Adaptation-induced sharpening of orientation tuning curves in the mouse visual cortex

Abstract

Objective Orientation selectivity is an emergent property of visual neurons across species with columnar and noncolumnar organization of the visual cortex. The emergence of orientation selectivity is more established in columnar cortical areas than in noncolumnar ones. Thus, how does orientation selectivity emerge in noncolumnar cortical areas after an adaptation protocol? Adaptation refers to the constant presentation of a nonoptimal stimulus (adapter) to a neuron under observation for a specific time. Previously, it had been shown that adaptation has varying effects on the tuning properties of neurons, such as orientation, spatial frequency, motion and so on. Basic methods We recorded the mouse primary visual neurons (V1) at different orientations in the control (preadaptation) condition. This was followed by adapting neurons uninterruptedly for 12 min and then recording the same neurons postadaptation. An orientation selectivity index (OSI) for neurons was computed to compare them pre- and post-adaptation. Main results: We show that 12-min adaptation increases the OSI of visual neurons (n = 113), that is, sharpens their tuning. Moreover, the OSI postadaptation increases linearly as a function of the OSI preadaptation. Conclusion The increased OSI postadaptation may result from a specific dendritic neural mechanism, potentially facilitating the rapid learning of novel features.

Distinct mechanisms of visual and sound adaptation in the cat visual cortex

“…The drifting sine-wave gratings were presented unidirectionally in eight possible orientations (base set) and were randomly presented 25 times for 4 s each, with an inter-stimulus interval of 1-3 s. After that a non-optimal orientation was presented for 12 minutes followed by the presentation of the base set again (beginning with the presentation of the adapter). This protocol has been frequently employed in other investigations (Marshansky et al, 2011;Bachatene et al, 2012bBachatene et al, , 2015bBachatene et al, , 2015aChanauria et al, 2016;Ouelhazi et al, 2024).…”