Article: Thalamic control of layer 1 circuits in prefrontal cortex.

Values are means ± SEM for each of the cell groups, except for the “slow ADP incidence.” The latter is the tally of cells in which a slow afterdepolarization (ADP) was observed relative to number tested. Details of the measurements are described in Materials and Methods. LS and NLS cells differed on all of the measures listed except postnatal age, input capacitance, and afterhyperpolarization latency (p < 0.02, Fisher's exact test for slow afterdepolarization incidence and Mann-Whitney U test for all others). The “Other L1 cell” group generally had values between the LS and NLS groups (exceptions are input resistance and capacitance, voltage sag amplitude, and afterhyperpolarization latency). Properties used to categorize the L1 interneurons into LS or NLS groups included the voltage sag measures, afterhyperpolarization amplitude, action potential latency (at threshold), slow afterdepolarization incidence, and spike frequency adaptation ratio. A variety of intrinsic properties are also presented for L2/L3 pyramidal cells as a reference for comparison with the L1 interneurons. Pyramidal cells had higher input capacitances, longer time constants, and larger/wider action potentials with slower afterhyperpolarizations than the L1 interneurons (p < 0.001, Mann-Whitney U test).