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We present superconducting properties and vortex states in a thick amorphous MgxB1-x film with x=0.31. Measurements of dc and ac complex resistivities in the mixed state reveal the presence of the vortex-glass transition in three dimensions. Based on the data, we construct the vortex phase diagram in the field–temperature plane. We find that there is the relatively large vortex-liquid phase, which persists down to low temperatures. [Copyright &y& Elsevier]

The superconducting properties in thick amorphous MgxB1−x films with different x (≈0.3–0.4) are presented. The transition temperature Tc changes smoothly as a function of x, exhibiting a peak (Tc=6.1 K) at x≈0.33. This fact, together with the finding that the resistive transition in zero field is sufficiently sharp, demonstrates that our films are highly amorphous and electronic states change systematically as a function of x. On the basis of the ac-complex-resistivity for selected fields, the vortex-solid state is suggested to be the vortex glass. [Copyright &y& Elsevier]

Over a century of scientific work has focused on defining the factors motivating behavioral learning. Observations in animals and humans trained on a wide range of tasks support reinforcement learning (RL) algorithms as accounting for the learning. Still unknown, however, are the signals that drive learning in naive, untrained subjects. Here, we capitalized on a sequential saccade task in which macaque monkeys acquired repetitive scanning sequences without instruction. We found that spike activity in the caudate nucleus after each trial corresponded to an integrated cost-benefit signal that was highly correlated with the degree of naturalistic untutored learning by the monkeys. Across learning, neurons encoding both cost and outcome gradually acquired increasingly sharp phasic trial-end responses that paralleled the development of the habit-like, repetitive saccade sequences. Our findings demonstrate an integrated cost-benefit signal by which RL and its neural correlates could drive naturalistic behaviors in freely behaving primates., (Copyright © 2015 Elsevier Inc. All rights reserved.)

A striking neurochemical form of compartmentalization has been found in the striatum of humans and other species, dividing it into striosomes and matrix. The function of this organization has been unclear, but the anatomical connections of striosomes indicate their relation to emotion-related brain regions, including the medial prefrontal cortex. We capitalized on this fact by combining pathway-specific optogenetics and electrophysiology in behaving rats to search for selective functions of striosomes. We demonstrate that a medial prefronto-striosomal circuit is selectively active in and causally necessary for cost-benefit decision-making under approach-avoidance conflict conditions known to evoke anxiety in humans. We show that this circuit has unique dynamic properties likely reflecting striatal interneuron function. These findings demonstrate that cognitive and emotion-related functions are, like sensory-motor processing, subject to encoding within compartmentally organized representations in the forebrain and suggest that striosome-targeting corticostriatal circuits can underlie neural processing of decisions fundamental for survival., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Background: We have developed a novel head-holding device for behaving non-human primates that affords stability suitable for reliable chronic electrophysiological recording experiments. The device is completely non-invasive, and thus avoids the risk of infection and other complications that can occur with the use of conventional, surgically implanted head-fixation devices., New Method: The device consists of a novel non-invasive head mold and bar clamp holder, and is customized to the shape of each monkey's head. The head-holding device that we introduce, combined with our recording system and reflection-based eye-tracking system, allows for chronic behavioral experiments and single-electrode or multi-electrode recording, as well as manipulation of brain activity., Results and Comparison With Existing Methods: With electrodes implanted chronically in multiple brain regions, we could record neural activity from cortical and subcortical structures with stability equal to that recorded with conventional head-post fixation. Consistent with the non-invasive nature of the device, we could record neural signals for more than two years with a single implant. Importantly, the monkeys were able to hold stable eye fixation positions while held by this device, demonstrating the possibility of analyzing eye movement data with only the gentle restraint imposed by the non-invasive head-holding device., Conclusions: We show that the head-holding device introduced here can be extended to the head holding of smaller animals, and note that it could readily be adapted for magnetic resonance brain imaging over extended periods of time., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Capecitabine is one of the most effective oral chemotherapeutic drugs for advanced or recurrent colorectal cancer and gastric cancer. Capecitabine-containing chemotherapy is recommended as a first-line option for gastrointestinal tract cancer. The incidence of hand-foot syndrome (HFS), an adverse event of chemotherapy with capecitabine, is high. Moreover, once the symptoms of HFS are identified, they can significantly impair the quality of life (QOL) of patients. HFS should be managed by dose interruption and, if necessary, by dose reduction. Pharmacists and oncology nurses play an increasingly important role in the early identification and prevention of HFS through patient education and close clinical assessment. The aim of this study was to evaluate the efficacy of support tools for the early identification, prevention, and management of HFS and to assess the effectiveness of "patient self-check sheets". The patient was detected as having HFS of mild severity and had used a moisturizer at the time of initiation of therapy. Maintaining moisture retention is important in the management of HFS. The ambulatory team plays a key role by using self-check sheets to educate patients on how to recognize HFS, when to interrupt treatment, and how to adjust the dose so as to maintain effective therapy with capecitabine. For the continuation and completion of treatment and for maintaining an improved QOL in the home environment, supportive measures for adverse effects such as HFS and an ambulatory team are indispensable.

