7/ When she targeted the C2 barrel in vS1, she found that it reduced touch responsiveness in vS2 in a whisker-specific manner.

6/ She then lesioned the 'touch patch’ in vS2, and found that this diminished touch responses in vS1.

5/ She found that despite their rarity, multiwhisker cells carried a large share of touch activity in both directions.

4/ Lauren then used retrograde AAV injections in both areas, targeting just the portion of each area that responded to a specific whisker, and asked how somatotopically-matched regions communicated.

3/ Despite making up only ~1% of neurons, multiwhisker cells nevertheless carried a large fraction of the touch response superficially.

2/ Lauren first imaged L2-4 in both whisker S1 and S2 in mice with two spared whiskers. In both areas, neurons in deeper L2/3 and L4 were mostly responsive to single whiskers, whereas superficial neurons were broadly tuned and responded to multiple whiskers.

These cells are also far more likely to remain within-type than to switch to other types.

Broadly tuned cells also showed greater stability in terms of the correlation of touch responsiveness, measured using an encoding model, across days.

Cells with broader tuning on day 1 – multiwhisker or bidirectional single whisker neurons – were consistently more touch responsive.

Alisha studied drift using a two-whisker touch task, classifying neurons responsive to different combinations of forward and backward touches by both whiskers.