6 research outputs found
Dynamic reorganization of the cortico-basal ganglia-thalamo-cortical network during task learning
Adaptive behavior is coordinated by neuronal networks that are distributed across multiple brain regions such as in the cortico-basal ganglia-thalamo-cortical (CBGTC) network. Here, we ask how cross-regional interactions within such mesoscale circuits reorganize when an animal learns a new task. We apply multi-fiber photometry to chronically record simultaneous activity in 12 or 48 brain regions of mice trained in a tactile discrimination task. With improving task performance, most regions shift their peak activity from the time of reward-related action to the reward-predicting stimulus. By estimating cross-regional interactions using transfer entropy, we reveal that functional networks encompassing basal ganglia, thalamus, neocortex, and hippocampus grow and stabilize upon learning, especially at stimulus presentation time. The internal globus pallidus, ventromedial thalamus, and several regions in the frontal cortex emerge as salient hub regions. Our results highlight the learning-related dynamic reorganization that brain networks undergo when task-appropriate mesoscale network dynamics are established for goal-oriented behavior
A new introductory quantum mechanics curriculum
The Institute of Physics New Quantum Curriculum consists of freely available
online learning and teaching materials (quantumphysics.iop.org) for a first
course in university quantum mechanics starting from two-level systems. This
approach immediately immerses students in inherently quantum mechanical aspects
by focusing on experiments that have no classical explanation. It allows from
the start a discussion of interpretive aspects of quantum mechanics and quantum
information theory. This article gives an overview of the resources available
at the IOP website. The core text is presented as around 80 articles
co-authored by leading experts that are arranged in themes and can be used
flexibly to provide a range of alternative approaches. Many of the articles
include interactive simulations with accompanying activities and problem sets
that can be explored by students to enhance their understanding. Much of the
linear algebra needed for this approach is part of the resource. Solutions to
activities are available to instructors. The resources can be used in a variety
of ways from supplements to existing courses to a complete programme.Comment: 10 pages, 2 figures, 1 table; submitted to the European Journal of
Physic
Striatum-projecting prefrontal cortex neurons support working memory maintenance
Abstract Neurons in the medial prefrontal cortex (mPFC) are functionally linked to working memory (WM) but how distinct projection pathways contribute to WM remains unclear. Based on optical recordings, optogenetic perturbations, and pharmacological interventions in male mice, we report here that dorsomedial striatum (dmStr)-projecting mPFC neurons are essential for WM maintenance, but not encoding or retrieval, in a T-maze spatial memory task. Fiber photometry of GCaMP6m-labeled mPFCâdmStr neurons revealed strongest activity during the maintenance period, and optogenetic inhibition of these neurons impaired performance only when applied during this period. Conversely, enhancing mPFCâdmStr pathway activityâvia pharmacological suppression of HCN1 or by optogenetic activation during the maintenance periodâalleviated WM impairment induced by NMDA receptor blockade. Moreover, cellular-resolution miniscope imaging revealed that >50% of mPFCâdmStr neurons are active during WM maintenance and that this subpopulation is distinct from neurons active during encoding and retrieval. In all task periods, neuronal sequences were evident. Striatum-projecting mPFC neurons thus critically contribute to spatial WM maintenance