Biology subjects

Lien, A. D.

Publications and source records attributed to Lien, A. D..

3 recordsLinked to original sources

bioRxiv2025

A standardized and reproducible behavioral protocol to elicit visual spatial attention in mice

Understanding how neural activity gives rise to cognitive processes such as selective attention is a fundamental goal of neuroscience. An important but often overlooked advance towards this goal requires the development and sharing of rigorous and reproducible behavioral tasks across labs; this is particularly important given the recent surge in studies of cognition and perception in mice. Here, we developed a standardized training protocol for head-fixed mice to become experts in a psychometric visual contrast detection task in just 17 days. Experts detected stimuli at two distinct spatial locations for several hundred trials per day. As consecutive trials elapsed at either location, the speed, accuracy, and contrast sensitivity of visual perception improved - all hallmarks of spatial attention improving performance, as seen in primates. These findings validate the efficacy of this protocol to reveal multiple aspects of selective spatial attention in mice, establishing a rigorous and reproducible tool for the community.

neuroscience↗

bioRxiv2025

Highly selective visual receptive fields in mouse frontal cortex

A hallmark of the mammalian visual system is spatial information processing. This relies on feedforward activity spanning multiple brain areas, and on interconnected neurons with spatial receptive fields (RFs) aligned across these areas. This organization allows neurons to iteratively analyze information from the same point of the visual field. It remains unclear if this framework extends beyond the visual system, especially into cognitive areas of frontal cortex that exert feedback control over early sensory areas. Here, we surveyed the mouse frontal cortex (anterior cingulate and secondary motor areas), and discovered neurons with low latency, highly localized visual RFs. Just like in visual cortex, responses were often highly selective for bright or dark stimuli. The responses lagged visual cortical areas by only [~]25 ms, and their RFs were comparable in size. Further, the representation of visual space in frontal cortex showed a strong bias for the central (binocular) visual field, but there was no evidence of a topographically organized retinotopic map. Importantly, these visual responses were abolished by optogenetic silencing of visual cortex, revealing a causal role for feedforward hierarchical connectivity that extends visual spatial processing directly into motor and cognitive regions of mouse frontal cortex.

neuroscience↗

bioRxiv2018

Emergence of Direction Selectivity at the Convergence of Thalamo-Cortical Synapses in Visual Cortex

Detecting the direction of an objects motion is essential for our representation of the visual environment. Visual cortex is one of the main stages in the mammalian nervous system where motion direction may be computed de novo. Experiments and theories indicate that cortical neurons respond selectively to motion direction by combining inputs that provide information about distinct spatial locations with distinct time-delays. Despite the importance of this spatiotemporal offset for direction selectivity its origin and cellular mechanisms are not fully understood. We show that ~80+/-10 thalamic neurons responding with distinct time-courses to stimuli in distinct locations contribute to the excitation of mouse visual cortical neurons during visual stimulation. Integration of thalamic inputs with the appropriate spatiotemporal offset provides cortical neurons with the primordial bias for direction selectivity. These data show how cortical neurons selectively combine the spatiotemporal response diversity of thalamic neurons to extract fundamental features of the visual world.

neuroscience↗