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1.
Appetite ; 160: 105122, 2021 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-33453336

RESUMEN

Due to the spread of COVID 2019, the Italian government imposed a lockdown on the national territory. Initially, citizens were required to stay at home and not to mix with others outside of their household (Phase 1); eventually, some of these restrictions were lifted (Phase 2). To investigate the impact of lockdown on emotional and binge eating, an online survey was conducted to compare measures of self-reported physical (BMI), psychological (Alexithymia), affective (anxiety, stress, and depression) and social (income, workload) state during Phase 1 and Phase 2. Data from 365 Italian residents showed that increased emotional eating was predicted by higher depression, anxiety, quality of personal relationships, and quality of life, while the increase of bingeing was predicted by higher stress. Moreover, we showed that higher alexithymia scores were associated by increased emotional eating and higher BMI scores were associated with both increased emotional eating and binge eating. Finally, we found that from Phase 1 to Phase 2 binge and emotional eating decreased. These data provide evidence of the negative effects of isolation and lockdown on emotional wellbeing, and, relatedly, on eating behaviour.


Asunto(s)
COVID-19/psicología , Conducta Alimentaria/psicología , Pandemias , Distrés Psicológico , Adolescente , Adulto , Síntomas Afectivos/epidemiología , Anciano , Índice de Masa Corporal , Bulimia/epidemiología , Emociones , Femenino , Humanos , Italia , Masculino , Persona de Mediana Edad , Distanciamiento Físico , Encuestas y Cuestionarios , Adulto Joven
2.
J Neurosci ; 39(22): 4332-4343, 2019 05 29.
Artículo en Inglés | MEDLINE | ID: mdl-30902872

RESUMEN

EEG studies in healthy humans have highlighted that alpha-band activity is relatively reduced over the occipital-parietal areas of the hemisphere contralateral to the direction of spatial attention. Here, we investigated the hemispheric distribution of alpha during orienting of attention in male and female right brain-damaged patients with left spatial neglect. Temporal spectral evolution showed that in patients with neglect alpha oscillations over the damaged hemisphere were pathologically enhanced both during the baseline-fixation period that preceded cued orienting (capturing tonic alpha changes) and during orienting with leftward, rightward, or neutral-bilateral spatial cues (reflecting phasic alpha changes). Patients without neglect showed a similar though significantly less enhanced hemispheric asymmetry. Healthy control subjects displayed a conventional decrease of alpha activity over the hemisphere contralateral to the direction of orienting. In right-brain-damaged patients, neglect severity in the line bisection task was significantly correlated both with tonic alpha asymmetry during the baseline period and with phasic asymmetries during orienting of attention with neutral-bilateral and leftward cues. Asymmetries with neutral-bilateral and leftward cues were correlated with lesion of white matter tracts linking frontal with parietal-occipital areas. These findings show that disruption of rostrocaudal white matter connectivity in the right hemisphere interferes with the maintenance of optimal baseline tonic levels of alpha and the phasic modulation of alpha activity during shifts of attention. The hemispheric distribution of alpha activity can be used as a diagnostic tool for acquired pathological biases of spatial attention due to unilateral brain damage.SIGNIFICANCE STATEMENT Alpha desynchronization over the hemisphere contralateral to the attended side of space is a reliable marker of attentional orienting in the healthy human brain: can the same marker be used to spot and quantify acquired disturbances of spatial attention after unilateral brain injuries? Are pathological modifications in the hemispheric distribution of alpha specifically linked to attentional neglect for one side of space? We show that in patients with right brain damage the pathological enhancement of alpha oscillations over the parietal and occipital areas of the injured hemisphere is correlated with reduced awareness for the left side of space and with the lesion of white matter pathways that subserve frontal modulation of alpha activity in posterior brain areas.


