183 research outputs found
Neurobehavioral changes in people with post-stroke aphasia
At present, research on neurobehavioral disorders in people with post-stroke aphasia is scarce, especially in Spanish. The objective of this study is to design a new scale on neurobehavioral change, the Scale of Neurobehavioral Affectation in Aphasia (EANA, in Spanish) and to evaluate 14 people affected by chronic post-stroke aphasia (mean age: 51/ DT: 7.2) together with their main informants. At the same time, psychiatric (Neuropsychiatric Inventory, Hospital Anxiety and Depression Scale, Stroke Aphasic Depression Questionnaire), cognitive (Mini Mental State examination, Informer Test) and functional instruments (Stroke and Aphaisa Quality of Life Scale and Barthel Index) have been used to provide a multidimensional description of the affected persons. The results show statistically significant neurobehavioral changes in multiple domains. According to the EANA, those affected with post-stroke aphasia communicate with less frequently, show more introversion, shyness, dependence and apathy, behave in a more infantile manner ("makes me grimaces"), in addition to showing heightened anxiety and impulsivity. Finally, the informants report more aggressive acts, both verbal (insults) and physical (throwing objects, hitting both objects as persons), that did not occur before the stroke. According to the psychiatric instruments, many of the affected cope with anxiety, agitation and apathy, as well as mild depression. At a cognitive level, affected individuals show mild to moderate deficits, especially in working memory and temporal orientation. Functionally most individuals maintain a medium-high level of functional independence in daily activities. These findings support the inclusion of recommendations for the routine assessment and management of neurobehavioral changes to help optimize long-term recovery in people with stroke and aphasia.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Aphasia with anatomical isolation of the language area: A reanalysis on the light of modern neuroimaging techniques
Introduction : Goldstein (1948) and Geschwind (1968), based in data derived from anatomical post-mortem studies, postulated that the disconnection of the perisylvian language areas (PSLA) from other cortical areas was responsible for impairments in spontaneous speech and language comprehension with preservation of verbal repetition and echolalia (isolation of speech area). Nevertheless, other mechanisms (right hemisphere or bilateral hypotheses) underlying echolalic repetition have been proposed. Herein, we examined the structure and function of the PSLAs in two cases of aphasia with echolalic repetition and isolation of the left PSLA.
Methods : Two patients with chronic post-stroke aphasia associated to isolation of the left PSLA were studied. Both patients underwent cognitive-language assessment and multimodal imaging. In patient 1 (p1), structural MRI, diffusion tensor imaging (DTI), functional MRI (fMRI) during repetition of words and non-words, resting
state fMRI (rsfMRI) were acquired, whereas only structural MRI was performed in patient 2 (p2). The Tractotron software was used to examine the severity of disconnection in each language-related white matter tract in both patients. We quantified the severity of the disconnection by measuring the proportion of each tract that was affected. 18FDG-PET was also acquired in both patients.
Results : P1 had a mixed transcortical aphasia and p2 had a transcortical sensory/anomic aphasia. In both, the
MRI showed separate left anterior and posterior lesions with relative preservation of the PSLA. In both, 18FDG-PET revealed significant decrements of metabolic activity in areas of the left PSLA, although some parts showed normal metabolic activity. In p1 the left arcuate fasciculus (AF) and the inferior fronto-occipital fasciculi (IFOF) could not be reconstructed. fMRI showed perilesional activity in the left hemisphere and increased activity in the right during word repetition. rsfMRI showed compensatory activity in both hemispheres (right greater than left). Analysis with the Tractotron software revealed disconnection of both the AF and the IFOF in the left hemisphere of both patients.
Discussion : Although some parts of the left PSLA had preserved metabolic activity in both patients, our neuroimaging data revealed that preserved repetition ability did not rely exclusively on the residual activity of the left PSLA. In support, the connectivity between different components of the left PSLA was severely affected. This coupled with the increased metabolic activity of the right PSLA supports the bilateral hypothesis of residual repetition in transcortical aphasias.
References : Goldstein, K. (1948). Language and Language Disturbances.
