RESUMEN
Functional near infrared spectroscopy (fNIRS) is a neuroimaging technique that has grown vigorously in recent years. With noticeable attention, machine learning methods have also been applied to fNIRS. However, the current approach lacks interpretability of the results. In recent years, the utilization and investigation of fNIRS have experienced significant growth and are now being utilized in clinical research. However, the collection of clinical fNIRS data is limited in sample size. Therefore, our aim is to utilize the collected fNIRS data from all channels and achieve interpretable analysis results with minimal human manipulation, channel selection or feature extraction. We developed an fNIRS-based interpretable model and used class-specific gradient information to visualize the biomarkers captured by the model via locating the important region. The accuracy of our model's classification was 6% higher than that of the conventional SVM method under within-subject classification. The model focuses on signals from the left brain in the classification of right-hand finger tapping task, while in the task of classifying left-handed movements, the model relies on signals from the right brain. These results were consistent with current understanding of physiology.Clinical Relevance- The machine learning-based fNIRS model has the potential to be used for the diagnosis and prediction of therapeutic efficacy in clinical settings.
Asunto(s)
Encéfalo , Espectroscopía Infrarroja Corta , Humanos , Espectroscopía Infrarroja Corta/métodos , Encéfalo/diagnóstico por imagen , Redes Neurales de la Computación , Mano , Corteza CerebralRESUMEN
Numerous empirical studies have reported that males and females perform equally well in mathematical achievement. However, still to date, very limited is understood about the brain response profiles that are particularly characteristic of males and females when solving mathematical problems. The present study aimed to tackle this issue by manipulating arithmetic problem size to investigate functional significance using functional magnetic resonance imaging (fMRI) in young adults. Participants were instructed to complete two runs of simple calculation tasks with either large or small problem sizes. Behavioural results suggested that the performance did not differ between females and males. Neuroimaging data revealed that sex/gender-related patterns of problem size effect were found in the brain regions that are conventionally associated with arithmetic, including the left middle frontal gyrus (MFG), left intraparietal sulcus (IPS) and insula. Specifically, females demonstrated substantial brain responses of problem size effect in these regions, whereas males showed marginal effects. Moreover, the machine learning method implemented over the brain signal levels within these regions demonstrated that sex/gender is discriminable. These results showed sex/gender effects in the activating patterns varying as a function of the distinct math problem size, even in a simple calculation task. Accordingly, our findings suggested that females and males use two complementary brain resources to achieve equally successful performance levels and highlight the pivotal role of neuroimaging facilities in uncovering neural mechanisms that may not be behaviourally salient.
Asunto(s)
Mapeo Encefálico , Solución de Problemas , Masculino , Adulto Joven , Humanos , Femenino , Solución de Problemas/fisiología , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Lóbulo Parietal/fisiología , Imagen por Resonancia Magnética/métodosRESUMEN
Over the long run, STEM fields had been perceived as dominant by males, despite that numerous studies have shown that female students do not underperform their male classmates in mathematics and science. In this review, we discuss whether and how sex/gender shows specificity in arithmetic processing using a cognitive neuroscience approach not only to capture contemporary differences in brain and behavior but also to provide exclusive brain bases knowledge that is unseen in behavioral outcomes alone. We begin by summarizing studies that had examined sex differences/similarities in behavioral performance of mathematical learning, with a specific focus on large-scale meta-analytical data. We then discuss how the magnetic resonance imaging (MRI) approach can contribute to understanding neural mechanisms underlying sex-specific effects of mathematical learning by reviewing structural and functional data. Finally, we close this review by proposing potential research issues for further exploration of the sex effect using neuroimaging technology. Through the lens of advancement in the neuroimaging technique, we seek to provide insights into uncovering sex-specific neural mechanisms of learning to inform and achieve genuine gender equality in education.