Asunto(s)
Ritmo alfa/fisiología , Atención/fisiología , Lateralidad Funcional/fisiología , Orientación Espacial/fisiología , Trastornos de la Percepción/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad
3.
Brain Cogn ; 123: 103-109, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29550505

RESUMEN

Impulsivity, conceptualized as impulsive personality trait, poor inhibitory control and enhanced reward sensitivity, has been strongly linked to obesity. In particular, a disequilibrium between cognitive control and reward sensitivity has been observed in obese individuals in both behavioural and imaging studies. While this issue has been widely investigated in children and adults, it has received little attention in older adults. Here, obese and non-obese participants aged between 40 and 70 years completed the Barratt Impulsiveness scale (assessing motor, non-planning and attentional impulsiveness), a Go/no-go task with foods and non-foods (assessing inhibitory control) and a reward sensitivity battery with high and low caloric foods (assessing liking, wanting, tastiness and frequency of consumption). We observed that participants with higher BMI reported increased wanting for high calorie foods, but did not show poorer inhibitory control. Interestingly, participants who scored lower on the MMSE reported to consume high calorie more than low calorie foods. Finally, those who presented low scores on non-planning and motor impulsiveness subscales reported higher tastiness ratings for low calorie foods. These results show that increased reward sensitivity but not reduced inhibitory control may characterize higher BMI during aging. Importantly, they also highlight new findings concerning food preferences among older adults.


Asunto(s)
Peso Corporal/fisiología , Conducta Impulsiva/fisiología , Obesidad/psicología , Recompensa , Adulto , Anciano , Atención/fisiología , Femenino , Preferencias Alimentarias/psicología , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas
4.
Neurocase ; 22(4): 400-9, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27327171

RESUMEN

Patients with different types of dementia may exhibit pathological eating habits, including food fads, hyperphagia, or even ingestion of inanimate objects. Several findings reveal that such eating alterations are more common in patients with frontotemporal dementia (FTD) than other types of dementia. Moreover, eating alterations may differ between the two variants of the disease, namely the behavioral variant and semantic dementia (SD). In this review, we summarized evidences regarding four areas: eating and body weight alterations in FTD, the most common assessment methods, anatomical correlates of eating disorders, and finally, proposed underlying mechanisms. An increasing understanding of the factors that contribute to eating abnormalities may allow first, a better comprehension of the clinical features of the disease and second, shed light on the mechanism underlying eating behaviors in the normal population.


Asunto(s)
Trastornos de Alimentación y de la Ingestión de Alimentos , Demencia Frontotemporal , Trastornos de Alimentación y de la Ingestión de Alimentos/etiología , Trastornos de Alimentación y de la Ingestión de Alimentos/patología , Trastornos de Alimentación y de la Ingestión de Alimentos/fisiopatología , Demencia Frontotemporal/complicaciones , Demencia Frontotemporal/patología , Demencia Frontotemporal/fisiopatología , Humanos
5.
Cereb Cortex ; 24(3): 691-706, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23162045

RESUMEN

The exact anatomical localization of right hemisphere lesions that lead to left spatial neglect is still debated. The effect of confounding factors such as acute diaschisis and hypoperfusion, visual field defects, and lesion size may account for conflicting results that have been reported in the literature. Here, we present a comprehensive anatomical investigation of the gray- and white matter lesion correlates of left spatial neglect, which was run in a sample 58 patients with subacute or chronic vascular strokes in the territory of the right middle cerebral artery. Standard voxel-based correlates confirmed the role played by lesions in the posterior parietal cortex (supramarginal gyrus, angular gyrus, and temporal-parietal junction), in the frontal cortex (frontal eye field, middle and inferior frontal gyrus), and in the underlying parietal-frontal white matter. Using a new diffusion tensor imaging-based atlas of the human brain, we were able to run, for the first time, a detailed analysis of the lesion involvement of subcortical white matter pathways. The results of this analysis revealed that, among the different pathways linking parietal with frontal areas, damage to the second branch of the superior longitudinal fasciculus (SLF II) was the best predictor of left spatial neglect. The group study also revealed a subsample of patients with neglect due to focal lesion in the lateral-dorsal portion of the thalamus, which connects the premotor cortex with the inferior parietal lobule. The relevance of fronto-parietal disconnection was further supported by complete in vivo tractography dissection of white matter pathways in 2 patients, one with and the other without signs of neglect. These 2 patients were studied both in the acute phase and 1 year after stroke and were perfectly matched for age, handedness, stroke onset, lesion size, and for cortical lesion involvement. Taken together, the results of the present study support the hypothesis that anatomical disconnections leading to a functional breakdown of parietal-frontal networks are an important pathophysiological factor leading to chronic left spatial neglect. Here, we propose that different loci of SLF disconnection on the rostro-caudal axis can also be associated with disconnection of short-range white matter pathways within the frontal or parietal areas. Such different local disconnection patterns can play a role in the important clinical variability of the neglect syndrome.


