Table 1.

Drug effects on gamma frequency

	Saline	Nembutal (5 mg/kg)	MK-801 (0.05 mg/kg)
	56.5	51.9	57.3
		p = 6 × 10−5	p = 0.12
Rat 9245	56.1 Hz	50.5 Hz	57.0 Hz
		p = 3 × 10−8	p = 0.2
Rat 9244	56.7 Hz	52.5 Hz	58.0 Hz
		p = 0.002	—
Rat 9233	56.8 Hz	52.7 Hz	57.0 Hz
		p = 3 × 10−4	p = 0.9

Values are peak gamma frequencies, calculated by averaging across trials and 500 ms trial phases for each session and then averaging across sessions. p values are the results of t test comparisons of peak gamma frequency between drug and saline conditions. Top row shows means and p values across rats, and the bottom rows show means and p values within rats, across session. As a result of poor behavior in rat 9244, data collection under treatment with MK-801 was successfully obtained in only one session, so a within-rat comparison could not be made. Gamma frequency was consistently slower after administration of the barbiturate Nembutal (sodium pentobarbital), but gamma frequency after the NMDA antagonist MK-801 was not different from the saline condition.