ERK1/2 activation is necessary for BDNF to increase dendritic spine density in hippocampal CA1 pyramidal neurons

Brain-derived neurotrophic factor (BDNF) is a potent modulator of synaptic transmission and plasticity in the CNS, acting both pre- and postsynaptically. We demonstrated recently that BDNF/TrkB signaling increases dendritic spine density in hippocampal CA1 pyramidal neurons. Here, we tested whether activation of the prominent ERK (MAPK) signaling pathway was responsible for BDNF's effects on spine growth. Slice cultures were transfected with enhanced yellow fluorescent protein (eYFP) by particle-mediated gene transfer, and CA1 pyramidal neurons were imaged by laser-scanning confocal microscopy. We confirmed that BDNF (24 h) increases spine density in apical dendrites of CA1 neurons. The MEK (ERK kinase) inhibitors PD98059 and U0126 completely prevented the increase in spine density induced by BDNF, without having an effect on spine density by themselves. In contrast to its actions on cortical pyramidal neurons, BDNF had minor and rather localized effects on dendritic complexity in hippocampal pyramidal neurons, increasing the total length, but not the branching of apical dendrites within CA1 stratum radiatum, without affecting basal dendrites in stratum oriens. Our results support the hypothesis that the ERK-signaling pathway not only mediates long-term synaptic plasticity and hippocampal-dependent learning, but it is also involved in the structural remodeling of excitatory spine synapses triggered by neurotrophins.     

Simultaneous masking in a dichotic emotion detection task

The present study investigated the possible role of ceiling effects in producing laterality effects of small magnitude in dichotic emotion detection. Twenty two right-handed undergraduate students participated in the present experiment. They were required to detect the presence of a target emotion in the expressions tones of happiness, sadness, anger, and neutrality presented dichotically. Stimuli were adjusted to 70 dB and occurred simultaneously with a white noise mask that had an intensity of 65, 70, 80, or 85 dB. Results showed a left ear advantage (LEA) for the 65 dB mask and a right ear advantage for the 85 dB mask, but only after two testing sessions. The possible existence of a generalized right ear bias that might affect the observed LEA for non-verbal tasks is discussed. Alternative explanations and limitations of the present experiment are also presented.     

Concave utility,transaction costs,and risk in measuring discounting of delayed rewards

Research has consistently found that the decline in the present values of delayed rewards as delay increases is better fit by hyperbolic than by exponential delay-discounting functions. However, concave utility, transaction costs, and risk each could produce hyperbolic-looking data, even when the underlying discounting function is exponential. In Experiments 1 (N = 45) and 2 (N = 103), participants placed bids indicating their present values of real future monetary rewards in computer-based 2nd-price auctions. Both experiments suggest that utility is not sufficiently concave to account for the superior fit of hyperbolic functions. Experiment 2 provided no evidence that the effects of transaction costs and risk are large enough to account for the superior fit of hyperbolic functions.     

COVID-19 Vaccination Acceptance: A Case of Interplay Between Political and Health Dimensions

Vaccines are essential for the eradication of diseases. Yet for many reasons, individuals do not embrace them completely. In the COVID-19 pandemic and with the possibility of the Brazilian population's immunization against the disease, both political and health-related dimensions might have had a role in individual COVID-19 vaccination acceptance. In two studies (n = 974), we tested the hypothesis that participants' vaccination acceptance is related to their past vote in the 2018 Brazilian presidential election (being or not being a Jair Bolsonaro voter) and their different levels of perceived vulnerability to disease (PVD). We further tested whether Bolsonaro's opposition or ambiguous messages towards vaccination (vs. control) increased vaccination rejection among those who have (vs. have not) voted for him and who are low (vs. high) in PVD. Results show that Bolsonaro (vs. non-Bolsonaro) voters accepted less vaccination, with higher rejection rates when participants expressed low (vs. high) PVD. Also, when primed either with Bolsonaro's opposed or ambiguous messages towards COVID-19 vaccination, such participants accepted less vaccines (vs. participants primed with neutral information). These findings are the first to show that the COVID-19 vaccine acceptance is related to their past vote and leadership influence but also different levels of perceived vulnerability to disease.     

