Balancing dynamic rocks

Scoliosis

"The handedness of 254 girls with idiopathic scoliosis, minimum age eight years at diagnosis, attending Our Lady's Hospital was related to their scoliosis convexity. Curve patterns were assigned to right or left on the basis of the convexity of the low thoracic component only, regardless of primary curve. The curve pattern matched handedness in 82%. Of 228 right-handed children, 197 had a right convex curve pattern; of 26 left-handed children, 12 had a left convex pattern. The correlation between scoliosis configuration and handedness was statistically significant. This is in contrast to the findings of previous studies, which have considered convexity only, without reference to the configuration of the whole spine. The implication of this finding is that scoliosis is associated with cortical functions."

Older study there has been a great deal of water under the bridge since this was written with evidence for and against.

Polly's eyeing the cracker

"Individual preference for the use of one limb over the other to explore the environment or manipulate objects is common trait among vertebrates. Here, we explore the hypothesis that limb preference is determined by the engagement of a particular cerebral hemisphere to analyse certain stimuli. We recorded the eye and foot preferences of 322 individuals from 16 species of Australian parrots while investigating potential food items. Across all species, eye preferences explained 99 per cent of the variation in foot use in Australian parrots. The vast majority of species showed significant relationships between eye and foot preferences at the population level"


Static Rocks

In a dynamic system at a key structural interface what could be the outcome of a small force not applied equally? Many people have a minor scoliosis with no significant ill effects.

Rocks for my head