Table 1.

Main effects of tickling (T) and of anticipation (A) and correlating activity of (A) and of (T) with the laughter that was produced during (T)

Activated brain region		MNI Coordinates (peak x y z)/ Cluster size (voxels)				Z-score
Main effects	Side	T		A		T	A
Periaqueductal gray ext. into Midbrain tegmentum Cond. (A): ventral tegmental area	R	9-32-22	10357	0-25-22		6.92	3.94*
	L	−5-31-10	10357			7.54
Lateral hypothalamus	R	5-15-12	10357			6.57
	L	−5-13-12	10357	−5-15-8		6.58	3.87*
Posterior insula (gyri longi insulae)	R	38-1-16	10357			6.57
	L	−38-6-16	578			6.67
Mid-insula (gyri breves insulae)	R	40 13 2	10357			6.96
	L	−42 4 2	10357			6.69
Dorsal anterior insula (gyri breves insulae)	R					a
	L	−31 25 6	10357	−30 25 6	64	5.52	5.45
Ventral anterior insula (gyri breves insulae)	R	33 18-8		33 26-4	37	3.97*	5.58
	L	−35 23-8				4.25*
Inferior frontal gyrus/lateral orbital gyrus/piriform cortex	R	29 11-16	10357			4.82
	L	−30 9-16	39			5.74
Inferior frontal gyrus (pars opercularis)	R	50 16-2	10357			6.85
	L	−50 18-4	10357			5.50
Thalamus (VA, VL, VP,CM, A)	R	12-24 4	10357			5.55
	L	−17-15 6	10357			5.96
Pallidum/putamen	R	15 2-4	10357			5.50
	L	−17-5 0	10357			5.70
Nucleus accumbens	R		10357	10 7-2	13	a	4.98
	L		10357	−11 4-4	44	a	5.79
Amygdala/hippocampus	R	29-6-24	10357			5.18
	L	−29-8-24	578			5.66
Cerebellum (lobus anterior)	R/L	0-43-14	10357			7.43
Post. superior temporal sulcus	R	52-20-6	10357			6.58
Laughter correlation
Dorsal anterior insula	R			34 30 8			3.98*
Midbrain tegmentum extending to periaqueductal gray	R	10-29-6	46			3.73*

FMRI-activation sites were thresholded at P < 0.05 (FWE) corrected for multiple comparisons over the measured brain volume (voxel level). Moreover, according to the a priori hypothesis, a small volume correction (SVC) analysis was performed centered on the anterior insula, the hypothalamus and the midbrain (voxel level; P < 0.05; FWE corrected). Activations that were significant with the SVC analysis only are marked with ^*. Significant activations without a local maximum are indicated with ^a. Cluster sizes referring to multiple brain regions are italicized. Coordinates of maximal activation are displayed in MNI stereotactic space.