Geschwind, et al. (1968). Neuropsychologia 6, 327–340.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec
Factores asociados al rendimiento académico en la asignatura de Psicobiología: Personalidad, constancia en el esfuerzo e implicación académica
El Grado en Psicología contiene asignaturas de base biológica que los estudiantes perciben de alta dificultad y en las que muestran bajo rendimiento. El objetivo es estudiar la relación entre variables de personalidad, constancia en el esfuerzo e implicación académica en el rendimiento académico de la asignatura “Fundamentos de Psicobiología”.
Metodología: 91 estudiantes matriculados en la asignatura “Fundamentos de Psicobiología” de la Universidad de Málaga completaron cuestionarios dirigidos a evaluar las variables de interés: (i) versión española del Big Five Personality Trait Short Questionnaire (BFPTSQ); cuestionario GRIT, que mide la constancia en el esfuerzo motivado; y la versión española del Utrecht Work Engagement Scale (UWES), que mide la implicación académica. Para evaluar el rendimiento académico, se consideraron las notas individuales del examen teórico final. La muestra se dividió en dos grupos en base a la nota final: aprobados y suspensos, y se compararon las puntuaciones obtenidas en las escalas usando el test t de student para muestras independientes. Además, se calculó la correlación entre la nota final y las variables analizadas mediante el coeficiente de correlación de Pearson.
Resultados: los alumnos aprobados (48) en el examen final mostraron puntuaciones más altas en la dimensión responsabilidad del BFPTSQ (t(89)=2.93, p=.004), GRIT (t(89)=2.10, p=.038) y UWES (t (89)=2.32, p=.023) que los suspensos (43). Se halló una correlación significativa entre nota final y puntuaciones en responsabilidad del BFPTSQ, GRIT y UWES (todas las p<.001).
Conclusión: Factores individuales como la dimensión de personalidad “Responsabilidad”, constancia en el esfuerzo y compromiso con la asignatura se asocian al éxito académico en la asignatura Fundamentos de Psicobiología. La identificación de las variables asociadas a un mejor rendimiento abre la posibilidad de incorporar estrategias docentes innovadoras dirigidas a modular estos factores.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Attentional effects on rule extraction and consolidation from speech.
Incidental learning plays a crucial role in the initial phases of language acquisition. However this knowledge derived from implicit learning, which is based on prediction-based mechanisms, may become explicit. The role that attention plays in the formation of implicit and explicit knowledge of the learned material is unclear. In the present study, we investigated the role that attention plays in the acquisition of non-adjacent rule learning from speech. In addition, we also tested whether the amount of attention during learning changes the representation of the learned material after a 24h delay containing sleep. For that, we developed an experiment run on two consecutive days consisting on the exposure to an artificial language that contained nonadjacent dependencies (rules) between words whereas different conditions were established to manipulate the amount of attention given to the rules (target and non-target conditions). Furthermore, we used both indirect and direct measures of learning that are more sensitive to implicit and explicit knowledge respectively. Whereas the indirect measures indicated that learning of the rules occurred regardless of attention, more explicit judgments after learning showed differences in the type of learning reached under the two attention conditions. 24 hours later, indirect measures showed no further improvements during additional language exposure and explicit judgments indicated that only the information more robustly learned in the previous day was consolidated
The impact of early and late literacy on the functional connectivity of vision and
Introduction: Learning to read leads to functional and structural changes in the cortical regions related to
vision and language. The visual word-form area (VWFA) is though to play a key role in the interaction between
these two systems (Dehaene et al. 2015). For instance, the VWFA is activated not only from bottom-up during
reading but also in a top-down manner during speech listening without visual stimulation (Dehaene et al. 2010).
The objective of this study was twofolded: how literacy acquisition affects four intrinsic functional connectivity
networks related to vision and language (a dorsal language [DLN], a bilateral auditory [AN], a low-level
[LLVN] and a high-level visual [HLVN] networks); and to explore the role of the VWFA as an interface between
high-level vision and language functions.
Methods: Independent component analysis (ICA) was applied to functional magnetic resonance imaging data
from 40 adult participants with variable levels of literacy (illiterate, late literate and early literate). The four
functional connectivity networks were compared across groups using dual-regression (Filippini et al. 2009). In
addition, we directly explored the functional connectivity between the VWFA and each of the studied networks.
