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The information stored in working memory can be transformed into the system of long-term memory due to the long-term potential (LTP) mechanism. The θ-burst stimulation (TBS) can be used as an LTP induction protocol in some experiments, but it has not been used in the models related to memory. In this work, an improved Camperi-Wang (C-W) model with the Ca subsystem-induced bistability is adopted, and the TBS is simulated to be the initial stimuli of this model. With the evolution of the effects of the stimuli properties such as the cycle, the amplitude, and the duty ration on the memory mechanism of this model, the TBS can be adopted to activate working memory models and produce long-term memory. The study helps to propose the relationship between working memory and long-term memory, which lays a theoretical basis for the study of the neural mechanism of long-term memory. [ABSTRACT FROM AUTHOR]

The mechanisms of task-positive and task-negative activations are basic elements for exploring cognitive functions, impairment of which would trigger degenerative neurological diseases. Our research group combined the default mode network (DMN) with the working memory model, chosen as the task positive network (TPN), to carry out computational simulation under various stimulus conditions. The paper has demonstrated the following results: 1) task-positive (TPN) and task-negative networks (TNN) represented antagonistic neural activities; 2) the degree of attenuation in TNN was enhanced with increasing stimulus directions on the working memory; 3) neural activities in TNN decreased as long as that in working memory-related brain regions increase; 4) the more difficult the working memory task was, the more rapidly neural activities in TNN attenuated. Since the task-negative activation was the main characteristic of DMN, mutual inhibition between DMN and TPN was the key of the antagonism between the two networks with different properties. [ABSTRACT FROM AUTHOR]