Learning enhances behaviorally relevant representations in apical dendrites

Learning alters cortical representations and improves perception. Apical tuft dendrites in Layer 1, which are unique in their connectivity and biophysical properties, may be a key site of learning-induced plasticity. We used both two-photon and SCAPE microscopy to longitudinally track tuft-wide calcium spikes in apical dendrites of Layer 5 pyramidal neurons in barrel cortex as mice learned a tactile behavior. Mice were trained to discriminate two orthogonal directions of whisker stimulation. Reinforcement learning, but not repeated stimulus exposure, enhanced tuft selectivity for both directions equally, even though only one was associated with reward. Selective tufts emerged from initially unresponsive or low-selectivity populations. Animal movement and choice did not account for changes in stimulus selectivity. Enhanced selectivity persisted even after rewards were removed and animals ceased performing the task. We conclude that learning produces long-lasting realignment of apical den..., Movies of apical dendrites were acquired by imaging genetically encoded calcium indicator with two-photon microscopy (planar imaging) or SCAPE microscopy (volumetric imaging). Microscopes were controlled by ScanImage in the case of two-photon or custom software in the case of SCAPE. Movies were motion corrected and segmented using CaImAn., , # Data from: Learning enhances behaviorally relevant representations in apical dendrites

[https://doi.org/10.5061/dryad.v6wwpzh5t](https://doi.org/10.5061/dryad.v6wwpzh5t)

## Description of the data and file structure

The goal of these experiments was to compare the responsiveness and selectivity of layer 1 apical tuft dendrites in barrel cortex before and after head-fixed mice learned a direction discrimination task.

### Files and variables

#### File: ApicalResponses.xlsx

**Description:** the overall responsiveness of apical tufts before, during, and after learning. Each row corresponds to one segmented apical tuft.

##### Variables

* *CS+* is the magnitude of the response (in fractional delta F/F0) for the rewarded direction
* *CS-* is the magnitude of the response (in fractional delta F/F0) for the unrewarded direction
* *Conditioning day* is the number of a session

#### File: ApicalSelectivity2p.xlsx

**Description:** the selectivity of individual apical tufts before, during...