Asunto(s)
Leucoencefalopatías/etiología , Trastornos de la Percepción/complicaciones , Trastornos de la Sensación/etiología , Interfaz Usuario-Computador , Campos Visuales/fisiología , Adulto , Anciano , Imagen de Difusión por Resonancia Magnética , Femenino , Lateralidad Funcional , Humanos , Procesamiento de Imagen Asistido por Computador , Modelos Lineales , Masculino , Persona de Mediana Edad , Fibras Nerviosas Mielínicas/patología , Trastornos de la Percepción/etiología , Desempeño Psicomotor/fisiología , Accidente Cerebrovascular/complicaciones
6.
Appetite ; 84: 204-11, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25453591

RESUMEN

Research on eating behaviours has extensively highlighted that cognitive systems interact with the metabolic system in driving food intake and in influencing body weight regulation. Parkinson's disease is a good model for studying these complex interactions since alterations in both body weight and cognitive domains have been frequently reported among these patients. Interestingly, even if different non-motor symptoms may characterize the course of the disease, their contribution to weight and food preference has been poorly investigated. This review describes body weight alterations and eating habits in patients with Parkinson's disease, including those who underwent deep brain stimulation surgery. In particular, the review considers the link between non-motor symptoms, affecting sensory perception, cognition, mood and motivation, and food intake and weight alterations. The take home message is twofold. First, we recommend a comprehensive approach in order to develop effective strategies in the management of patients' weight. Second, we also suggest that investigating this issue in patients with Parkinson's disease may provide some useful information about the mechanisms underlying food and weight regulation in healthy subjects.


Asunto(s)
Peso Corporal , Ingestión de Alimentos/psicología , Ingestión de Energía , Conducta Alimentaria/psicología , Obesidad/psicología , Enfermedad de Parkinson/psicología , Afecto , Animales , Apetito , Cognición , Estimulación Encefálica Profunda , Preferencias Alimentarias , Humanos , Motivación , Obesidad/complicaciones , Obesidad/prevención & control , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/cirugía , Sensación
7.
J Int Neuropsychol Soc ; 20(10): 1004-14, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25373767

RESUMEN

Multiple sclerosis (MS) may be associated with impaired perception of facial emotions. However, emotion recognition mediated by bodily postures has never been examined in these patients. Moreover, several studies have suggested a relation between emotion recognition impairments and alexithymia. This is in line with the idea that the ability to recognize emotions requires the individuals to be able to understand their own emotions. Despite a deficit in emotion recognition has been observed in MS patients, the association between impaired emotion recognition and alexithymia has received little attention. The aim of this study was, first, to investigate MS patient's abilities to recognize emotions mediated by both facial and bodily expressions and, second, to examine whether any observed deficits in emotions recognition could be explained by the presence of alexithymia. Thirty patients with MS and 30 healthy matched controls performed experimental tasks assessing emotion discrimination and recognition of facial expressions and bodily postures. Moreover, they completed questionnaires evaluating alexithymia, depression, and fatigue. First, facial emotion recognition and, to a lesser extent, bodily emotion recognition can be impaired in MS patients. In particular, patients with higher disability showed an impairment in emotion recognition compared with patients with lower disability and controls. Second, their deficit in emotion recognition was not predicted by alexithymia. Instead, the disease's characteristics and the performance on some cognitive tasks significantly correlated with emotion recognition. Impaired facial emotion recognition is a cognitive signature of MS that is not dependent on alexithymia.


Asunto(s)
Síntomas Afectivos/etiología , Tipificación del Cuerpo/fisiología , Emociones/fisiología , Expresión Facial , Esclerosis Múltiple/complicaciones , Trastornos de la Percepción/etiología , Adulto , Síntomas Afectivos/diagnóstico , Análisis de Varianza , Discriminación en Psicología , Femenino , Humanos , Masculino , Esclerosis Múltiple/psicología , Pruebas Neuropsicológicas , Trastornos de la Percepción/diagnóstico , Estimulación Luminosa , Postura , Escalas de Valoración Psiquiátrica , Estadística como Asunto , Encuestas y Cuestionarios
8.
Schizophr Res ; 271: 271-280, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39068879

