Paired Allen slice data leave mean first-response changes from 250 ms to 4 s uncertain after 50 Hz trains

We tested first-response changes between 250 ms and 4 s pauses after eight-pulse 50 Hz trains in the same detected Allen cortical connections. The paired sample had 680 connections in four species and synapse-type groups. Equal-donor mean changes were -0.00755 for mouse excitation, 0.06268 for mouse inhibition, -0.04076 for human excitation, and 0.14998 for human inhibition. All primary 98.75% donor bootstrap intervals included zero. The human inhibitory group had only four donors and is descriptive. A secondary four-pulse measure gave a positive interval in mouse inhibition. Absolute response deviations decreased in the larger samples, but measurement noise limits that result. These findings do not show equality, full response reset, or a common recovery rule. We provide protocol-specific extraction code, derived evidence, uncertainty draws, source hashes, a figure, and an independent point-estimate check. Slice selection, separate protocol trials, inferred donors, and uncertain fitted responses limit inference.

Allen Institute · synaptic recovery · paired protocols · circuit dynamics · null result