  In order to understand the flow profiles of complex fluids, a crucial issue
concerns the emergence of spatial correlations among plastic rearrangements
exhibiting cooperativity flow behaviour at the macroscopic level. In this
paper, the rate of plastic events in a Poiseuille flow is experimentally
measured on a confined foam in a Hele-Shaw geometry. The correlation with
independently measured velocity profiles is quantified. To go beyond a
limitation of the experiments, namely the presence of wall friction which
complicates the relation between shear stress and shear rate, we compare the
experiments with simulations of emulsion droplets based on the
lattice-Boltzmann method, which are performed both with, and without, wall
friction. Our results indicate a correlation between the localisation length of
the velocity profiles and the localisation length of the number of plastic
events. Finally, unprecedented results on the distribution of the orientation
of plastic events show that there is a non-trivial correlation with the
underlying local shear strain. These features, not previously reported for a
confined foam, lend further support to the idea that cooperativity mechanisms,
originally invoked for concentrated emulsions (Goyon et al. 2008), have
parallels in the behaviour of other soft-glassy materials.