RESUMEN

BACKGROUND: The ability to value rewards is crucial for adaptive behavior and is influenced by the time and effort required to obtain them. Impairments in these computations have been observed in patients with schizophrenia and may be present in individuals with subclinical psychotic symptoms (PS). METHODS: In this study, we employed delay and effort-discounting tasks with food rewards in thirty-nine participants divided into high and low levels of PS. We investigated the underlying mechanisms of effort-discounting through computational modelling of dopamine prefrontal and subcortical circuits and the electrophysiological biomarker of both delay and effort-discounting alterations through resting-state frontal alpha asymmetry (FAA). RESULTS: Results revealed greater delay discounting in the High PS group compared to the Low PS group but no differences in the effort discounting task. However, in this task, the same levels of estimated dopamine release were associated with a lower willingness to exert effort for high-calorie food rewards in High PS participants compared to Low PS participants. Although there were no significant differences in FAA between the High PS and Low PS groups, FAA was significantly associated with the severity of participants' negative symptoms. CONCLUSIONS: Our study suggests that the dysfunction in temporal and effort cost computations, seen in patients with schizophrenia, may be present in individuals with subclinical PS. These findings provide valuable insight into the early vulnerability markers (behavioral, computational, and electrophysiological) for psychosis, which may aid in the development of preventive interventions. These findings are preliminary and warrant further investigation.


Asunto(s)
Descuento por Demora , Trastornos Psicóticos , Recompensa , Humanos , Masculino , Femenino , Trastornos Psicóticos/fisiopatología , Adulto , Descuento por Demora/fisiología , Adulto Joven , Electroencefalografía , Ritmo alfa/fisiología , Esquizofrenia/fisiopatología , Simulación por Computador , Dopamina/metabolismo
9.
Brain ; 135(Pt 8): 2492-505, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22577222

RESUMEN

Spatial reasoning has a relevant role in mathematics and helps daily computational activities. It is widely assumed that in cultures with left-to-right reading, numbers are organized along the mental equivalent of a ruler, the mental number line, with small magnitudes located to the left of larger ones. Patients with right brain damage can disregard smaller numbers while mentally setting the midpoint of number intervals. This has been interpreted as a sign of spatial neglect for numbers on the left side of the mental number line and taken as a strong argument for the intrinsic left-to-right organization of the mental number line. Here, we put forward the understanding of this cognitive disability by discovering that patients with right brain damage disregard smaller numbers both when these are mapped on the left side of the mental number line and on the right side of an imagined clock face. This shows that the right hemisphere supports the representation of small numerical magnitudes independently from their mapping on the left or the right side of a spatial-mental layout. In addition, the study of the anatomical correlates through voxel-based lesion-symptom mapping and the mapping of lesion peaks on the diffusion tensor imaging-based reconstruction of white matter pathways showed that the rightward bias in the imagined clock-face was correlated with lesions of high-level middle temporal visual areas that code stimuli in object-centred spatial coordinates, i.e. stimuli that, like a clock face, have an inherent left and right side. In contrast, bias towards higher numbers on the mental number line was linked to white matter damage in the frontal component of the parietal-frontal number network. These anatomical findings show that the human brain does not represent the mental number line as an object with an inherent left and right side. We conclude that the bias towards higher numbers in the mental bisection of number intervals does not depend on left side spatial, imagery or object-centred neglect and that it rather depends on disruption of an abstract non-spatial representation of small numerical magnitudes.


Asunto(s)
Lesiones Encefálicas/diagnóstico , Lesiones Encefálicas/psicología , Conceptos Matemáticos , Desempeño Psicomotor/fisiología , Percepción Espacial/fisiología , Adulto , Anciano , Lesiones Encefálicas/patología , Humanos , Masculino , Persona de Mediana Edad
10.
PLoS One ; 18(6): e0278496, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37279254

