Table 1

Overview of included studies

Technique, study	Sample size^*	Within/between	Sex	OXT dose, IU	Task used	Brain areas analyzed	Effects of OXT
fMRI
Baumgartner et al.23	49 (23 PBO, 26 OXT)	Between	M	24	Trust game	Amygdala, brainstem, caudate, putamen, insula, thalamus	Increased trust in partner after trust had been violated
Domes et al.24	13	Within	M	24	Implicit facial emotion processing by identifying sex of fearful, angry and happy faces	Amygdala, temporal pole, TPJ, thalamus, PFC	Increased ability to identify emotions
Domes et al.25	16	Within	F	24	Explicit facial emotion processing by rating arousal of fearful, angry and happy faces	Amygdala, brainstem, temporal pole, STG, fusiform gyrus, insula, PFC, thalamus	Greater arousal in rating facial emotions
Gamer et al.26	46 (23 PBO, 23 OXT)	Between	M	24	Explicit facial emotion processing by classifying emotion of fearful and happy faces	Amygdala, superior colliculus	Increased ability to identify emotions; gaze starts at mouth and is redirected to eyes for longer period
Kirsch et al.27	15	Within	M	27	Implicit facial emotion processing by matching fearful and angry faces	Amygdala, brainstem	Increased ability to identify emotion
Labuschagne et al.28^†^‡	18	Within	M	24	Implicit facial processing by matching angry, fearful, happy and neutral faces	Amygdala	Insignificant decreases in amygdala activity
Labuschagne et al.29^†	18	Within	M	24	Explicit facial processing using emotional classification of sad, happy and neutral faces	mPFC, ACC, thalamus, STG	General attenuation in areas associated with processing social stimuli, cognitive control and emotion regulation
Lischke et al.30	14	Within	F	2	Explicit processing by rating emotional arousal of negative, positive and neutral scenes	Amygdala, temporal pole, fusiform gyrus	Increased threat sensitivity in the amygdala to scenes depicting social and nonsocial threat; no changes in eye tracking
Petrovic et al.31	27 (12 PBO, 15 OXT)	Between	M	32	Aversely conditioned face processing by rating likeability of faces that were previously paired with a negative experience	Amygdala, ACC, vlPFC, fusiform area	Increased likeability of faces even after being linked to aversive stimuli
Pincus et al.32	9	Within	1M/8F	40	Explicit emotional processing using Reading of the Mind in the Eyes test by emotional classification	Caudate, amygdala, ACC, STG, GP	OXT increased activity in areas associated with reward and processing of social stimuli
Riem et al.33^§	42 (21 PBO, 21 OXT)	Between	F	24	Auditory exposure to babies crying	Amygdala, insula	Decrease in amygdala to sound clips of crying babies
Riem et al.34	42 (20 PBO, 22 OXT)	Between	F	16^¶	Auditory exposure to infant laughter	Connectivity between the amygdala and the OFC, ACC, hippocampus, precuneus, supramarginal gyri and MTG	Increased functional connectivity between the amygdala and other areas involved in regulating emotion and decrease in amygdala when listening to laughter over control noise
Rilling et al.35	60 (34 PBO, 26 OXT)	Between	M	24	Altruistic interaction	Amygdala, caudate, ventral PFC, insula, putamen	Differences in activity in reciprocated and unreciprocated cooperativism; increase in amygdala only in reciprocated interaction
Singer et al.36	20	Between	M	32	Empathy for pain and experience of pain	PFC, OFC, amygdala	No significant observations in response to viewing their partner in pain; reduced amygdala activation when receiving painful stimulation
Sripada et al.37	15	Within	M	24	Resting state connectivity	Amygdala to ACC/rmFC	Increased connectivity during resting state
Striepens et al.38	70 (35 PBO, 35 OXT)	Between	M	24	Implicit processing of social scenes using a memory task with negative and neutral pictures paired with nouns	Insula, amygdala	Increased memory for negative pictures at the expense of neutral stimuli; accompanied by an increase in the left insula and changes in connectivity between the insula and amygdala
Wittfoth-Schardt et al.39	21	Within	M	24	Implicit facial processing of familiar and unfamiliar faces	GP, MTG, caudate	Reduced activity and functional connectivity to the GP from reward-related regions to pictures of own child and unknown child
EEG
Born et al.40	17	Within	M	40	Auditory mismatch paradigm	N2 and P3	No effect of OXT
Fehm-Wolfsdorf et al.41	30	Between	M	20	Memory recall of 25 nouns, tone counting	Auditory evoked potentials	No effect of OXT on memory or auditory stimuli
Huffmeijer et al.42	47	Between	F	15.6	Altruistic interaction	Frontal asymmetry	Increased donations from OXT corresponded with decrease in left/increase in right frontal activity
Huffmeijer et al.43	48	Within	F	16	Combination of feedback processing and facial processing	VPP and LPP	More positive VPP and LPP after OXT, which was heightened more for those experiencing less love withdrawal
Perry et al.44	24	Within	M	24	Point light experiment to mimic biological and nonbiological motion	μ rhythms	Better able to identify biological movement, which corresponded to μ suppression across the whole scalp

ACC = anterior cingulate cortex; EEG = electroencephalography; F = female; fMRI = functional magnetic resonance imaging; GP = globus pallidum; LPP = late positive potential; M = male; mPFC = medial prefrontal cortex; MTG = middle temporal gyrus; OXT = oxytocin; PBO = placebo; PFC = prefrontal cortex; rmFC = rostromedial frontal cortex; STG = superior temporal gyrus; TPJ = temporoparietal junction; vlPFC = ventrolateral prefrontal cortex; VPP = vertex positive potential; VTA = ventral tegmental area.
↵* Sample size incudes only the participants in the OXT and PBO samples. Other participants may have been included in other arms of the study.
↵† Also included 18 patients with generalized anxiety disorder, but only results from healthy controls are reported.
↵‡ Excluded from analysis other than that of the amygdala because no direction of effects were reported.
↵§ Also included patients with depression, but only results from healthy controls are reported.
↵¶ Originally reported as 20 IU, but a subsequent erratum confirmed it was 16 IU.