Asunto(s)
Imagen por Resonancia Magnética , Solución de Problemas , Encéfalo/diagnóstico por imagen , Mapeo Encefálico/métodos , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Matemática , Factores SexualesRESUMEN
Emotional items are often remembered more clearly than neutral items. However, whether stimuli embedded in an emotional context are more resistant to directed forgetting than those presented in a neutral context remains unclear. This question was tested by recording event-related potentials (ERPs) in an item-method directed forgetting paradigm involving neutral words that were embedded in neutral or negative contexts. During the study phase, participants were asked to associate a neutral word with a negative or neutral picture. A remember (R) or forget (F) cue was then designated to indicate whether the word was a to-be-remembered (TBR) or to-be-forgotten (TBF) word. In the test phase, participants were asked to identify all previously presented old words regardless of the R/F cues. The behavioral results indicated a significant interaction between the valence of the encoding contexts and the R/F cues. The hit rate was lower for the TBR words encoded in negative contexts relative to those encoded in neutral contexts. No such valence effect was observed in the hit rates of the TBF words. For the ERP data, the R cues elicited a P3b-like effect that has been linked to the selective rehearsal of the TBR items. This effect was more sustained in the negative encoding context than in the neutral context. The F cues elicited a frontal positivity that has been linked to the active inhibition of the TBF words; however, this positivity was not modulated by the valence of the encoding context. The sustained P3b-like effect for the R cues in the negative encoding context might reflect a compensative encoding for the TBR words caused by the attention-capturing negative contexts. Therefore, we argue that the emotional context affected the selective elaboration of the TBR words; however, we also argue that there was no supportive evidence of an emotional effect on the forgetting of TBF items.
Asunto(s)
Corteza Cerebral/fisiología , Emociones/fisiología , Potenciales Evocados/fisiología , Inhibición Psicológica , Recuerdo Mental/fisiología , Adolescente , Adulto , Señales (Psicología) , Electroencefalografía , Femenino , Humanos , Masculino , Adulto JovenRESUMEN
This study employed transcranial direct current stimulation (tDCS) to examine whether the left posterior parietal cortex (LPPC) is causally involved in episodic memory retrieval. Thirty-six participants were assigned to the anodal or the cathodal stimulation group with the block-randomization method and engaged in three source memory tests on three separate days. During the test phase, the participants received anodal or cathodal stimulation over the LPPC scalp region in one visit, sham over the LPPC in another visit, and anodal or cathodal stimulation over the right primary motor cortex (M1) scalp region in the other visit. The results showed that source memory accuracy, but not old/new recognition performance, decreased significantly when participants in the cathodal group received stimulation over the LPPC scalp region in comparison to the other two stimulation conditions. No such effect was found in the anodal group. These findings provide evidence for the causal relationship between the LPPC and episodic memory retrieval.
Asunto(s)
Memoria Episódica , Recuerdo Mental/fisiología , Lóbulo Parietal/fisiología , Adulto , Femenino , Humanos , Masculino , Reconocimiento en Psicología/fisiología , Estimulación Magnética Transcraneal , Adulto JovenRESUMEN
Overexpression of Aurora kinases is largely observed in many cancers, including hematologic malignancies. In this study, we investigated the effects and molecular mechanisms of Aurora kinase inhibitors in acute lymphoblastic leukemia (ALL). Western blot analysis showed that both Aurora-A and Aurora-B are overexpressed in ALL cell lines and primary ALL cells. Both VE-465 and VX-680 effectively inhibited Aurora kinase activities in nine ALL cell lines, which exhibited different susceptibilities to the inhibitors. Cells sensitive to Aurora kinase inhibitors underwent apoptosis at an IC50 of â¼10-30 nM and displayed a phenotype of Aurora-A inhibition, whereas cells resistant to Aurora kinase inhibitors (with an IC50 more than 10 µM) accumulated polyploidy, which may have resulted from Aurora-B inhibition. Drug susceptibility of ALL cell lines was not correlated with the expression level or activation status of Aurora kinases. Interestingly, RS4;11 and MV4;11 cells, which contain the MLL-AF4 gene, were both sensitive to Aurora kinase-A inhibitors treatment. Complementary DNA (cDNA) microarray analysis suggested that CDKN1A might govern the drug responsiveness of ALL cell lines in a TP53-independent manner. Most importantly, primary ALL cells with MLL-AF4 and CDKN1A expression were sensitive to Aurora kinase inhibitors. Our study suggests CDKN1A could be a potential biomarker in determining the drug responsiveness of Aurora kinase inhibitors in ALL, particularly in MLL-AF4-positive patients.