The pregenual anterior cingulate cortex (pACC) has been implicated in human anxiety disorders and depression, but the circuit-level mechanisms underlying these disorders are unclear. In healthy individuals, the pACC is involved in cost-benefit evaluation. We developed a macaque version of an approach-avoidance decision task used to evaluate anxiety and depression in humans and, with multi-electrode recording and cortical microstimulation, we probed pACC function as monkeys performed this task. We found that the macaque pACC has an opponent process-like organization of neurons representing motivationally positive and negative subjective value. Spatial distribution of these two neuronal populations overlapped in the pACC, except in one subzone, where neurons with negative coding were more numerous. Notably, microstimulation in this subzone, but not elsewhere in the pACC, increased negative decision-making, and this negative biasing was blocked by anti-anxiety drug treatment. This cortical zone could be critical for regulating negative emotional valence and anxiety in decision-making.

A major goal of neuroscience is to understand the functions of networks of neurons in cognition and behavior. Recent work has focused on implanting arrays of ∼100 immovable electrodes or smaller numbers of individually adjustable electrodes, designed to target a few cortical areas. We have developed a recording system that allows the independent movement of hundreds of electrodes chronically implanted in several cortical and subcortical structures. We have tested this system in macaque monkeys, recording simultaneously from up to 127 electrodes in 14 brain regions for up to one year at a time. A key advantage of the system is that it can be used to sample different combinations of sites over prolonged periods, generating multiple snapshots of network activity from a single implant. Used in conjunction with microstimulation and injection methods, this versatile system represents a powerful tool for studying neural network activity in the primate brain.

A portable system has been designed to enable remote monitoring of autonomic nervous system output in non-human primates for the purpose of studying neural function related to social behavior over extended periods of time in an ambulatory setting. In contrast to prior systems which only measure heart activity, are restricted to a constrained laboratory setting, or require surgical attachment, our system is comprised of a multi-sensor self-contained wearable vest that can easily be transferred from one subject to another. The vest contains a small detachable low-power electronic sensor module for measuring electrodermal activity (EDA), electrocardiography (ECG), 3-axis acceleration, and temperature. The wireless transmission is implemented using a standard Bluetooth protocol and a mobile phone, which enables freedom of movement for the researcher as well as for the test subject. A custom Android software application was created on the mobile phone for viewing and recording live data as well as creating annotations. Data from up to seven monkeys can be recorded simultaneously using the mobile phone, with the option of real-time upload to a remote web server. Sample data are presented from two rhesus macaque monkeys showing stimulus-induced response in the laboratory as well as long-term ambulatory data collected in a large monkey cage. This system enables new possibilities for studying underlying mechanisms between autonomic brain function and social behavior with connection to human research in areas such as autism, substance abuse, and mood disorders.