RESUMEN

Although emotion and olfaction are closely linked, only a few studies have investigated olfactory processing in alexithymia, a condition characterized by altered emotional processing. These results do not allow comprehensive conclusions on whether individuals with alexithymia present lower olfactory abilities or only altered affective reactions and awareness of odors. Three pre-registered experiments were conducted to clarify this relation. We assessed olfactory functions, the affective qualities of odors, the awareness of odors, the attitudes towards them, and the ability to form olfactory images in the mind. Bayesian statistics were used to assess differences between low, medium and high alexithymia groups, and Linear Mixed Models (LMMs) were applied to investigate the modulation of the affective and cognitive components of alexithymia. We observed that individuals with a high level of alexithymia presented the same olfactory abilities, and did not show differences in their rating of odors compared to individuals with low alexithymia levels, while they reported lower levels of social and common odor awareness and a more indifferent attitude towards odors. Olfactory imagery was not affected by alexithymia level, and the affective and cognitive components of alexithymia, when considered separately, modulated olfactory perception differently. Learning more about olfactory perception in individuals with alexithymia leads to a better understanding of how alexithymia impacts the perception of hedonic stimuli coming from different sensory modalities. Our results imply that treatment goals for alexithymia should be the enhancement of the conscious perception of odors, supporting the use of mindfulness-based protocols in the alexithymia treatment.


Asunto(s)
Percepción Olfatoria , Olfato , Humanos , Odorantes , Síntomas Afectivos/psicología , Teorema de Bayes , Actitud
11.
J Cogn Enhanc ; 6(3): 389-401, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35729871

RESUMEN

Executive functions include functions such as planning, working memory, inhibition, mental flexibility, and action monitoring and initiation, and are essential to carry out an independent everyday life. Individuals suffering from brain injury, such as a stroke, very commonly experience executive deficits that reduce the capacity to regain functional independence. In recent years, there has been a growing interest in developing tablet computer-based cognitive training programs for stroke patients and healthy aging adults since such programs can be included in non-supervised environments. In this respect, we described and evaluated the usability of a novel tablet application (app) for executive function training, developed in the context of the MEMORI-net project, a cross-border Italy-Slovenia program for the rehabilitation of stroke patients. We conducted a pilot study with a non-clinical sample of 16 participants to obtain information about the usability of the sFEra APP. Our descriptive analyses suggest that most users were satisfied with the overall experience and the app was highly usable, and instructions were clear, even with little previous experience with tablet applications. Acceptability and effectiveness will need to be evaluated in a clinical randomized controlled study.

12.
J Neurol ; 269(3): 1557-1565, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34333702

RESUMEN

Parkinson's disease (PD) patients with impulse control disorders (ICD) frequently report hypersensitivity to rewards. However, a few studies have explored the effectiveness of modulation techniques on symptoms experienced by these patients. In this study, we assessed the effect of anodal tDCS over the DLPFC on reward responsiveness and valuation in PD patients with ICD. 43 participants (15 PD patients with ICD, 13 PD without ICD, and 15 healthy matched controls) were asked to perform a reward-craving test employing both explicit (self-ratings of liking and wanting) and implicit (heart rate and skin conductance response) measures, as well as two temporal discounting tasks with food and money rewards. Each participant performed the experimental tasks during active anodal tDCS of the left dorsolateral prefrontal cortex (DLPFC), anodal tDCS of the primary motor cortex (M1), and sham tDCS. Results showed increased wanting and a steeper temporal discounting of rewards in PD with ICD compared to the other groups. Moreover, we found that PD without ICD exhibit reduced liking for rewards. tDCS results capable to modulate the altered intensity of PD patients' liking, but not wanting and temporal discounting of rewards in PD patients with ICD. These findings confirm that alterations in reward responsiveness and valuation are characteristics of impulse control disorders in patients with PD but suggest that anodal tDCS over the left DLPFC is not capable to influence these processes. At the same time, they provide new insight into affective experience of rewards in PD.


Asunto(s)
Descuento por Demora , Trastornos Disruptivos, del Control de Impulso y de la Conducta , Enfermedad de Parkinson , Estimulación Transcraneal de Corriente Directa , Trastornos Disruptivos, del Control de Impulso y de la Conducta/etiología , Trastornos Disruptivos, del Control de Impulso y de la Conducta/terapia , Humanos , Enfermedad de Parkinson/terapia , Corteza Prefrontal , Recompensa , Estimulación Transcraneal de Corriente Directa/métodos
13.
Front Psychol ; 12: 630751, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33716896

