A Terrified Sound Stress Impairs Learning And Memory Ability of Adult Female

Stress, as an important environmental factor of mental health, cannot be ignored. The great physiological difference between males and females implies that the effects of stress may differ by gender. However, few studies have focused on the effects of stress on females. This study investigated the effects of a terrified sound stress on adult female mice.Methods: 32 adults female C57BL/6 mice were randomly divided into control group (n=16) and stress group (n=16). Sucrose preference test and open field test (OFT) were carried out to evaluate the anxiety and depression of mice. Spatial learning and memory ability were measured by Morris Water maze test (MWM). Endocrine hormones were determined by enzyme-linked immunosorbent assay (ELISA). Serum differential proteins were screened by mass spectrometry (MS). Results: Compared with control group, the sucrose preference of stress group was decreased; in MWM, the escape latency of the stress group was significantly prolonged (P<0.05), and the total swimming distance was significantly increased (P<0.05).Serum T (P<0.05), GnRH (P<0.05), FSH and LH levels decreased; thirty six differential peaks were found by MS, eight of them had high multiples of difference (> 1.2 or <0.8). Conclusion: terrified sound stress impairs spatial learning ability and mental health of adult female mice.

Social dominance has limited effects on spatial cognition in a wild food-caching bird

Social dominance has long been used as a model to investigate social stress. However, many studies using such comparisons have been performed in captive environments. These environments may produce unnaturally high antagonistic interactions, exaggerating the stress of social subordination and any associated adverse consequences. One such adverse effect concerns impaired cognitive ability, often thought to be associated with social subordination. Here, we tested whether social dominance rank is associated with differences in spatial learning and memory, and in reversal spatial learning (flexibility) abilities in wild food-caching mountain chickadees at different montane elevations. Higher dominance rank was associated with higher spatial cognitive flexibility in harsh environments at higher elevations, but not at lower, milder elevations. By contrast, there were no consistent differences in spatial learning and memory ability associated with dominance rank. Our results suggest that spatial learning and memory ability in specialized food-caching species is a stable trait resilient to social influences. Spatial cognitive flexibility, on the other hand, appears to be more sensitive to environmental influences, including social dominance. These findings contradict those from laboratory studies and suggest that it is critical to investigate the biological consequences of social dominance under natural conditions.

Memory perfectionism is associated with persistent memory complaints after concussion

Objective: The etiology of persistent memory complaints after concussion is poorly understood. Memory perfectionism (highly valuing memory ability and intolerance of minor memory lapses) may help explain why some people report persistent subjective memory problems in the absence of corresponding objective memory impairment. The present study investigated the relationship between memory perfectionism and persistent memory complaints after concussion. Methods: Adults (N=77; 61% women) with persistent symptoms following concussion were recruited from outpatient specialty clinics. Participants completed the National Institutes of Health Toolbox Cognition Battery, Test of Memory Malingering-Trial 1, and questionnaires measuring memory perfectionism (Memory in Adulthood-Achievement subscale), forgetfulness and other post-concussion symptoms (Rivermead Postconcussion Symptoms Questionnaire; RPQ), and depression (Patient Health Questionnaire-2) at M=17.8 weeks post-injury. Patients with vs. without severe memory complaints (based on the RPQ) were compared. Results: Memory perfectionism was associated with severe memory complaint, after controlling for objective memory ability, overall cognitive ability, and depression (95% confidence interval for odds ratio = 1.11 to 1.40). Sensitivity analyses showed that this relationship did not depend on use of specific objective memory tests nor on inclusion of participants who failed performance validity testing. In a control comparison to test the specificity of identified relationships, memory perfectionism was not associated with severe fatigue (95% confidence interval for odds ratio = 0.91 to 1.07). Discussion: Memory perfectionism may predispose people to experience persistent memory symptoms and/or contribute to their perpetuation after concussion, with potential relevance to the spectrum of functional cognitive disorders more broadly.

SS-RNN: A Strengthened Skip Algorithm for Data Classification Based on Recurrent Neural Networks

Recurrent neural networks are widely used in time series prediction and classification. However, they have problems such as insufficient memory ability and difficulty in gradient back propagation. To solve these problems, this paper proposes a new algorithm called SS-RNN, which directly uses multiple historical information to predict the current time information. It can enhance the long-term memory ability. At the same time, for the time direction, it can improve the correlation of states at different moments. To include the historical information, we design two different processing methods for the SS-RNN in continuous and discontinuous ways, respectively. For each method, there are two ways for historical information addition: 1) direct addition and 2) adding weight weighting and function mapping to activation function. It provides six pathways so as to fully and deeply explore the effect and influence of historical information on the RNNs. By comparing the average accuracy of real datasets with long short-term memory, Bi-LSTM, gated recurrent units, and MCNN and calculating the main indexes (Accuracy, Precision, Recall, and F1-score), it can be observed that our method can improve the average accuracy and optimize the structure of the recurrent neural network and effectively solve the problems of exploding and vanishing gradients.

Insulin-like growth factor reduced against decabromodiphenyl ether-209–induced neurodevelopmental toxicity in vivo and in vitro

Objective How to reduce the neurodevelopmental toxicity of decabromodiphenyl ether (PBDE-209) remains unclear. This study investigated neurodevelopmental toxicity of PBDE-209 and the protective effects of insulin-like growth factor-1 (IGF-1) Methods Pregnant Sprague–Dawley rats were treated with PBDE-209 and IGF-1, and the offspring were subjected to the Morris Water Maze test. Hippocampal neurons were cultured with PBDE-209 and IGF-1 or the PI3K inhibitor or MEK inhibitor for cell viability, apoptosis, immunofluorescence, and Western blot assays. Results Prenatal PBDE-209 exposure impaired the learning and memory ability of rats by delaying the mean latency to the platform compared, whereas prenatal treatment with IGF-1 treatment improved the learning and memory ability. In vitro, treatment of primary cultured hippocampal neural stem cells (H-NSCs) with PBDE-209 reduced cell proliferation and differentiation, but induced apoptosis. In contrast, IGF-1 treatment antagonized the cytotoxic effects of PBDE-209 in H-NSCs in vitro. At the gene level, IGF-1 inhibition of PBDE-209–induced cell cytotoxicity was through the activation of the PI3K/AKT and MEK/ERK signaling pathways in vitro because the effect of IGF-1 was blocked by the AKT inhibitor LY294002 and the ERK1/2 inhibitor PD98059. Conclusion Prenatal PBDE-209 exposure impaired the learning and memory ability of rats, whereas IGF-1 treatment was able to inhibit the neurodevelopmental toxicity of PBDE-209 by activation of the PI3K/AKT and ERK1/2 cell pathways.

Contributions of declarative memory and prior knowledge to incidental L2 vocabulary learning

The bulk of second language (L2) vocabulary learning happens incidentally through reading (Rott, 2007; Webb, 2008), but individual differences, such as prior knowledge, modulate the efficacy of such incidental learning. One individual difference that is strongly predicted to play a role in L2 vocabulary is declarative memory ability; however, links between these two abilities have not been explored (Hamrick, Lum, & Ullman, 2018). This study considered declarative memory in conjunction with varying degrees of prior knowledge, since declarative memory may serve a compensatory function (Ullman & Pullman, 2015). L2 Spanish learners completed measures of prior Spanish vocabulary knowledge, declarative memory ability, and incidental L2 vocabulary learning. The results suggest that better declarative memory predicts better immediate learning in general and better vocabulary retention two days later, but only for those with more prior knowledge, consistent with the Matthew Effect previously reported in the literature (Stanovich, 1986).