  We present a search for non-Gaussianity in the WMAP first-year data using the
two-point correlation function of maxima and minima in the temperature map. We
find evidence for non-Gaussianity on large scales, whose origin appears to be
associated with unsubstracted foregrounds, but which is not entirely clear. The
signal appears to be associated most strongly with cold spots, and is more
pronounced in the Southern galactic hemisphere. Removal of the region of sky
near the galactic plane, or filtering out large-scale modes removes the signal.
Analysis of individual frequency maps shows strongest signal in the 41GHz Q
band. A study of difference maps tests the hypothesis that the non-Gaussianity
is due to residual foregrounds and noise, but shows no significant detection.
We suggest that the detection is due to large-scale residual foregrounds
affecting more than one frequency band, but a primordial contribution from the
Cosmic Microwave Background cannot be excluded.
