Figure 2.

Amplification of Weak Optogenetically Evoked Inputs from Basal Dendrites of Layer 2/3 Pyramidal Neurons during Depolarized Phases of Slow Network Activity

(A) Reconstruction of example layer 2/3 pyramidal neuron showing the soma (black), apical dendrites (green), and basal dendrites (orange), with the basal dendrite two-photon stimulation site highlighted by cyan arrowhead. Inset shows in vivo image of Alexa-Fluor-594-filled dendrite in red and optogenetic stimulation site in cyan.

(B) Overlaid mean OP_bas from 2 example cells show a (left) decreased and (right) increased response during V_dep.

(C) Population average OP_bas from V_hyp and V_dep.

(D) Amplitude of OP_bas in V_dep and V_hyp is not significantly different. Gray lines show data from individual cells, filled circles with error bars the mean ± SD.

(E) OP_bas half-width is significantly longer during V_dep than V_hyp.

(F) A negative correlation between the ratio of the OP_bas amplitude in V_dep:V_hyp and V_hyp OP_bas amplitude in awake (purple) and anesthetized (black) mice results in smaller amplitude inputs increasing and larger amplitude inputs decreasing in amplitude during V_dep. Correlations performed on the V_dep:V_hyp amplitude and log₁₀ of the V_hyp OP_bas amplitude are shown. Black and purple lines are single exponential fits.