Biology subjects

Lousada, E.

Publications and source records attributed to Lousada, E..

3 recordsLinked to original sources

bioRxiv2026

Open-BEATBox: an open-source autonomous operant chamber for high-throughput data acquisition of complex behaviour

Behavioural neuroscience increasingly relies on rodent models to investigate the neural mechanisms underlying cognition in health and disease. However, conventional operant testing is typically restricted to short daily sessions that require frequent experimenter intervention and often rely on food or water restriction. These constraints limit behavioural sampling, disrupt natural activity patterns, and introduce variability associated with handling and experimental schedules.Here, we present the Open Platform for Experimental Neuroscience Behavioural and Autonomous Box (Open-BEATBox), an open-source, autonomous home-cage platform that enables continuous, self-paced assessment of complex cognitive behaviour in mice. By allowing animals to live in the testing environment throughout the experiment, Open-BEATBox supports longitudinal behavioural assessment across different cognitive tasks while minimizing experimenter intervention and preserving natural circadian activity. The platform is modular, customizable, and designed to accommodate a broad range of operant paradigms and integration with chronic neural recording and neuromodulation technologies.Using a visual reversal-learning task, we show that continuous autonomous testing generates approximately ten times more completed trials during reversal learning than conventional session-based protocols while reducing experimenter workload without evidence of major adverse effects on the welfare measures assessed. The flexibility of the platform further enables implementation of additional cognitive paradigms, including uncertainty-based decision-making tasks.Together, Open-BEATBox provides an accessible open platform for longitudinal cognitive phenotyping, facilitating the collection of large longitudinal behavioural datasets and creating new opportunities to combine continuous behavioural assessment with modern systems neuroscience approaches.

neuroscience↗

bioRxiv2023

Expression profiling of the learning striatum

How learning reshapes the brain across temporal and spatial scales, from molecular to cellular levels, remains a fundamental question in neuroscience. In the striatum, ventromedial, dorsomedial and dorsolateral subregions are differentially recruited during early to late learning on a neurophysiological level. Here, we profile the transcriptome of these subregions across 396 biopsies from 66 mice to map molecular dynamics at three learning stages of a visual discrimination task. We find a strong transcriptional change during the early phase that diminishes towards later learning and is indistinguishable among subregions. The 818 genes altered during learning are enriched for neuronal processes, but also include circadian, vascular, and oligodendrocyte-related pathways. We provide a web application for this large learning-related expression dataset, enabling interactive exploration of genes, gene sets, and transcription factor activity, and suggest that this framework will be broadly useful for diverse neuroscience questions.

neuroscience↗

bioRxiv2021

Reduced axon caliber in the associative striatum of the Sapap3 knockout mouse

Pathological repetitive behaviors are a common feature of different neuropsychiatric disorders such as obsessive-compulsive disorder or Gilles de la Tourette syndrome. The Sapap3 knockout mouse (Sapap3-KO) is the current reference model used in translational psychiatry to study co-morbid repetitive behaviors, presenting both compulsive-like as well as tic-like behaviors. Consistent with clinical and fundamental research literature relating compulsive-like symptoms to associative cortico-striatal dysfunctions and tic-like symptoms to sensorimotor cortico-striatal dysfunctions, abnormalities comprising both circuits have been described in this mouse model. Findings reported on these mice point towards not only macro-, but also micro-circuitry deficits, both of which can be affected by neuronal structural changes. As such, in the present study, we aimed to investigate structural changes in associative and sensorimotor striatal areas that could affect information conduction. We used AxonDeepSeg, an open-source software to automatically segment and measure myelin thickness and axon caliber, and found that axon caliber, the main contributor for changes in conduction speed, is specifically reduced in the associative but not the sensorimotor striatum of the Sapap3-KO mouse. This smaller axon caliber in Sapap3-KO mice is not a general neuronal feature of this region, but specific to a subpopulation of axons with large caliber. These results point to a primary structural deficit in the associative striatum, affecting signal conduction and consequent connectivity.

neuroscience↗