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1.
Crit Rev Food Sci Nutr ; : 1-31, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37937848

RESUMEN

Total or partial replacement of traditional durum wheat semolina (DWS) by alternative flours, such as legumes or wholegrain cereals in pasta improves their nutritional quality and can make them interesting vector for fortification. Climate-smart gluten-free (C-GF) flours, such as legumes (bambara groundnut, chickpea, cowpea, faba bean, and pigeon pea), some cereals (amaranth, teff, millet, and sorghum), and tubers (cassava and orange fleshed sweet potato), are of high interest to face ecological transition and develop sustainable food systems. In this review, an overview and a critical analysis of their nutritional potential for pasta production and processing conditions are undertaken. Special emphasis is given to understanding the influence of formulation and processing on techno-functional and nutritional (starch and protein digestibility) properties. Globally C-GF flours improve pasta protein quantity and quality, fibers, and micronutrients contents while keeping a low glycemic index and increasing protein digestibility. However, their use introduces anti-nutritional factors and could lead to the alteration of their techno-functional properties (higher cooking losses, lower firmness, and variability in color in comparison to classical DWS pasta). Nevertheless, these alternative pasta remain more interesting in terms of nutritional and techno-functional quality than traditional maize and rice-based gluten free pasta.

2.
Cereb Cortex ; 25(5): 1319-29, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-24293562

RESUMEN

Macaque electrophysiology has revealed neurons responsive to number in lateral (LIP) and ventral (VIP) intraparietal areas. Recently, fMRI pattern recognition revealed information discriminative of individual numbers in human parietal cortex but without precisely localizing the relevant sites or testing for subregions with different response profiles. Here, we defined the human functional equivalents of LIP (feLIP) and VIP (feVIP) using neurophysiologically motivated localizers. We applied multivariate pattern recognition to investigate whether both regions represent numerical information and whether number codes are position specific or invariant. In a delayed number comparison paradigm with laterally presented numerosities, parietal cortex discriminated between numerosities better than early visual cortex, and discrimination generalized across hemifields in parietal, but not early visual cortex. Activation patterns in the 2 parietal regions of interest did not differ in the coding of position-specific or position-independent number information, but in the expression of a numerical distance effect which was more pronounced in feLIP. Thus, the representation of number in parietal cortex is at least partially position invariant. Both feLIP and feVIP contain information about individual numerosities in humans, but feLIP hosts a coarser representation of numerosity than feVIP, compatible with either broader tuning or a summation code.


Asunto(s)
Imagen por Resonancia Magnética , Matemática , Lóbulo Parietal/fisiología , Corteza Visual/fisiología , Adulto , Mapeo Encefálico/métodos , Femenino , Lateralidad Funcional/fisiología , Humanos , Masculino , Estimulación Luminosa/métodos , Percepción Visual/fisiología , Adulto Joven
3.
Neuroimage ; 51(1): 288-99, 2010 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-20153834

RESUMEN

Spatial Independent Component Analysis (ICA) is an increasingly used data-driven method to analyze functional Magnetic Resonance Imaging (fMRI) data. To date, it has been used to extract sets of mutually correlated brain regions without prior information on the time course of these regions. Some of these sets of regions, interpreted as functional networks, have recently been used to provide markers of brain diseases and open the road to paradigm-free population comparisons. Such group studies raise the question of modeling subject variability within ICA: how can the patterns representative of a group be modeled and estimated via ICA for reliable inter-group comparisons? In this paper, we propose a hierarchical model for patterns in multi-subject fMRI datasets, akin to mixed-effect group models used in linear-model-based analysis. We introduce an estimation procedure, CanICA (Canonical ICA), based on i) probabilistic dimension reduction of the individual data, ii) canonical correlation analysis to identify a data subspace common to the group iii) ICA-based pattern extraction. In addition, we introduce a procedure based on cross-validation to quantify the stability of ICA patterns at the level of the group. We compare our method with state-of-the-art multi-subject fMRI ICA methods and show that the features extracted using our procedure are more reproducible at the group level on two datasets of 12 healthy controls: a resting-state and a functional localizer study.


Asunto(s)
Mapeo Encefálico/métodos , Encéfalo/fisiología , Imagen por Resonancia Magnética/métodos , Modelos Estadísticos , Procesamiento de Señales Asistido por Computador , Algoritmos , Automatización , Calibración , Bases de Datos Factuales , Humanos , Análisis Multivariante , Vías Nerviosas/fisiología , Probabilidad , Reproducibilidad de los Resultados
4.
Science ; 284(5416): 970-4, 1999 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-10320379

RESUMEN

Does the human capacity for mathematical intuition depend on linguistic competence or on visuo-spatial representations? A series of behavioral and brain-imaging experiments provides evidence for both sources. Exact arithmetic is acquired in a language-specific format, transfers poorly to a different language or to novel facts, and recruits networks involved in word-association processes. In contrast, approximate arithmetic shows language independence, relies on a sense of numerical magnitudes, and recruits bilateral areas of the parietal lobes involved in visuo-spatial processing. Mathematical intuition may emerge from the interplay of these brain systems.


