Table 1.

Numbers and proportions of recorded neurons across different classes

2433 neurons recorded from 5 rats	Putative projection/excitatory (2182 neurons, 89.7% of total)	Putative interneuron/inhibitory (143 neurons, 5.9% of total)	Ungrouped (108 neurons, 4.4% of total)
Regular firing = 1383 neurons, 56.8% of total (conservative boundary = 1015, 41.7%)	1301 neurons, 53.5% of total	43 neurons, 1.8% of total	46 neurons, 1.9% of total
Burst firing = 598 neurons, 24.6% of total (conservative boundary = 189, 7.8%)	554 neurons, 22.8%	16 neurons, 0.66%	28 neurons, 1.2%
Fast spiking = 185 neurons, 7.6% of total (conservative boundary = 58, 2.4%)	87 neurons, 3.6%	82 neurons, 3.4%	16 neurons, 0.66%
Ungrouped = 267 neurons, 11.0% of total (conservative boundary = 1171, 48.1%)	240 neurons, 9.9%	9 neurons, 0.37%	18 neurons, 0.74%

Note: Classifications by firing patterns (rows) were made by visual inspection of clusters formed by autocorrelation features, but analyses were complimented with more restrictive classification boundaries, referred to in table as “conservative boundary” for comparison. Note that although a number of fast-spiking neurons exhibited waveform shapes that fell under the heading of “putative projection/excitatory” neurons, there is no reason to believe that these neurons were, in fact, projection cells or that they used glutamate as a neurotransmitter. Analyses in the present paper typically focused on 3 neuron classes: regular-firing projection neurons, burst-firing projection neurons, and fast-spiking inhibitory neurons (bold text).