Saccade planning and execution can be affected by a multitude of factors present in a target selection task. Recent studies have shown that the similarity between a target and nearby distractors affects the curvature of saccade trajectories, due to target-distractor competition. To further understand the nature of this competition, we varied the distance between and the similarity of complex target and distractor objects in a delayed match-to-sample task to examine their effects on human saccade trajectories and better understand the underlying neural circuitry. For trials with short saccadic reaction times (SRTs) when target-distractor competition is still active, the distractor is attractive and saccade trajectories are deviated towards the distractor. We found a robust effect of distance consistent with saccade vector averaging, whereas the effect of similarity suggested the existence of an object-based suppressive surround. At longer SRTs there was sufficient time for competition between the objects to...

Gene Expression Omnibus database shows significantly downregulated expression of ubiquitin protein ligase E3 component N-recognin 1 (UBR1) in spinal cord injury (SCI). In this study, we investigated the mechanism of action of UBR1 in SCI. Following the establishment of SCI models in rats and PC12 cells, Basso–Beattie–Bresnahan (BBB) score and hematoxylin-eosin (H&E) and Nissl staining were used to evaluate SCI. The localization of NeuN/LC3 and the expression of LC3II/I, Beclin-1, and p62 were detected to assess autophagy. The expression of Bax, Bcl-2, and cleaved caspase-3 was detected and TdT-mediated dUTP-biotin nick end-labeling staining was employed to determine the changes in apoptosis. The N(6)-methyladenosine (m6A) modification level of UBR1 was analyzed by methylated RNA immunoprecipitation, and the binding of METTL14 and UBR1 mRNA was analyzed by photoactivatable ribonucleoside-enhanced crosslinking and immunoprecipitation. UBR1 was poorly expressed, and METTL14 was highly expressed in rat and cel...

Despite the significant health consequences of anxiety, the neural basis of regulation for personal anxious events is not well understood. We examined brain activity and functional connectivity during cognitive emotion regulation strategies (reappraisal and acceptance) for personal anxious events. Functional MRI (fMRI) data were obtained while 35 college students were thinking about (the control condition), reappraising, or accepting their own anxiety-provoking situations. Although reappraisal and acceptance decreased anxiety, no statistically significant differences were observed in the brain activation levels between cognitive emotion regulation strategies and the control condition. However, acceptance decreased activation in the posterior cingulate cortex and precuneus more than reappraisal. Moreover, functional connectivity with the amygdala and ventral anterior insula distinguished the emotion regulation strategies for anxiety. Reappraisal showed stronger negative functional connectivity with the amyg...

The imagination of tactile stimulation has been shown to activate primary somatosensory cortex (S1) with a somatotopic specificity akin to that seen during the perception of tactile stimuli. Using fMRI and multivariate pattern analysis, we investigate whether this recruitment of sensory regions also reflects content-specific activation (i.e., whether the activation in S1 is specific to the mental content participants imagined). To this end, healthy volunteers ( n  = 21) either perceived or imagined three types of vibrotactile stimuli (mental content) while fMRI data were acquired. Independent of the content, during tactile mental imagery we found activation of frontoparietal regions, supplemented with activation in the contralateral BA2 subregion of S1, replicating previous reports. While the imagery of the three different stimuli did not reveal univariate activation differences, using multivariate pattern classification, we were able to decode the imagined stimulus type from BA2. Moreover, cross-classific...

Animals are capable of representing different scale spaces from smaller to larger ones. However, most laboratory animals live their life in a narrow range of scale spaces like homecages and experimental setups, making it hard to extrapolate the spatial representation and learning process in large scale spaces from those in conventional scale spaces. Here, we developed a 3-m diameter Barnes maze (BM3), then explored whether spatial learning in the Barnes maze (BM) is calibrated by scale spaces. Spatial learning in the BM3 was successfully established with a lower learning rate than that in a conventional 1-m diameter Barnes maze (BM1). Specifically, analysis of exploration strategies revealed that the mice in the BM3 persistently searched certain places throughout the learning, while such places were rapidly decreased in the BM1. These results suggest dedicated exploration strategies requiring more trial-and-errors and computational resources in the BM3 than in the BM1, leading to a divergence of spatial le...

