Figure 2. PCx Neurons Are Insensitive to Single-Glomerulus Activation.

(A) Odor-evoked response in a PCx neuron. Shaded box, odor delivery. Gray trace, respiration.

(B) Expanded view from (A) showing firing during a single inhalation. Vertical line, inspiration peak.

(C) Mean change in odor-evoked firing rate averaged across all M/Ts, aligned to inspiration peak (vertical line). Data show most effective odorant for each neuron (25 cells, 13 odorants/cell).

(D) Mean odor-evoked activity of PCx neurons averaged across all odors and cells. (23 cells, 4–13 odorants/cell).

(E) In the same odor-responsive PCx neuron shown in (A), uncaging at single MOB locations generated no firing. Vertical lines indicate uncaging pulses at various scan grid locations (7/96 shown).

(F) Expanded view from (E). Individual MOB sites were consistently ineffective at driving PCx firing over several repeated uncaging trials.

(G) Mean change in M/T firing rate produced by single-site uncaging in MOB, calculated for each cell’s most effective uncaging site (n = 26 cells).

(H) Mean change in PCx firing rate for single-site uncaging (n = 31 cells; note expanded scale relative to [D] and [G]). Despite robust M/T activation, PCx neurons were consistently unresponsive. See also Figure S2.