitive system that enables individuals to effectively manage language use and prevent interference when switching between languages. Research indicates that certain neurodegenerative conditions may influence language-switching abilities or hinder the suppression of cross-language interference. However, it remains uncertain whether neurodegeneration primarily affecting mesial temporal structures, such as Mild Cognitive Impairment (MCI), impacts lexical retrieval in dual-language naming conditions.

Understanding language and cognition after brain surgery - Tumour grade, fine-grained assessment tools and, most of all, individualized approach.

Cognitive performance influences the quality of life and survival of people with glioma. Thus, a detailed neuropsychological and language evaluation is essential. In this work, we tested if an analysis of errors in naming can indicate semantic and/or phonological impairments in 87 awake brain surgery patients.

The black box of global aphasia: Neuroanatomical underpinnings of remission from acute global aphasia with preserved inner language function.

Objective: We studied an unusual case of global aphasia (GA) occurring after brain tumor removal and remitting one-month after surgery. After recovering, the patient reported on her experience during the episode, which suggested a partial preservation of language abilities (such as semantic processing) and the presence of inner speech (IS) despite a failure in overt speech production. Thus, we explored the role of IS and preserved language functions in the acute phase and investigated the neuroanatomical underpinnings of this severe breakdown in language processing.

Active bilingualism delays the onset of mild cognitive impairment.

Lifelong bilingualism may contribute to cognitive reserve (CR) in neurodegenerative diseases as shown by a delay of the age at symptom onset in bilinguals with Alzheimer's disease (AD) and Mild Cognitive Impairment (MCI). However, some studies have failed to show this bilingual advantage, suggesting that it might depend on the type and degree of bilingualism. In the present study, we tested the hypothesis that active bilingualism, defined as the continuous use of the two languages as opposed to second language exposition only, may protect against cognitive decline.

Electrophysiological correlates of feedback processing in subarachnoid hemorrhage patients.

Patients with subarachnoid hemorrhage (SAH) secondary to anterior communicating artery (AComA) aneurysm rupture often experience deficits in executive functioning and decision-making. Effective decision-making is based on the subjects' ability to adjust their performance based on feedback processing, ascribing either positive or negative value to the actions performed reinforcing the most adaptive behavior in an appropriate temporal framework. A crucial brain structure associated to feedback processing is the medial prefrontal cortex (mPFC), a brain region frequently damaged after AComA aneurysm rupture.

Autobiographical memory in epileptic patients after temporal lobe resection or bitemporal hippocampal sclerosis.

The human hippocampus is believed to be a crucial node in the neural network supporting autobiographical memory retrieval. Structural mesial temporal damage associated with temporal lobe epilepsy (TLE) provides an opportunity to systematically investigate and better understand the local and distal functional consequences of mesial temporal damage in the engagement of the autobiographical memory network. We examined 19 TLE patients (49.

White-matter pathways and semantic processing: intrasurgical and lesion-symptom mapping evidence.

In the present study, we aimed to test the association between the correct function of the left ventral white matter pathways and semantic processing (dual stream models for language processing, Hickok & Poeppel, 2004), using a new set of language tasks during intraoperative electrical stimulation at white matter level. Additionally, we evaluated brain regions needed for correct performance on the different semantic tasks using lesion-symptom analyses (voxel lesion-symptom mapping and track-wise lesion analysis) in a sample of 62 candidates for the awake brain surgery. We found that electrical stimulation in the vicinity of the inferior longitudinal and inferior fronto-occipital fasciculi disturbed performance on semantic processing tasks.

Working Memory Deficits After Lesions Involving the Supplementary Motor Area.

The Supplementary Motor Area (SMA)-located in the superior and medial aspects of the superior frontal gyrus-is a preferential site of certain brain tumors and arteriovenous malformations, which often provoke the so-called SMA syndrome. The bulk of the literature studying this syndrome has focused on two of its most apparent symptoms: contralateral motor and speech deficits. Surprisingly, little attention has been given to working memory (WM) even though neuroimaging studies have implicated the SMA in this cognitive process.

