In the article “Artificial CSF Motion Ensures Rhythmic Activity in the Developing CNS Ex Vivo: A Mechanical Source of Rhythmogenesis?” by Blaise Yvert, Claire Mazzocco, Sébastien Joucia, Adeline Langla, and Pierre Meyrand, which appeared on pages 8832–8840 of the June 15, 2011 issue, there was an error in reporting the measured speed of aCSF flow. The speed of aCSF flow was 22 μm/s for a perfusion rate of 10 μl/min, not 100 μl/min. The following corrections do not affect the main results of the study or their interpretation.
(1) In the Results section “Perfusion rate determines rhythm frequency” on page 8837, one should read:
“It must be noted that when decreasing the speed of perfusion, the characteristic aCSF rate corresponding to half of the maximum rhythm frequency was 100 μl/min (Fig. 7c, asterisk) and activity could be seen for rates as low as 10 μl/min. The speed of aCSF within a distance of 1 mm from the inlet corresponding to this rate of 10 μl/min was measured optically using 10 μm microparticles and found to be of 22 μm/s (see Materials and Methods).”
(2) In the penultimate paragraph of the Discussion on page 8839, one should read:
“Interestingly, the typical speed of aCSF that was necessary for the emergence of rhythmic activity was of the order of 200 μm/s but activity could be seen for speed as low as 20 μm/s (Fig. 7c), which corresponds to the estimated speed of CSF in the adult mouse ventricles due to the beating of motile ependymal cilia.”