RESUMEN

Following the COVID-19 pandemic, many countries worldwide have put lockdowns in place to prevent the virus from spreading. Evidence shows that lockdown measures can affect mental health; it is, therefore, important to identify the psychological characteristics making individuals more vulnerable. The present study aimed, first, to identify, through a cluster analysis, the psychological attributes that characterize individuals with similar psychological responses to the COVID-19 home confinement; second, to investigate whether different psychological characteristics, such as personality traits, alexithymia, and resilience, specifically influence anxiety, stress, and depression, depending on the scope of the confinement. We analyzed data from 393 participants who completed an online survey on their experiences during two different phases of the Italian lockdown, characterized by more or less strict measures of confinement. Two clusters were identified which included participants reporting a better (+ER) and worse (-ER) emotional response to the lockdown, respectively. Individuals in the -ER group showed lower emotional stability, resilience, and higher alexithymia. Moreover, even if lifting part of the restrictions decreased psychological distress among all participants, a reduction in perceived stress was observed only among individuals with high resilience. Finally, personality traits, alexithymia, and resilience differently affected depression, anxiety, and stress. Our results suggest that different psychological interventions should be planned depending on the context: mental health professionals should focus on enhancing the individuals' coping strategies to alleviate stress in emergencies, while long-term intervention aiming at alleviating anxiety and depressive symptoms should focus on alexithymic tendencies and personality constructs.

14.
Neurosci Lett ; 761: 136097, 2021 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-34237413

RESUMEN

Electrophysiological group studies in brain-damaged patients can be run to capture the EEG correlates of specific cognitive impairments. Nonetheless, this procedure is not adequate to characterize the inter-individual variability present in major neuropsychological syndromes. We tested the possibility of getting a reliable individual EEG characterization of deficits of endogenous orienting of spatial attention in right-brain damaged (RBD) patients with left spatial neglect (N+). We used a single-trial topographical analysis (STTA; [39] of individual scalp EEG topographies recorded during leftward and rightward orienting of attention with central cues in RBD patients with and without (N-) neglect and in healthy controls (HC). We found that the STTA successfully decoded EEG signals related to leftward and rightward orienting in five out of the six N+, five out of the six N- patients and in all the six HC. In agreement with findings from conventional average-group studies, successful classifications of EEG signals in N+ were observed during the 400-800 ms period post-cue-onset, which reflects preserved voluntary engagement of attention resources (ADAN component). These results suggest the possibility of acquiring reliable individual EEG profiles of neglect patients.


Asunto(s)
Atención , Trastornos de la Percepción/fisiopatología , Conducta Espacial , Accidente Cerebrovascular/complicaciones , Anciano , Encéfalo/fisiopatología , Electroencefalografía , Femenino , Lateralidad Funcional , Humanos , Masculino , Persona de Mediana Edad , Trastornos de la Percepción/etiología
15.
Brain Commun ; 3(2): fcab111, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34151266

RESUMEN

Right brain-damaged patients with unilateral spatial neglect fail to explore the left side of space. Recent EEG and clinical evidence suggests that neglect patients might suffer deficits in predictive coding, i.e. in identifying and exploiting probabilistic associations among sensory stimuli in the environment. To gain direct insights on this issue, we focussed on the hierarchical components of predictive coding. We recorded EEG responses evoked by central, left-side or right-side tones that were presented at the end of sequences of four central tones. Left-side and right-side deviant tones produce a pre-attentive Mismatch Negativity that reflects a lower-order prediction error for the 'Local' deviation of the tone at the end of the sequence. Higher-order prediction errors for the frequency of these deviations in the acoustic environment, i.e. 'Global' deviation, are marked by the P3 response. We show that when neglect patients are immersed in an acoustic environment characterized by frequent left-side deviant tones, they display no pre-attentive Mismatch Negativity both for left-side deviant tones and infrequent omissions of the last tone, while they have Mismatch Negativity for infrequent right-side deviant tones. In the same condition, neglect patients show no P300 response to 'Global' prediction errors for deviant tones, including those in the non-neglected right-side, and omissions. In contrast to this, when right-side deviant tones are predominant in the acoustic environment, neglect patients have pre-attentive Mismatch Negativity both for right-side deviant tones and infrequent omissions, while they display no Mismatch Negativity for infrequent left-side deviant tones. Most importantly, in the same condition neglect patients show enhanced P300 response to infrequent left-side deviant tones, notwithstanding that these tones evoked no pre-attentive Mismatch Negativity. This latter finding indicates that 'Global' predictions are independent of 'Local' error signals provided by the Mismatch Negativity. These results qualify deficits of predictive coding in the spatial neglect syndrome and show that neglect patients base their predictive behaviour only on statistical regularities that are related to the frequent occurrence of sensory events on the right side of space.