We propose here that the modular organization of the striatum reflects a context-sensitive modular learning architecture in which clustered striosome-matrisome domains participate in modular reinforcement learning (RL). Based on anatomical and physiological evidence, it has been suggested that the modular organization of the striatum could represent a learning architecture. There is not, however, a coherent view of how such a learning architecture could relate to the organization of striatal outputs into the direct and indirect pathways of the basal ganglia, nor a clear formulation of how such a modular architecture relates to the RL functions attributed to the striatum. Here, we hypothesize that striosome-matrisome modules not only learn to bias behavior toward specific actions, as in standard RL, but also learn to assess their own relevance to the environmental context and modulate their own learning and activity on this basis. We further hypothesize that the contextual relevance or "responsibility" of modules is determined by errors in predictions of environmental features and that such responsibility is assigned by striosomes and conveyed to matrisomes via local circuit interneurons. To examine these hypotheses and to identify the general requirements for realizing this architecture in the nervous system, we developed a simple modular RL model. We then constructed a network model of basal ganglia circuitry that includes these modules and the direct and indirect pathways. Based on simple assumptions, this model suggests that while the direct pathway may promote actions based on striatal action values, the indirect pathway may act as a gating network that facilitates or suppresses behavioral modules on the basis of striatal responsibility signals. Our modeling functionally unites the modular compartmental organization of the striatum with the direct-indirect pathway divisions of the basal ganglia, a step that we suggest will have important clinical implications.

The value of reward obtained with successful behavior is important for guiding purposeful behavior. The lateral prefrontal cortex (LPFC) has been implicated in working memory that guides goal-directed behavior. However, mechanism that integrates the reward value into the working memory for goal-directed behavior is not understood. To help clarify this issue, we examined the effect of reward expectation on the neuronal process in the LPFC associated with memory-based sensorimotor processing. By temporally dissociating visuospatial sensory and saccade-directional motor memories in the LPFC, we here show that reward expectation significantly enhanced the directional selectivity of sensory working memory but did not affect the directional selectivity of motor memory. The enhancement of sensory working memory in the neuronal population was sustained during the delay but extinguished soon after the motor memory appeared. These results suggest that the expectation of high reward value primarily affects the sensory working memory that may be used for behavioral guidance rather than preparation for forthcoming saccades. It thus appears that the LPFC is a neuronal substrate for working memory used to guide a reward-oriented behavior, rather than reflecting an efficient control of motor action in motivated states.

When we react to the outer world, perceived sensory information is frequently memorized over a temporal interval then transformed into a motor command based on a behavioural rule. In this type of memory-based sensorimotor transformation, working memory is considered to play an important role. It has been suggested that the lateral prefrontal cortex is involved in the process of the working memory. However, the neuronal mechanism for guiding a motor command from the working memory has not been established. To examine how visuospatial working memory is linked with a forthcoming saccade direction, we used an antisaccade paradigm for monkeys in which a behavioural rule was presented in the middle of a delay period. In this task, the subjects were required to maintain cue location and to select a response based on a behavioural rule. We found that a subset of mnemonic neurons in the lateral prefrontal cortex changed their representation from cue to saccade direction. Furthermore, the discriminability for saccade direction of these neurons tended to appear soon after the behavioural rule presentation, indicating their significant dependency on the behavioural rule. These results suggest that a subset of mnemonic neurons in the lateral prefrontal cortex change their activity depending on a behavioural rule to guide a prospective motor command.

This article presents a new theoretical framework to consider the dynamics of a stochastic spiking neuron model with general membrane response to input spike. We assume that the input spikes obey an inhomogeneous Poisson process. The stochastic process of the membrane potential then becomes a gaussian process. When a general type of the membrane response is assumed, the stochastic process becomes a Markov-gaussian process. We present a calculation method for the membrane potential density and the firing probability density. Our new formulation is the extension of the existing formulation based on diffusion approximation. Although the single Markov assumption of the diffusion approximation simplifies the stochastic process analysis, the calculation is inaccurate when the stochastic process involves a multiple Markov property. We find that the variation of the shape of the membrane response, which has often been ignored in existing stochastic process studies, significantly affects the firing probability. Our approach can consider the reset effect, which has been difficult to deal with by analysis based on the first passage time density.