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A feature issue is being presented by a team of guest editors containing papers based on contributed submissions including studies presented at Optics and the Brain, held April 24-27, 2023 as part of Optica Biophotonics Congress: Optics in the Life Sciences, in Vancouver, Canada.

Vagus nerve stimulation has shown many benefits for disease therapies but current approaches involve imprecise electrical stimulation that gives rise to off-target effects, while the functionally relevant pathways remain poorly understood. One method to overcome these limitations is the use of optogenetic techniques, which facilitate targeted neural communication with light-sensitive actuators (opsins) and can be targeted to organs of interest based on the location of viral delivery. Here, we tested whether retrograde adeno-associated virus (rAAV2-retro) injected in the heart can be used to selectively express opsins in vagus nerve fibers controlling cardiac function. Furthermore, we investigated whether perturbations in cardiac function could be achieved with photostimulation at the cervical vagus nerve. Viral injection in the heart resulted in robust, primarily afferent, opsin reporter expression in the vagus nerve, nodose ganglion, and brainstem. Photostimulation using both one-photon stimulation and two-photon holography with a GRIN-lens incorporated nerve cuff, was tested on the pilot-cohort of injected mice. Changes in heart rate, surface electrocardiogram, and respiratory responses were observed in response to both one- and two-photon photostimulation. The results demonstrate feasibility of retrograde labeling for organ targeted optical neuromodulation.

A Culture of Hope provides a blueprint for schools wanting to meet the social/emotional needs of youth at risk. In working with staff to develop cultures of hope, the influence of implicit biases and prejudices about people who are living in poverty must be addressed. This essay introduces information and research about implicit biases, illustrates the impact of implicit biases on teaching and learning, and shares strategies for raising awareness about implicit biases against poverty in order to build staff consensus around core beliefs and values.

Significance: Stimulated emission depletion (STED) is a powerful super-resolution microscopy technique that can be used for imaging live cells. However, the high STED laser powers can cause significant photobleaching and sample damage in sensitive biological samples. The dynamic intensity minimum (DyMIN) technique turns on the STED laser only in regions of the sample where there is fluorescence signal, thus saving significant sample photobleaching. The reduction in photobleaching allows higher resolution images to be obtained and longer time-lapse imaging of live samples. A stand-alone module to perform DyMIN is not available commercially. Aim: In this work, we developed an open-source design to implement three-step DyMIN on a STED microscope and demonstrated reduced photobleaching for timelapse imaging of beads, cells, and tissue. Approach: The DyMIN system uses a fast multiplexer circuit and inexpensive field-programmable gate array controlled by Labview software that operates as a stand-alone module for a STED microscope. All software and circuit diagrams are freely available. Results: We compared time-lapse images of bead samples using our custom DyMIN system to conventional STED and recorded a ~46% higher signal when using DyMIN after a 50-image sequence. We further demonstrated the DyMIN system for time-lapse STED imaging of live cells and brain tissue slices. Conclusions: Our open-source DyMIN system is an inexpensive add-on to a conventional STED microscope that can reduce photobleaching. The system can significantly improve signal to noise for dynamic time-lapse STED imaging of live samples. [ABSTRACT FROM AUTHOR]

The article discusses the development and dissemination of open-source neurophotonic tools for neuroscience research. It highlights the importance of accessibility for technology adoption in neurobiology and showcases examples of successful open-source tools like the UCLA Miniscope Project. The document also includes papers on widefield imaging systems, software packages for dendritic analysis, advancements in miniaturized neurophotonic interfaces, and evaluation methods for neuroscience imaging tools. Overall, the article emphasizes the impact of open-source development on advancing neuroscience research and encourages collaboration among scientists from diverse fields for innovative discoveries. [Extracted from the article]

This work discusses microLED arrays as light sources for implementing optical sectioning structured illumination microscopy (OS‐SIM) and targeted illumination (TI) for neural imaging applications. We demonstrated a microstripe array to generate patterned light for OS‐SIM and an individually addressable 20 × 20 microLED array as a light source for implementing TI in a widefield imaging setup. [ABSTRACT FROM AUTHOR]

Background: The ability to self‐advocate or have a say in one's care is integral to personalised care after acquired brain injury (ABI). This study aimed to understand what constitutes self‐advocacy and associated barriers and facilitators throughout hospital transitions and into the community. Method: Qualitative methodology was employed with semistructured interviews conducted with 12 people with ABI and 13 family members. Interviews were conducted at predischarge (in‐person or via telephone) and 4 months postdischarge (via telephone) from the brain injury rehabilitation unit of a tertiary hospital. Data were thematically analysed using a hybrid deductive–inductive approach. Results: Self‐advocacy reflects the process of reclaiming agency or people's efforts to exert influence over care decisions after ABI. Agency varies along a continuum, often beginning with impaired processing of the self or environment (loss of agency) before individuals start to understand and question their care (emerging agency) and ultimately plan and direct their ongoing and future care (striving for agency). This process may vary across individuals and contexts. Barriers to self‐advocacy for individuals with ABI include neurocognitive deficits that limit capacity and desire for control over decisions, unfamiliar and highly structured environments and lack of family support. Facilitators include neurocognitive recovery, growing desire to self‐advocate and scaffolded support from family and clinicians. Conclusion: Self‐advocacy after ABI entails a process of reclaiming agency whereby individuals seek to understand, question and direct their ongoing care. This is facilitated by neurocognitive recovery, growing capacity and desire and scaffolded supports. Research evaluating approaches for embedding self‐advocacy skills early in brain injury rehabilitation is recommended. Patient or Public Contribution: Two caregivers with lived experience of supporting a family member with ABI were involved in the design and conduct of this study and contributed to and provided feedback on the manuscript. [ABSTRACT FROM AUTHOR]