Finally, the strengh of connectivity between the VWFA and each network was compared across groups and
correlated with individual reading fluency scores.
Results: ICA produced 40 networks, and spatial crosscorrelation was used to identify the four networks of
interest. Literacy was positively correlated with increased connectivity within the four networks. A major
difference separating early literate from illiterate and late literate subjects was found. The connectivity between
the VWFA and the DLN increased with literacy. Conversely, the strength of connectivity between the VWFA and
the HLVN correlated negatively with literacy. Finally, , the HLVN-VWFA connectivity was negatively correlated
with reading scores while the connectivity between the DLN-VWFA was positively correlated with reading
scores.
Discussion:Literacy has a strong influence on the visual and language functional networks. Literacy modifies
the VWFA connectivity, by making it functionally closer to the language system, and more distinct from other
associative visual areas that do not contribute to the reading process. The current results suggest that early
acquisition of literacy plays a critical role for the tuning of the functional brain architecture.
References: -Dehaene S et al. Nat Rev Neurosci.(2015)16:234 244
-Dehaene S et al. Science.(2010)330:1359–1364
-Filippini N et al. PNAS.(2009)106, 7209–7214Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
“Need to know” and the right temporal lobe: Impaired access to semantic knowledge in acquired obsessive-compulsive disorder?
Introduction : Idiopathic obsessive-compulsive disorder (I-OCD) has been linked to abnormalities in corticostriatal circuits. Few studies have examined if the same structures are also responsible of acquired OCD (A-OCD) or if damage to anatomically-connected brain regions (e.g., temporal lobes) are also implicated in its
pathogenesis. Additionally, there are some discrete obsessive-compulsive (OC) symptoms that by virtue of their presumed low occurrence and difficultly of categorization have received less attention. Amongst these, one intriguing and potentially severe type of obsessive thinking is the so-called “need to know” (NtK), a strong drive to know and obtain given information. In some patients this specific symptom, presumably resulting from impaired access to conceptual knowledge for specific verbal information (proper names, names of places), may be the principal or major feature of OCD symptomatology. We here report the cases of two male patients who developed “NtK” as the only OC symptomatology in association with malignant neoplasms involving the right temporal lobe and connected corticostriatal circuits.
Methods : We used Tractotron and Disconnectome map softwares in order to identify the regions of white matter damage overlap across both patients and the proportion of damage (lesion load) of each tract of interest for each patient. We quantified the severity of the disconnection by measuring the proportion of each tract of interest to be affected by each patient´s lesion by using Tractotron software. Additionally, Positron Emission Tomography was used in order to study metabolic abnormalities. The tracts of interest were: the uncinate fasciculus, the anterior commissure, the anterior thalamic radiations, the inferior fronto-occipital fasciculus and the inferior longitudinal fasciculus.
Results : There was a high overlap across brain lesions in patients 1 and 2. There was also a high overlap between areas that were affected (disconnected) due to the lesion. As expected, all the a priori selected pathways in the right hemisphere were affected since they cross the anterior part of the temporal lobe. Disconnection maps
and metabolic changes in our patients suggest that the expression of OC symptoms underpinned by a semantic deficit due to right temporal damage is secondary to involvement of the uncinate fasciculus linking the temporal pole with the orbitofrontal cortex.
Discussion : Data from the present study concur with previous research on A-OCD and current findings in I-OCD which suggest that the temporal lobes participate in the phenomenological expression of OCD. Also, patients with lesions in the anterior temporal lobe are prone to show a specific “Need to Know” symptoms phenomenologically similar to patients with semantic dementia in later stages. The expression of OC symptoms underpinned by a semantic deficit because of anterior right temporal lobe lesion, are due to a disconnection of the uncinate fasciculus and the orbitofrontal cortex. Further research about the neurological underpinnings of specific OCD subtypes, its evaluation and treatment, are essential.