Asunto(s)
Lóbulo Frontal/fisiología , Lenguaje , Matemática , Lóbulo Parietal/fisiología , Pensamiento , Adulto , Mapeo Encefálico , Potenciales Evocados , Femenino , Humanos , Intuición , Imagen por Resonancia Magnética , Masculino
5.
Brain Struct Funct ; 221(7): 3361-71, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-26346119

RESUMEN

It is generally accepted in neuroscience that anatomy and function go hand in hand. Accordingly, a local morphological variability could lead to a corresponding functional variability. In this study, we tested this hypothesis by linking the variability of the cortical folding pattern of 252 right-handed subjects to the localization or the pattern of functional activations induced by hand motion or silent reading. Three regions are selected: the central sulcus, the precentral sulcus and the superior temporal sulcus (STS). "Essential morphological variability traits" are identified using a method building upon multidimensional scaling. The link between variability in anatomy and function is confirmed by the perfect match between the central sulcus morphological "hand knob" and the corresponding motor activation: as the location of the hand knob moves more or less dorsally along the central sulcus, the motor hand activation moves accordingly. Furthermore, the size of the left hand activation in the right hemisphere is correlated with the knob location in the central sulcus. A new link between functional and morphological variability is discovered relative to the location of a premotor activation induced by silent reading. While this reading activation is located next to the wall of the central sulcus when the hand knob has a ventral positioning, it is pushed into a deep gyrus interrupting the precentral sulcus when the knob is more dorsal. Finally, it is shown that the size of the reading activation along the STS is larger when the posterior branches are less developed.


Asunto(s)
Mano/fisiología , Actividad Motora , Corteza Motora/anatomía & histología , Corteza Motora/fisiología , Lectura , Lóbulo Temporal/anatomía & histología , Lóbulo Temporal/fisiología , Mapeo Encefálico , Humanos , Imagen por Resonancia Magnética
6.
Neuroreport ; 10(7): 1473-9, 1999 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-10380965

RESUMEN

Cerebral activity during number comparison was studied with functional magnetic resonance imaging using an event-related design. We identified an extended network of task-related areas that showed a phasic activation following each trial, including anterior cingulate, bilateral sensorimotor areas, inferior occipito-temporal cortices, posterior parietal cortices, inferior and dorsolateral prefrontal cortices, and thalami. We then tested which of these areas were affected by number notation, numerical distance and response side, three variables that specifically target processes of visual identification, quantity manipulation and motor response in a serial-stage model of the number comparison task. Our results confirm the role of the right fusiform gyrus in digit identification processes, and of the inferior parietal lobule in the internal manipulation of numerical quantities.


Asunto(s)
Mapeo Encefálico/métodos , Imagen por Resonancia Magnética/métodos , Reconocimiento Visual de Modelos/fisiología , Adulto , Análisis de Varianza , Potenciales Evocados/fisiología , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Valores de Referencia
7.
Physiol Behav ; 72(1-2): 141-6, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11239991

RESUMEN

With the aim of evaluating the sympathetic-adrenal medulla system in subjects practicing transcendental meditation (TM), their plasma catecholamine levels were determined at two different times of day. The study group consisted of 19 subjects who regularly practice either TM or Sidhi-TM technique, with a control group made up of 16 healthy subjects who had not previously used any relaxation technique. Catecholamine plasma levels were determined by high performance liquid chromatography, at 0900 and 2000 h. Morning and evening norepinephrine (NE) levels and morning epinephrine (E) levels were significantly lower in the TM group than in the control subjects (morning NE levels, pg/ml, mean+/-S.E.: TM group 136.6+/-13.0, control 236.8+/-21.0, P=.0001; evening NE levels: TM group 119.7+/-10.8, control 175.6+/-17.4, P=.009; morning E levels, pg/ml: TM group 140.2+/-10.6, control 196.7+/-23.8, P=.019). No differences were recorded for evening E levels and dopamine (DA) levels. No significant differences were found for catecholamine levels measured at different times of day in the TM group, demonstrating a lack of daily hormonal rhythm. Anxiety levels were similar in both groups. Based on the results obtained, it can be considered that the regular practice of TM has a significant effect on the sympathetic-adrenal medulla system. A low hormonal response to daily stress caused by sympathetic tone regulation through regular TM could explain our results, as well as the physiological and other effects related to the field of health described in those who practice meditation.