Involvement of the middle frontal gyrus in language switching as revealed by electrical stimulation mapping and functional magnetic resonance imaging in bilingual brain tumor patients.

Neural basis of language switching and the cognitive models of bilingualism remain controversial. We explored the functional neuroanatomy of language switching implementing a new multimodal protocol assessing neuropsychological, functional magnetic resonance and intraoperative electrical stimulation mapping results. A prospective series of 9 Spanish-Catalan bilingual candidates for awake brain surgery underwent a specific language switching paradigm implemented both before and after surgery, throughout the electrical stimulation procedure and during functional magnetic resonance both pre- and postoperatively.

Unraveling the Role of the Hippocampus in Reversal Learning.

Research in reversal learning has mainly focused on the functional role of dopamine and striatal structures in driving behavior on the basis of classic reinforcement learning mechanisms. However, recent evidence indicates that, beyond classic reinforcement learning adaptations, individuals may also learn the inherent task structure and anticipate the occurrence of reversals. A candidate structure to support such task representation is the hippocampus, which might create a flexible representation of the environment that can be adaptively applied to goal-directed behavior.

Cross-situational word learning in aphasia.

Human learners can resolve referential ambiguity and discover the relationships between words and meanings through a cross-situational learning (CSL) strategy. Some people with aphasia (PWA) can learn word-referent pairings under referential uncertainty supported by online feedback. However, it remains unknown whether PWA can learn new words cross-situationally and if such learning ability is supported by statistical learning (SL) mechanisms.

Auditory Target and Novelty Processing in Patients with Unilateral Hippocampal Sclerosis: A Current-Source Density Study.

The capacity to respond to novel events is crucial for adapting to the constantly changing environment. Here, we recorded 29-channel Event Related Brain Potentials (ERPs) during an active auditory novelty oddball paradigm and used for the first time Current Source Density-transformed Event Related Brain Potentials and associated time-frequency spectra to study target and novelty processing in a group of epileptic patients with unilateral damage of the hippocampus (N = 18) and in healthy matched control participants (N = 18). Importantly, we used Voxel-Based Morphometry to ensure that our group of patients had a focal unilateral damage restricted to the hippocampus and especially its medial part.

Age of language acquisition and cortical language organization in multilingual patients undergoing awake brain mapping.

OBJECTIVE Most knowledge regarding the anatomical organization of multilingualism is based on aphasiology and functional imaging studies. However, the results have still to be validated by the gold standard approach, namely electrical stimulation mapping (ESM) during awake neurosurgical procedures. In this ESM study the authors describe language representation in a highly specific group of 13 multilingual individuals, focusing on how age of acquisition may influence the cortical organization of language.

Words are not enough: nonword repetition as an indicator of arcuate fasciculus integrity during brain tumor resection.

OBJECTIVE Subcortical electrical stimulation during brain surgery may allow localization of functionally crucial white matter fibers and thus tailoring of the tumor resection according to its functional limits. The arcuate fasciculus (AF) is a white matter bundle connecting frontal, temporal, and parietal cortical areas that is often disrupted by left brain lesions. It plays a critical role in several cognitive functions related to phonological processing, but current intraoperative monitoring methods do not yet allow mapping of this tract with sufficient precision.

Novel word acquisition in aphasia: Facing the word-referent ambiguity of natural language learning contexts.

Recent research suggests that some people with aphasia preserve some ability to learn novel words and to retain them in the long-term. However, this novel word learning ability has been studied only in the context of single word-picture pairings. We examined the ability of people with chronic aphasia to learn novel words using a paradigm that presents new word forms together with a limited set of different possible visual referents and requires the identification of the correct word-object associations on the basis of online feedback.

Music supported therapy promotes motor plasticity in individuals with chronic stroke.