16.
J Neuropsychol ; 14(3): 431-448, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-31617330

RESUMEN

The hypothesis that semantic deficits in dementia may contribute in producing changes in eating preferences has never been experimentally investigated despite this association has been clinically observed. We administered tasks assessing semantic memory and the Appetite and Eating Habits Questionnaire (APEHQ) to 23 patients with dementia (behavioural frontotemporal dementia, primary progressive aphasia, and Alzheimer's disease) and to 21 healthy controls. We used voxel-based morphometry and diffusion tensor imaging to identify regions and white matter tracts of significant atrophy associated with the performance at the semantic tasks and the pathological scores at the APEHQ. We observed that the lower the patients' scores at semantic tasks, the higher their changes in eating habits and preferences. Both semantic disorders and eating alterations correlated with atrophy in the temporal lobes and white matter tracts connecting the temporal lobe with frontal regions such as the arcuate fasciculus, the cingulum, and the inferior longitudinal fasciculus. These results confirm that semantic deficits underlie specific eating alterations in dementia patients.


Asunto(s)
Demencia/psicología , Conducta Alimentaria/psicología , Semántica , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/psicología , Afasia Progresiva Primaria/psicología , Atrofia , Estudios de Casos y Controles , Imagen de Difusión Tensora , Femenino , Lóbulo Frontal/patología , Demencia Frontotemporal/psicología , Humanos , Masculino , Memoria , Vías Nerviosas/patología , Encuestas y Cuestionarios , Lóbulo Temporal/patología , Sustancia Blanca/patología
17.
Behav Res Ther ; 119: 103408, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31176134

RESUMEN

The prefrontal cortex (PFC) plays a central role in food choice, and may be partly dysfunctional in obesity - a condition linked to altered attention and inhibition processes, particularly in response to food-related stimuli. We investigated the role of the PFC in subliminal visual processing and response inhibition to food pictures using anodal, cathodal, or sham transcranial direct current stimulation (tDCS) in a sample of 53 normal weight, overweight, or obese participants. Subliminal processing was measured with a breaking continuous flash suppression task (bCFS), and inhibition with a Go/No-Go task. BMI was included in the analyses as a continuous predictor. Higher BMI was associated with prolonged subliminal processing for both food and nonfood pictures in the bCFS task, and with longer RTs in food Go trials in the Go/No-Go task. Therefore, higher BMI was associated with an attentional bias for food images during supraliminal, but not subliminal visual processing. Moreover, anodal tDCS resulted in shorter detection times in the bCFS task, especially in participants with higher BMI. We conclude that anodal tDCS affects subliminal perception and attentional processes, and speculate that these effects may explain previous reports of reduced craving and food intake after anodal tDCS.


Asunto(s)
Sesgo Atencional/fisiología , Concienciación/fisiología , Inhibición Psicológica , Obesidad/psicología , Sobrepeso/psicología , Corteza Prefrontal/fisiología , Estimulación Subliminal , Percepción Visual/fisiología , Adulto , Índice de Masa Corporal , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Estimulación Luminosa , Desempeño Psicomotor/fisiología , Estimulación Transcraneal de Corriente Directa , Adulto Joven
18.
Sci Rep ; 9(1): 2151, 2019 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-30770857

RESUMEN

The value people attribute to rewards is influenced both by the time and the effort required to obtain them. Impairments in these computations are described in patients with schizophrenia and appear associated with negative symptom severity. This study investigated whether deficits in temporal and effort cost computations can be observed in individuals with subclinical psychotic symptoms (PS) to determine if this dysfunction is already present in a potentially pre-psychotic period. Sixty participants, divided into three groups based on the severity of PS (high, medium and low), performed two temporal discounting tasks with food and money and a concurrent schedule task, in which the effort to obtain food increased over time. We observed that in high PS participants the discounting rate appeared linear and flatter than that exhibited by participants with medium and low PS, especially with food. In the concurrent task, compared to those with low PS, participants with high PS exerted tendentially less effort to obtain snacks only when the required effort was high. Participants exerting less effort in the higher effort condition were those with higher negative symptoms. These results suggest that aberrant temporal and effort cost computations might be present in individuals with subclinical PS and therefore could represent a vulnerability marker for psychosis.