Evaluation of the 14-h together relationship and financial education program for couples

A 14-h version of TOGETHER, a relationship and financial education program for couples (Author, 2015), was evaluated by comparing pre- and post-intervention changes in psychological distress, relationship functioning, and financial management in couples that participated in this shorter 14-h workshop (14HW) version, in the original 20-h workshop (20HW) version, or in a control group that received no intervention. The total sample included 649 community couples (14HW group: 320; 20HW group:182; control group: 147) recruited from the Washington, DC, metropolitan area. Self-report data were analyzed through dyadic multilevel models to test mean differences within each group (control, 14HW, and 20HW) and across groups from pre-intervention to post-intervention controlling for demographic differences and baseline measurement of variables. Compared to the 20HW version, the 14HW format had lower attrition and greater participation. In addition, improvements in positive conflict management, relationship quality and satisfaction, and commitment, and reductions in negative conflict management and difficulties paying bills were not significantly different from the 20HW group, but they were significantly different from the control group. Participants reported high levels of program satisfaction. Limitations and programmatic implications, as well as the need for further evaluations of the 14HW version, are discussed.     

VALUES MOTHERS HOLD FOR HANDICAPPED AND NONHANDICAPPED PRESCHOOL CHILDREN IN JAPAN,PUERTO RICO,AND THE UNITED STATES MAINLAND*

This study examines the values held by mothers in Japan, Puerto Rico and the U.S. Mainland for their handicapped and nonhandicapped preschoolers in the contexts of home and school. In order to study values, mothers from the three cultures were asked to rank twelve value items relating to four value areas: physical, intrapersonal, interpersonal, and sociocultural. The value rankings were different in the three cultures and depended upon the home and school contexts. The presence of a diagnosed orthopedic and/or neurological impairment in the child had no overall effect on value ratings but did interact with culture and context to influence mothers' values.     

Does preference rank predict substitution for the reinforcer for problem behavior? a behavioral economic analysis

Predictions made under low response requirements inherent in most preference assessments (PAs) do not guarantee the utility of stimuli in treatments. We examined whether PA rank would predict how well stimuli supported compliance for children with escape‐maintained problem behavior by examining the relation between PA rank and demand elasticity across five fixed‐ratio values. Three patterns were observed: All stimuli were selected equally across values, higher ranked stimuli were selected more at higher values, and something other than the highest ranked stimulus was selected more at higher values (i.e., mixed correspondence).     

The comparative psychology of same-different judgments by humans (Homo sapiens) and monkeys (Macaca mulatta)

The authors compared the performance of humans and monkeys in a Same-Different task. They evaluated the hypothesis that for humans the Same-Different concept is qualitative, categorical, and rule-based, so that humans distinguish 0-disparity pairs (i.e., same) from pairs with any discernible disparity (i.e., different); whereas for monkeys the Same-Different concept is quantitative, continuous, and similarity-based, so that monkeys distinguish small-disparity pairs (i.e., similar) from pairs with a large disparity (i.e., dissimilar). The results supported the hypothesis. Monkeys, more than humans, showed a gradual transition from same to different categories and an inclusive criterion for responding Same. The results have implications for comparing Same-Different performances across species--different species may not always construe or perform even identical tasks in the same way. In particular, humans may especially apply qualitative, rule-based frameworks to cognitive tasks like Same-Different.     

Paradoxical sleep deprivation impairs acquisition, consolidation, and retrieval of a discriminative avoidance task in rats

The aim of the present study was to investigate the effects of paradoxical sleep deprivation (PSD) for 96 h on the learning/memory processes in rats submitted to the plus-maze discriminative avoidance task (PM-DAT), which simultaneously evaluates learning, memory, anxiety and motor function. Four experiments were performed in which rats were submitted to: (1) post-training and pre-test PSD; (2) post-training or pre-test PSD; (3) pre-training PSD or pre-training paradoxical sleep (PS) rebound (24 h) and (4) pre-test PSD rebound. Concerning Experiment I, post-training and pre-test PSD induced memory deficits, an anxiolytic-like behavior and an increase in locomotor activity. In Experiment II, both post-training PS-deprived and pre-test PS-deprived groups showed memory deficits per se. However, only the pre-test PS-deprived animals presented anxiolytic-like behavior and increased locomotor activity. In Experiment III, pre-training PS-deprived rats showed learning and memory deficits, anxiolytic-like behavior and increased locomotor activity. A 24h-sleep recovery period after the PSD abolished the learning and memory deficits but not anxiety and locomotor alterations. Finally, sleep rebound did not modify acquisition (Experiment III) and retrieval (Experiment IV). This study strengthened the critical role of paradoxical sleep (but not sleep rebound) in all the phases of learning and memory formation. In addition, it suggests that PSD effects on acquisition and consolidation do not seem to be related to other behavioral alterations induced by this procedure.