Table 2.

Percentage of AM cells detecting AM with increases and decreases in activity

	A1		ML
	Nonsynchronized	Synchronized	Nonsynchronized	Synchronized
Increasing (AM)	21/32 65.6%	87/146 60.0%	24/37 64.9%	21/51 41.2%
Decreasing (AM)	7/32 21.9%	32/146 21.9%	13/37 35.1%	19/51 37.2%
Mixed Inc/Dec (AM)	4/32 12.5%	27/146 18.5%	0/37 0%	11/51 21.6%

Values on the left are count of cells that detect AM by changing firing rate or phase locking, values on the right are in percentage. Cells in each area are broken down into synchronized and exclusively nonsynchronized categories. Detection of AM is also broken down into cells that show an increase or decrease in firing rate for AM relative to firing rate to unmodulated stimuli, and “mixed” cells, which exhibit both increases and decreases in rate at different modulation frequencies. To aid in comparisons to more recently used nomenclature from the midbrain, increasing and decreasing cells correspond to band-enhanced (AM responses greater than the unmodulated noise response) and band-suppressed (AM responses less than the unmodulated noise response) of Kim et al. (2015). AM, amplitude-modulated; A1, primary auditory cortex; ML, middle lateral auditory cortex.