Raymond Tallis has a superb piece in today's Guardian on the ludicrousness of some of the claims that are made by those who use functional brain imaging to try and explain that who we are and what we do is somehow revealed by the particular bits of the brain that 'light up' in big imaging bits of kit. HERE.
In the piece he references a Nature Neuroscience Review paper by Katherine Button and friends. The abstract reads as follows:
A study with low statistical power has a reduced chance of detecting a true effect, but it is less well appreciated that low power also reduces the likelihood that a statistically significant result reflects a true effect. Here, we show that the average statistical power of studies in the neurosciences is very low. The consequences of this include overestimates of effect size and low reproducibility of results. There are also ethical dimensions to this problem, as unreliable research is inefficient and wasteful. Improving reproducibility in neuroscience is a key priority and requires attention to well-established but often ignored methodological principles.