The cochlea hair cells transform mechanic sounds to neural signals with a remarkable sensitivity and resolution. This is achieved via the precisely sculpted mechanotransduction apparatus of the hair cells and the supporting structure of the cochlea. The shaping of the mechanotransduction apparatus, the staircased stereocilia bundles on the apical surface of the hair cells, requires an intricate regulatory network including planar cell polarity (PCP) and primary cilia genes in orienting stereocilia bundles and building molecular machinery of the apical protrusions. The mechanism linking these regulatory components is unknown. Here, we show that a small GTPase known for its role in protein trafficking, Rab11a, is required for ciliogenesis in hair cells during development in mice. In addition, in the absence of Rab11a, stereocilia bundles lost their cohesion and integrity, and mice are deaf. These data indicate an essential role of protein trafficking in the formation of hair cell mechanotransduction apparatu...

Nicotine is an addictive drug whose popularity has recently increased, particularly among adolescents, because of the availability of electronic nicotine devices (i.e., “vaping”) and nicotine e-liquids containing additives with rich chemosensory properties. Some efforts to understand the role of these additives in nicotine reward suggest that they increase nicotine reward and reinforcement, but the sensory contributions of additives, especially in their vapor forms, are largely untested. Here, to better understand how a fruit-flavored (i.e., strawberry) additive influences nicotine reward and aversion, we used a conditioned place preference (CPP) procedure in which nicotine and a strawberry additive were delivered as a vapor to male and female adolescent mice. We found that nicotine vapor alone can lead to a dose-dependent CPP when using a biased design. The strawberry additive did not produce CPP on its own, and we did not observe an effect of the strawberry additive on nicotine vapor-induced reward. Neve...

While animal and human decision strategies are typically explained by model-free and model-based reinforcement learning (RL), their choice sequences often follow simple procedures based on working memory (WM) of past actions and rewards. Here, we address how working memory-based choice strategies, such as win-stay-lose-switch (WSLS), are represented in the prefrontal and motor cortico-basal ganglia loops by simultaneous recording of neuronal activities in the dorsomedial striatum (DMS), the dorsolateral striatum (DLS), the medial prefrontal cortex (mPFC), and the primary motor cortex (M1). In order to compare neuronal representations when rats employ working memory-based strategies, we developed a new task paradigm, a continuous/intermittent choice task, consisting of choice and no-choice trials. While the continuous condition (CC) consisted of only choice trials, in the intermittent condition (IC), a no-choice trial was inserted after each choice trial to disrupt working memory of the previous choice and ...

The nucleus accumbens (NAc) is a critical component of a limbic basal ganglia circuit that is thought to play an important role in decision-making and the processing of rewarding stimuli. As part of this circuit, dopamine D1 receptor-expressing medium spiny neurons (D1-MSNs) of the NAc core are known to send a major projection to the substantia nigra pars reticulata (SNr). However, the functional role of this SNr-projecting NAc D1-MSN (NAcD1-MSN–SNr) pathway is still largely uncharacterized. Moreover, as the SNr is thought to belong to both limbic and motor information-processing basal ganglia loops, it is possible that the NAcD1-MSN–SNr pathway may be able to influence both limbic and motor functions. In this study, we investigated the effect of optogenetic manipulation of the NAcD1-MSN–SNr pathway on reward-learning and locomotor behavior in male mice. Stimulation of the axon terminals of NAc core D1-MSNs in the SNr induced a preference for a laser-paired location, self-stimulation via a laser-paired lev...

Approximately 10% of births are preterm [PTB; <37 weeks gestational age (GA)], which confers risk for cognitive, behavioral, and mental health challenges. Using the large and relatively diverse (i.e., designed to reflect sociodemographic variation in the United States population) Adolescent Brain Cognitive Development Study (ABCD Study), we characterized the impact of PTB on brain structure in middle-late childhood (9–10 years). The ABCD sample covers the GA spectrum, and the large sample size (∼11,500) permits consideration of how associations between PTB and brain structure are impacted by GA, sex, birthweight, and analytic choices such as controlling for total brain size. We found a pattern of relative cortical thinning in temporoparietal and dorsal prefrontal regions and thickening of medial prefrontal and occipital regions in PTB compared with children born full term (≥37 weeks GA). This pattern was apparent when controlling for mean thickness and when considering moderate (>32 and <37 weeks GA) and v...