Min Xu,Daniel Baldauf,Chun Qi Chang,Robert Desimone,Li Hai Tan
A large body of previous neuroimaging studies suggests that multiple languages are processed and organized in a single neuroanatomical system in the bilingual brain, although differential activation may be seen in some studies because of different proficiency levels and/or age of acquisition of the two languages. However, one important possibility is that the two languages may involve interleaved but functionally independent neural populations within a given cortical region, and thus, distinct patterns of neural computations may be pivotal for the processing of the two languages. Using functional magnetic resonance imaging (fMRI) and multivariate pattern analyses, we tested this possibility in Chinese-English bilinguals when they performed an implicit reading task. We found a broad network of regions wherein the two languages evoked different patterns of activity, with only partially overlapping patterns of voxels in a given region. These regions, including the middle occipital cortices, fusiform gyri, and lateral temporal, temporoparietal, and prefrontal cortices, are associated with multiple aspects of language processing. The results suggest the functional independence of neural computations underlying the representations of different languages in bilinguals.
The coexistence and interaction of excitatory and inhibitory neurotransmitters at biological synapses enable bilingual communication, serving as a physiological foundation for organism adaptation, internal stability, and regulation of behavior and emotions in mammals. Neuromorphic electronics are expected to emulate the bilingual functions of the biological nervous system for artificial neurorobotics and neurorehabilitation. Here, we have proposed a bilingual bidirectional artificial neuristor array, which utilizes ion migration and electrostatic coupling properties between intrinsically stretchable and self-healing poly(urea-urethane) elastomer and carbon nanotube electrodes, realized by van der Waals integration. The neuristor exhibits depression or potentiation behaviors in response to the same stimulus in different operational phases and achieves a four-quadrant information-processing capability. These properties make it possible to simulate complex neuromorphic processes, which involve bilingual bidirectional responses, such as withdrawal or addiction responses, and array-based automated refresh. Furthermore, the neuristor array is a self-healing neuromorphic electronic device that can function effectively even under 50% mechanical strain and can recover operation voluntarily within 2 h after experiencing mechanical injury. Additionally, the bilingual bidirectional stretchable self-healing neuristor can emulate coordinated neural signal transmission from the motor cortex to muscles and integrate proprioception through strain modulation, similar to the biological muscle spindle. The properties, structure, operation mechanisms, and neurologically integrated functions of the proposed neuristor signify an advancement in neuromorphic electronics for next-generation neurorehabilitation and neurorobotics.
Tao Cheng,Peifen Lu,Yixi Dong,Jiabao Yu,Gang Wang,Jianwei Jiao,Peng Miao,Jin Jiao
Herein, a sequentially responsive peptide DNA bilingual nanobiosensor is developed, which allows integrated quantification of amyloid signaling pathway. In this system, upstream beta-site amyloid precursor protein-cleaving enzyme 1 (BACE1) protease and downstream Aβ oligomer (AβO) are designed as two inputs for the AND DNA logic gate. In the existence of both inputs, peptide substrate with aptamer can be sequentially cleaved, reporting electrochemical and fluorescence dual-mode outputs. In comparison with conventional single protease activity assay based on peptide nanotechnology, this strategy permits accurate diagnosis of Alzheimer's disease (AD) from normal subjects. More importantly, it can achieve distinguished diagnosis between AD and type 2 diabetes mellitus patients. This bilingual nanobiosensor is successfully applied to detect BACE1 (1–100 U mL −1 ) and AβO (5–1000 pg mL −1 ) with limit of detections as low as 0.10 U mL −1 and 0.76 pg mL −1 , respectively. Furthermore, this strategy inspires advanced nanobiosensors to target the activation of other signaling pathways, which are potential tools for future biology and medicine investigation.