X. Li1, Neil Roberts1, M. Perrins1, and G. Vingerhoets2
The
human brain is structurally asymmetric and typically described as if it has
been subject to a rotational moment about the vertical axis of the body, the
so-called “Yakovlevian Torque”. In subjects with situs inversus totalis (SI)
the internal organs of the body are transposed and it has been obvious to
question whether in these subjects brain torque is also reversed? We recruited
16 subjects with SI and 16 age, sex and education matched controls (SS) and
applied state of the art image analysis techniques to investigate the extent to
which brain asymmetry is reversed on 3D MR images in these subjects. Analysis
of the frontal and occipital petalia has confirmed previous reports of
significant reversal of the latter but not the former on average in SI, and has
also shown that reversed asymmetry is not present in all individuals with SI.