References : Berthier ML et al. Neurology. (1996) 47: 353–61. Huey E et al. J Neuropsych Clin Neurosci (2008). 20(4):390-408
Keywords : Emotions & Social Cognition; patients; single case study; adults; psychiatric; lesion mapping, behavioural.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Turning the spotlight to cholinergic pharmacotherapy of the human language system
Even though language is essential in human communication, research on pharmacological therapies for language deficits in highly prevalent neurodegenerative and vascular brain diseases has received little attention. Emerging scientific evidence suggests that disruption of the cholinergic system may play an essential role in language deficits associated with Alzheimer's disease and vascular cognitive impairment, including post-stroke aphasia. Therefore, current models of cognitive processing are beginning to appraise the implications of the brain modulator acetylcholine in human language functions. Future work should be directed further to analyze the interplay between the cholinergic system and language, focusing on identifying brain regions receiving cholinergic innervation susceptible to modulation with pharmacotherapy to improve affected language domains. The evaluation of language deficits in pharmacological cholinergic trials for Alzheimer's disease and vascular cognitive impairment has thus far been limited to coarse-grained methods. More precise, fine-grained language testing is needed to refine patient selection for pharmacotherapy to detect subtle deficits in the initial phases of cognitive decline. Additionally, noninvasive biomarkers can help identify cholinergic depletion. However, despite the investigation of cholinergic treatment for language deficits in Alzheimer's disease and vascular cognitive impairment, data on its effectiveness are insufficient and controversial. In the case of post-stroke aphasia, cholinergic agents are showing promise, particularly when combined with speech-language therapy to promote trained-dependent neural plasticity. Future research should explore the potential benefits of cholinergic pharmacotherapy in language deficits and investigate optimal strategies for combining these agents with other therapeutic approaches.Funding for open access publishing: Universidad Málaga/CBUA. Guadalupe Dávila was supported by the Junta de Andalucía,
Spain (Grant: P20_00501). Marcelo L. Berthier has been supportedby the European Social Fund (FEDER: EQC2018-004803-P). María José Torres-Prioris was supported by a Margarita Salas postdoctoral fellowship by the University of Malaga, funded by the European Union, NextGenerationEU, and the Spanish Ministerio de Universidades.
Diana López-Barroso was supported by the Ayuda RYC2020-029495-I Ramón y Cajal funded by the MCIN/AEI/10.13039/501100011033 and by El FSE invierte en tu futuro; and by the Grant PID2021-127617NAI00 Proyecto de Generación de Conocimiento 2021 funded by MCIN/AEI/10.13039/501100011033 and FEDER Una manera de hacerEuropa. Funding for the open access charge: Universidad de Málaga/CBU
Language Learning Variability within the Dorsal and Ventral Streams as a Cue for Compensatory Mechanisms in Aphasia Recovery
Dorsal and ventral pathways connecting perisylvian language areas have been shown to be functionally and anatomically segregated. Whereas the dorsal pathway integrates the sensory-motor information required for verbal repetition, the ventral pathway has classically been associated with semantic processes. The great individual differences characterizing language learning through life partly correlate with brain structure and function within these dorsal and ventral language networks. Variability and plasticity within these networks also underlie inter-individual differences in the recovery of linguistic abilities in aphasia. Despite the division of labor of the dorsal and ventral streams, studies in healthy individuals have shown how the interaction of them and the redundancy in the areas they connect allow for compensatory strategies in functions that are usually segregated. In this mini-review we highlight the need to examine compensatory mechanisms between streams in healthy individuals as a helpful guide to choosing the most appropriate rehabilitation strategies, using spared functions and targeting preserved compensatory networks for brain plasticity
Beneficial effects of pharmacological treatment in post-stroke dynamic aphasia: a behavioural and neuroimaging study
Introduction : Dynamic Aphasia (DA) is a rare form of language disorder characterized by reduced spontaneous speech with preservation of other language functions. Two types of DA have been described: language-specific type (type I DA) and domain-general type (type II DA). In type I DA, deficits are selective for word and sentence generation, whereas in type II DA impairments affect discourse generation, narrative, fluency, and non-verbal generation tasks. There is little information on the treatment of DA. Although treatment with a cognitive enhancing drug (bromocriptine) improved outcome in previous studies, pharmacological interventions combining
two drugs acting on other neurotransmitter systems in DA have not been reported so far.
