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Re: Authors reply re: The wrong ball

Reply: Right type of ball used in study

This is a forward-looking study in which modern day footballs were employed to assess the possible impact on the brain by heading. Old style heavy footballs, however, may well have been associated with brain damage as pointed out by Dr Breimer.

That the brains of woodpeckers would be full of plaques and signs of neuronal damage is a tall story. One case of cerebral amyloid angiopathy (a very common and unspecific ageing sign) has been reported in an aged great spotted woodpecker (Nakayama H, et al., Neurobiol Aging. 1999 Jan-Feb;20(1):53-6). In contrast, the woodpecker is very well adapted by evolution to repeated head blows by different anatomical structures that protect the brain (see May PR, et al., Lancet. 1976 Feb 28;1(7957):454-5; and Schwab IR, Br. J. Ophthalmol. 2002;86;843 for examples).

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Re: The wrong ball: old soccer balls much heavier and stiffer than modern

Dear Editor

It could be argued that this study has been performed with the wrong type of ball, one unlikely to reflect the type of brain stress inflicted on old footballers, because the old style ball absorbed dampness from the grass and became increasingly heavy and stiff, even if it had not been raining; on a rainy day the weight had increased a lot by the end of the match. Such balls needed power to kick, yet, as a corollary, they flew like cannonballs and were hard for goalies to stop, so many goals were scored towards the end of the match, often from distance shots. Heading them was something else.

I seem to remember that the brains of woodpeckers are full of plaques and signs of neuronal damage. Albeit that woodpeckers need not solve differential equations or even remember their latin names, notwithstanding they may be suitable models to study for serum biomarkers of repetitive brain trauma. Given that one would be studying the natural behaviour of woodpeckers ethics approval should be straightforward while repeating the study with a thoroughly doused old-style football might present a challenge.