Table 4.

Summary statistics of drug classes included in the meta-analysis for fear-potentiation and the non-cued startle baseline response

Drug classes	Articles	Experiments	Animals	SMD [95% CI]	I2 (%)
Fear potentiation
GABA-ergic system
Benzodiazepines	22	32	762	− 1.13 [− 1.37, − 0.88]	59.3
GABAA receptor inverse agonists	3	5	98	0.01 [− 0.48, 0.49]	36
Serotonergic system
Buspirone	6	7	134	− 1.72 [− 1.50, − 0.74]	86
5-HT1A receptor agonists	3	7	260	− 1.1 [− 1.4, − 0.77]	30
5-HT1A receptor antagonists	3	5	110	− 0.7 [− 1.23, − 0.25]	39
Glutamatergic system
mGluR2,3 agonists	3	7	102	− 1.71 [− 2.59, − 0.83]	73
Non-cued startle baseline response
GABA-ergic system
Benzodiazepines	22	29	714	− 1.08 [− 1.39, − 0.76]	74
GABAA receptor inverse agonists		5	98	0.26 [− 0.13, 0.64]	0
Serotonergic system
Buspirone	6	7	134	0.36 [− 0.40, 1.13]	80
5-HT1A receptor agonists	3	7	256	− 0.21 [− 0.69, 0.28]	72
5-HT1A receptor antagonists	3	5	110	− 0.65 [− 1.02, − 0.28]	0
Glutamatergic system
mGluR2,3 agonists	1	2	32	Not pooled

Drug classes were omitted from the analysis if these contained fewer than five experiments, from fewer than three different articles

SMD standardized mean difference (Hedge’s g), CI confidence interval