The fourth group of interneurons did not exhibit delayed onset firing at threshold and displayed mostly irregular firing patterns (7/48; 15%; group 4 in Fig. 4A, Bf).
While different subtypes of interneurons are labeled in this mouse line, we found a strong bias towards reelin-expressing, dendritically targeting interneurons with firing patterns showing delayed onset firing around threshold and moderate firing adaptation at higher firing frequencies.
The firing patterns of the majority of GFP-labeled interneurons were characterized by delayed onset firing around threshold and continuous, regular firing at higher firing frequencies with moderate frequency adaptation ('adapting'adapting
Delayed onset firing was defined by the delay of the first spike exceeding 100 ms. Strongly adapting cells were defined as cells that stopped firing before the end of the current injection.
In addition, 10 of 11 interneurons with morphologies similar to neurogliaform cells (soma location in deep dendritic layers, compact multipolar morphology, axon ramifying close to soma; Fig. e.g. 4Ca,b) displayed delayed onset firing.
The swift onset of fire season here was unfolding nearly a year after the Waldo Canyon fire wrought widespread damage in Colorado Springs.
In addition, in these fibres cold thresholds are difficult to determine as they encode temperature through dynamic changes in firing pattern rather than onset of firing at a specific temperature (Hensel & Zotterman, 1951), and these were therefore not included in these analyses.
GFP-labeled interneurons mostly show delayed onset of firing around threshold, and regular firing with moderate frequency adaptation at more depolarized potentials.
We measured a slight increase in input resistance in Kv10.1−/− cells that is, however, not reflected in an earlier onset of firing or in an increased firing frequency after crossing the threshold.
The firing frequency vs. injected current relationship is non-linear (has a discontinuity near the onset of firing) and the action potential amplitude can be graded.
We will derive a 1D map that measures the phase difference between the onset of firing of the two cells.