Asunto(s)
Enfermedades Asintomáticas , Toma de Decisiones , Trastornos Psicóticos/diagnóstico , Trastornos Psicóticos/patología , Adulto , Femenino , Humanos , Masculino , Motivación , Pruebas Neuropsicológicas , Recompensa , Adulto Joven
19.
Arch Clin Neuropsychol ; 34(5): 637-647, 2019 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-30272124

RESUMEN

OBJECTIVE: A complex interplay of factors including cognitive, sensory and affective aspects has been associated in a controversial way with anthropometric measures related to body weight. METHODS: Here we propose two studies to investigate whether and how cognitive, olfactory and affective variables resulted associated with body weight during healthy aging. In Study 1, we investigated the cognitive status, the odor identification skills, and the BMI of 209 individuals (50-96 yo). In Study 2 an extensive evaluation of cognitive functions (in particular executive functions and memory), odor threshold, discrimination and identification and affective skills (i.e., depression and anxiety) was performed in a group of 35 healthy, free-living aging individuals (58-85 yo). RESULTS: In Study 1, greater BMI was not associated with performance on the odor identification task but was significantly associated with better cognitive skills. In Study 2, we observed that executive functions seemed to favor a successful managing of body weight, and individuals with greater BMI and waist circumference showed significantly better odor discrimination skills. Finally, lower waist circumference (but not BMI) was found significantly associated with greater levels of anxiety. CONCLUSIONS: These results confirm that cognitive, olfactory and affective factors may influence body weight during healthy aging.


Asunto(s)
Afecto/fisiología , Envejecimiento/psicología , Peso Corporal/fisiología , Cognición/fisiología , Percepción Olfatoria/fisiología , Olfato/fisiología , Anciano , Anciano de 80 o más Años , Envejecimiento/fisiología , Discriminación en Psicología/fisiología , Función Ejecutiva/fisiología , Femenino , Humanos , Masculino , Memoria/fisiología , Persona de Mediana Edad , Pruebas Neuropsicológicas
20.
Sci Rep ; 9(1): 7439, 2019 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-31092880

RESUMEN

Food constitutes a fuel of life for human beings. It is therefore of chief importance that their recognition system readily identifies the most relevant properties of food by drawing on semantic memory. One of the most relevant properties to be considered is the level of processing impressed by humans on food. We hypothesized that recognition of raw food capitalizes on sensory properties and that of transformed food on functional properties, consistently with the hypothesis of a sensory-functional organization of semantic knowledge. To test this hypothesis, patients with Alzheimer's disease, frontotemporal dementia, primary progressive aphasia, and healthy controls performed lexical-semantic tasks with food (raw and transformed) and non-food (living and nonliving) stimuli. Correlations between task performance and local grey matter concentration (VBM) and white matter fractional anisotropy (TBSS) led to two main findings. First, recognition of raw food and living things implicated occipital cortices, typically involved in processing sensory information and, second, recognition of processed food and nonliving things implicated the middle temporal gyrus and surrounding white matter tracts, regions that have been associated with functional properties. In conclusion, the present study confirms and extends the hypothesis of a sensory and a functional organization of semantic knowledge.


Asunto(s)
Alimentos/clasificación , Memoria/fisiología , Reconocimiento en Psicología/fisiología , Anciano , Enfermedad de Alzheimer/fisiopatología , Anisotropía , Afasia Progresiva Primaria/fisiopatología , Encéfalo/fisiopatología , Imagen de Difusión Tensora/métodos , Femenino , Demencia Frontotemporal/fisiopatología , Sustancia Gris/fisiopatología , Humanos , Conocimiento , Masculino , Persona de Mediana Edad , Fibras Nerviosas Mielínicas/fisiología , Vías Nerviosas/fisiopatología , Pruebas Neuropsicológicas , Semántica , Análisis y Desempeño de Tareas , Lóbulo Temporal/fisiopatología , Sustancia Blanca/fisiopatología
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