Novel rehabilitation interventions have improved motor recovery by induction of neural plasticity in individuals with stroke. Of these, Music-supported therapy (MST) is based on music training designed to restore motor deficits. Music training requires multimodal processing, involving the integration and co-operation of visual, motor, auditory, affective and cognitive systems.

Electrical stimulation mapping of nouns and verbs in Broca's area.

Electric stimulation mapping (ESM) is frequently used during brain surgery to localise higher cognitive functions to avoid post-chirurgical disabilities. Experiments with brain imaging techniques and neuropsychological studies showed differences in the cortical representation and processing of nouns and verbs. The goal of the present study was to investigate whether electric stimulation in specific sites in the frontal cortex disrupted noun and verb production selectively.

Interhemispheric microstructural connectivity in bitemporal lobe epilepsy with hippocampal sclerosis.

Temporal lobe epilepsy (TLE) is the most common form of focal epilepsy. The most frequent pathologic finding in this condition is hippocampal sclerosis (HS). In addition, in a small proportion (14-23%) of refractory TLE patients, the presence of HS is bilateral.

Morphological derivation overflow as a result of disruption of the left frontal aslant white matter tract.

The frontal aslant tract (FAT) is a recently described major connection between the preSMA and Broca's area, whose functional role remains undefined. In this study we examined a patient presenting a morphological overregularization strategy in a verb generation task during awake surgery. This specific language deficit coincided with brain tumor resection at the level of the left FAT.

Speech segmentation in aphasia.

Background: Speech segmentation is one of the initial and mandatory phases of language learning. Although some people with aphasia have shown a preserved ability to learn novel words, their speech segmentation abilities have not been explored.

Aims: We examined the ability of individuals with chronic aphasia to segment words from running speech via statistical learning.

Circulating progenitor cells during exercise, muscle electro-stimulation and intermittent hypobaric hypoxia in patients with traumatic brain injury: a pilot study.

Background: Circulating progenitor cells (CPC) treatments may have great potential for the recovery of neurons and brain function.

Objective: To increase and maintain CPC with a program of exercise, muscle electro-stimulation (ME) and/or intermittent-hypobaric-hypoxia (IHH), and also to study the possible improvement in physical or psychological functioning of participants with Traumatic Brain Injury (TBI).

Methods: Twenty-one participants.

Atypical language organization in temporal lobe epilepsy revealed by a passive semantic paradigm.

Background: Mesial temporal lobe epilepsy (MTLE) is the most common type of focal epilepsy in adults and can be successfully cured by surgery. One of the main complications of this surgery however is a decline in language abilities. The magnitude of this decline is related to the degree of language lateralization to the left hemisphere.

Antithyroid antibodies as a potential marker of autoimmune-mediated late onset temporal lobe epilepsy.

Unlabelled: In one third of patients with epilepsy starting in adulthood the aetiology remains undetermined. Some patients with late onset temporal lobe epilepsy (TLE) together with memory decline have elevated antithyroid antibodies.

Purpose: To compare the prevalence of antithyroid antibodies (aTR-ab) in adult onset temporal lobe epilepsy (TLE) patients with known and unknown TLE aetiology (N=42).

Losing control of your languages: a case study.

Bilingual speakers are usually quite good at restricting their lexicalization output to the desired language while preventing all sorts of language intrusions from the language not in use. However, brain damage can affect these abilities of language control, leading to striking and flagrant linguistic behaviours, such as pathological language mixing (pLM) and pathological switching (pLS). In this paper we report the performance of a Catalan-Spanish bilingual individual (R.

Intraoperative electrical stimulation of language switching in two bilingual patients.

Background: Language switching (LS) is an important phenomena usually observed in some bilingual communities. The ability to switch languages is a very fast, efficient and flexible process, being a fundamental aspect of bilingual efficient language communication. The aim of the present study was to characterize the specific role of non-language specific prefrontal regions in the neural network involved in LS in bilingual patients, during awake brain surgery and using electrical stimulation mapping (ESM).