Table 1.

Summary of studies included in the meta-regression analysis. All studies were performed with healthy study participants. Two studies report the data of the same sample (included only once in the meta-analysis) and two studies report subsamples of data already included in a meta-analysis, which were therefore omitted. Several studies contain multiple observations (e.g. from repeated measurements).

Study	Sample Size	Study description	Data report	Psilocybin administration
Umbricht et al., 2002	N = 18	EEG, auditory mismatch-negativity paradigm	5D-ASC (converted)	Oral administration Dosage: (1) 280 μg/kg body weight
Hasler et al., 2004	N = 8	Double-blind placebo-controlled within-subject design ECG, blood pressure, body temperature and further questionnaire assessment	5D-ASC	Oral administration as gelatin capsules Dosages: (1) 45 μg/kg body weight (2) 115 μg/kg body weight (3) 215 μg/kg body weight (4) 315 μg/kg body weight
Carter, Pettigrew, et al., 2005 (Same sample: Wittmann et al., 2007)	N = 12 (N = 12)	Double-blind placebo-controlled within-subject design Binocular rivalry paradigm, time reproduction, auditory sensorimotor synchronization task, finger tapping, spatial span test	5D-ASC	Oral administration as gelatin capsules Dosages: (1) 115 μg/kg body weight (2) 250 μg/kg body weight
Carter et al., 2007 (Subsample: Carter, Burr, et al., 2005)	N = 10 (N = 8)	Within-subject design with additional conditions: (2) placebo, (3) 50 mg ketanserin, (4) ketanserin + psilocybin, Multiple object tracking task, spatial working memory task	5D-ASC	Oral administration as gelatin capsules Dosage: (1) 215 μg/kg body weight
Vollenweider et al., 2007	N = 16	Double-blind placebo-controlled within-subject design Prepulse inhibition of acoustic startle response	5D-ASC (converted)	Oral administration as gelatin capsules Dosages: (1) 115 μg/kg body weight (2) 215 μg/kg body weight (3) 315 μg/kg body weight
Quednow et al., 2012	N = 16	Double-blind within-subject design with additional conditions: (2) placebo, (3) 40 mg ketanserin, (4) ketanserin + psilocybin, Prepulse inhibition of acoustic startle response, colour-word-Stroop test	5D-ASC (converted)	Oral administration as gelatin capsules Dosage: (1) 260 μg/kg body weight
Pokorny et al., 2016	N = 19 N = 17	Double-blind within-subject design with two groups (G1: N = 19, G2: N = 17) and additional conditions: (2) G1/G2: placebo, (3) G1: 20 mg buspirone, or G2: 3 mg ergotamine, (4) G1: buspirone + psilocybin, or G2: ergotamine + psilocybin	5D-ASC	Oral administration as gelatin capsules Dosage: (1) 170 μg/kg body weight (G1) (2) 170 μg/kg body weight (G2)
Kometer et al., 2012	N = 17	Double-blind placebo-controlled within-subject design EEG, facial emotional recognition task, emotional Go/NoGo task	11-ASC	Oral administration as gelatin capsules Dosage: (1) 215 μg/kg body weight
Schmidt et al., 2013 (Same sample: Schmidt et al., 2012)	N = 21 (N = 20)	Double-blind placebo-controlled within-subject design with additional condition: (2) S-ketamine EEG, auditory mismatch-negativity paradigm, backward masking paradigm with facial affect discrimination	11-ASC	Oral administration as gelatin capsules Dosage: (1) 115 μg/kg body weight
Bernasconi et al., 2014	N = 30	Placebo-controlled EEG, passive viewing of emotional face task	11-ASC	Oral administration as gelatin capsules Dosage: (1) 170 μg/kg body weight
Pokorny et al., 2017 (Subsample: Preller et al., 2016)	N = 33 (N = 21)	Double-blind placebo-controlled within-subject design Multifaceted empathy test, moral dilemma task ,fMRI, Cyberball task	11-ASC	Oral administration as gelatin capsules Dosage: (1) 215 μg/kg body weight
Lewis et al., 2020	N = 55	Randomized double-blind placebo-controlled, repeated measures design	11-ASC	Oral administration Dosages: (1) 160 ug/kg body weight (2) 215 ug/kg body weight
Smigielski et al., 2020	N = 17	Double-blind placebo-controlled within-subject crossover design, EEG, self-monitoring task	11-ASC	Oral administration as capsules Dosage:
				(1) 230 ug/kg body weight
Carbonaro et al., 2018	N = 20	Double-blind placebo-controlled within-subject design with additional conditions: (4) 400 mg/70 kg dextromethorphan Blood pressure, heart rate, pupil diameter, circular lights, balance, repeated administration of other questionnaires	11-ASC HRS MEQ30	Oral administration as gelatin capsules Dosages: (1) 143 μg/kg body weight (10 mg/70 kg) (2) 286 μg/kg body weight (20 mg/70 kg) (3) 429 μg/kg body weight (30 mg/70 kg)
Griffiths et al., 2006 (reported in Barrett et al., 2015)	N = 30	Double-blind within-subject design with additional conditions (data from unblended control condition not included): (2) 40 mg/70 kg body weight Methylphenidate Group setting, meetings with monitor before and after sessions	HRS MEQ30	Oral administration Dosage: (1) 429 μg/kg body weight (30 mg/70 kg)
Griffiths et al., 2011 (reported in Barrett et al., 2015)	N = 18	Double-blind placebo-controlled between-group crossover design Descending or ascending dosage order Group setting, meetings with monitor before and after sessions	HRS MEQ30	Oral administration as gelatin capsules Dosages: (1) 71 μg/kg body weight (5 mg/70 kg) (2) 143 μg/kg body weight (10 mg/70 kg) (3) 286 μg/kg body weight (20 mg/70 kg) (4) 429 μg/kg body weight (30 mg/70 kg)
Nicholas et al., 2018	N = 12	Lying on sofa with eye-shades headphones and music Preparation of participants with guides Blood sample, ECG	MEQ30	Oral administration as capsules Dosages (given in escalating order): (1) 300 μg/kg body weight (2) 450 μg/kg body weight (3) 600 μg/kg body weight

EEG: electroencephalogram; ECG: electrocardiogram; fMRI: functional magnetic resonance imaging.