Asunto(s)
Catecolaminas/sangre , Meditación/psicología , Adolescente , Médula Suprarrenal/fisiología , Adulto , Cromatografía Líquida de Alta Presión , Ritmo Circadiano/fisiología , Dopamina/sangre , Epinefrina/sangre , Femenino , Humanos , Masculino , Norepinefrina/sangre , Sistema Nervioso Simpático/fisiología
9.
Hist Psychiatry ; 3(11): 351-70, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11612882
10.
Cogn Neuropsychol ; 23(8): 1162-73, 2006 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-21049372

RESUMEN

There is a universal and often unconscious tendency to mentally associate the number sequence with a spatial continuum (the mental number line). Here we study one individual who reports a strong and vivid sense of space when processing numbers. For him, the number sequence has a precise spatial form: a curvilinear right-to-left oriented line. We used various tasks to demonstrate that this numerical-spatial association is not a mere figment of his imagination, but a constrained experiential phenomenon consistent across sessions and automatically triggered by the visual presentation of numbers. We also show that this idiosyncratic representation can coexist with another implicit association, the SNARC effect (Spatial-Numerical Association of Response Codes, where small numbers are associated with the left side of space). This effect is present in individuals without explicit number forms and is not affected in the present subject in spite of his reversed subjective representation.

11.
Neuroimage ; 14(5): 1013-26, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11697933

RESUMEN

The time to compare two numbers shows additive effects of number notation and of semantic distance, suggesting that the comparison task can be decomposed into distinct stages of identification and semantic processing. Using event-related fMRI and high-density ERPs, we isolated cerebral areas where activation was influenced by input notation (verbal or Arabic notation). The bilateral extrastriate cortices and a left precentral region were more activated during verbal than during Arabic stimulation, while the right fusiform gyrus and a set of bilateral inferoparietal and frontal regions were more activated during Arabic than during verbal stimulation. We also identified areas that were influenced solely by the semantic content of the stimuli (numerical distance between numbers to be compared) independent of the input notation. Activation tightly correlated with numerical distance was observed mainly in a group of parietal areas distributed bilaterally along the intraparietal sulci and in the precuneus, as well as in the left middle temporal gyrus and posterior cingulate. Our results support the assumption of a central semantic representation of numerical quantity that relies on a common parietal network shared among notations.


Asunto(s)
Atención/fisiología , Imagen por Resonancia Magnética , Lóbulo Parietal/fisiología , Solución de Problemas/fisiología , Semántica , Adulto , Mapeo Encefálico , Dominancia Cerebral/fisiología , Potenciales Evocados/fisiología , Femenino , Giro del Cíngulo/fisiología , Humanos , Masculino , Red Nerviosa/fisiología , Valores de Referencia , Lóbulo Temporal/fisiología
12.
Brain ; 123 ( Pt 11): 2240-55, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11050024

RESUMEN

Neuropsychological studies have revealed different subtypes of dyscalculia, including dissociations between exact calculation and approximation abilities, and an impact of number size on performance. To understand the origins of these effects, we measured cerebral activity with functional MRI at 3 Tesla and event-related potentials while healthy volunteers performed exact and approximate calculation tasks with small and large numbers. Bilateral intraparietal, precentral, dorsolateral and superior prefrontal regions showed greater activation during approximation, while the left inferior prefrontal cortex and the bilateral angular regions were more activated during exact calculation. Increasing number size during exact calculation led to increased activation in the same bilateral intraparietal regions as during approximation, as well the left inferior and superior frontal gyri. Event-related potentials gave access to the temporal dynamics of calculation processes, showing that effects of task and of number size could be found as early as 200-300 ms following problem presentation. Altogether, the results reveal two cerebral networks for number processing. Rote arithmetic operations with small numbers have a greater reliance on left-lateralized regions, presumably encoding numbers in verbal format. Approximation and exact calculation with large numbers, however, put heavier emphasis on the left and right parietal cortices, which may encode numbers in a non-verbal quantity format. Subtypes of dyscalculia can be explained by lesions disproportionately affecting only one of these networks.


Asunto(s)
Corteza Cerebral/patología , Corteza Cerebral/fisiopatología , Trastornos del Conocimiento/fisiopatología , Cognición/fisiología , Red Nerviosa/patología , Red Nerviosa/fisiopatología , Reproducibilidad de los Resultados , Adulto , Mapeo Encefálico , Trastornos del Conocimiento/patología , Potenciales Evocados/fisiología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Matemática , Pruebas Neuropsicológicas , Desempeño Psicomotor/fisiología , Tiempo de Reacción/fisiología , Lectura , Simbolismo
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