Methods : We report an open-label pharmacological single case study (n = 1) in a male patient with a chronic type I/II DA secondary to an ischemic infarction in the left fronto-opercular and insular regions. After baseline evaluation, the patient received donepezil 5 mg/day (2 months), donepezil 10 mg/day (2 months), donepezil 10
mg/day plus memantine 20 mg/day (4½ months) followed by a washout period (1½ months). No speech-language therapy was used. A comprehensive cognitive and language evaluation was carried out at baseline and at different endpoints. 18FDG-PET was performed at the four timepoints.
Results : Donepezil (5 mg/day) significantly improved type I DA features (normalization of verbs generation, p = 0.01), whereas donepezil (10 mg/day) improved some type II features (normalizing spontaneous speech, verbal
fluency and improving generation of novel thoughts, p = 0.004), along with improvement of executive-attentional functioning. Combined therapy further enhanced cognitive function, but did not additionally improved DA. 18 FDG-PET revealed significant reductions of perilesional hypometabolic activity mainly after donepezil (10 mg/day) and washout.
Discussion : Treatment with donepezil improved language deficits in a patient with chronic post-stroke type I/II DA. Combined therapy (donepezil plus memantine) further enhanced executive-attentional functioning. Beneficial changes were associated with improvements in perilesional metabolic activity.
References : Luria AR et al.Acta Neurologica et Psychiatrica (1967). Robinson G et al. Brain (1998).
Keywords : Language; patients; single case study; adults; cerebrovascular; behavioural, functional imaging.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Brain structural and functional correlates of the heterogenous progression of mixed transcortical aphasia
Mixed transcortical aphasia (MTCA) is characterized by non-fluent speech and comprehension deficits coexisting with preserved repetition. MTCA may evolve to less severe variants of aphasias or even to full language recovery. Mechanistically, MCTA has traditionally been attributed to a disconnection between the spared left perisylvian language network (PSLN) responsible for preserved verbal repetition, and damaged left extrasylvian networks, which are responsible for language production and comprehension impairments. However, despite significant advances in in vivo neuroimaging, the structural and functional status of the PSLN network in MTCA and its evolution has not been investigated. Thus, the aim of the present study is to examine the status of the PSLN, both in terms of its functional activity and structural integrity, in four cases
who developed acute post-stroke MTCA and progressed to different types of aphasia. For it, we conducted a neuroimaging-
behavioral study performed in the chronic stage of four patients. The behavioral profile of MTCA persisted in one patient,
whereas the other three patients progressed to less severe types of aphasias. Neuroimaging findings suggest that preserved
verbal repetition in MTCA does not always depend on the optimal status of the PSLN and its dorsal connections. Instead, the
right hemisphere or the left ventral pathway may also play a role in supporting verbal repetition. The variability in the clinical
evolution of MTCA may be explained by the varying degree of PSLN alteration and individual premorbid neuroanatomical
language substrates. This study offers a fresh perspective of MTCA through the lens of modern neuroscience and unveils
novel insights into the neural underpinnings of repetition.Funding for open access publishing: Universidad Málaga/CBUA.
This work was supported by the Spanish Ministry of Economy, Industry and Competitiveness, Instituto de Salud Carlos III under
Grant: PI16/01514 (MLB and GD) and by the Junta de Andalucía under Grant: P20_00501 (GD). MLB was funded by the European Social Fund (FEDER). DL-B was supported by the Ayuda RYC2020-029495-I Ramón y Cajal funded by the MCIN/AEI/10.13039/501100011033 and by El FSE invierte en tu futuro; and by the Grant PID2021-127617NA-I00 Proyecto de Generación de Conocimiento 2021 funded by MCIN/AEI /10.13039/501100011033/ and FEDER Una manera de hacer Europa. JP-P was funded by a PhD scholarship (FPU16/05198) from the Spanish Ministry of Education, Culture and Sport under the FPU
program. MJT-P was supported by a Margarita Salas postdoctoral fellowship by the University of Malaga, funded by the European Union– NextGenerationEU – and the Spanish Ministerio de Universidades, and by a mobility grant from the Spanish Ministry of Universities under the José Castillejo program
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