Microcephaly is a rare condition, but nevertheless has the potential to tell us a lot
about how the human brain evolved and what controls neurogenesis. In their review article on this topic, Gemma Thornton and Geoff Woods lead us through the genetics of primary microcephaly, highlighting the fact that four genes responsible for this condition are all critically associated with the centrosome and mitosis during neurogenesis in utero. Thus, this group of rare conditions with an incidence of between 1:30,000 and 1:2,000,000 may be able to provide unique insights into the processes that explain what
caused the human brain to evolve.

Jack Price, in his review article, rehearses the arguments for the utility of stem cells in the treatment of disorders of the CNS. He concentrates on four main types of stem cells for CNS repair; endogenous neural precursor cells and their recruitment; exogenously grown neural stem cells which are transplanted; ES cell culture and manipulation with subsequent engraftment and finally non neural stem cell transplants to replace damaged neuronal networks. This is a clearly written account by an acknowledged expert in
the field and is a very useful summary of what can seem a rather baffling, complex and often hyped field.

What is the best way to count cells in histological sections of nervous tissue? This is the question that Stan Lazic addresses in his review on stereology which is the target of our ‘Techniques in Neuroscience’ series in this issue of the ACNR. Stan takes us through the principles underlying the older and more modern approaches to stereology highlighting the limitation and advantages of the various different approaches. In so doing, he provides us with a very useful summary of an often neglected area of neuroscience research, but which is often critical in characterising anatomy and pathology in a range of neural structures both in health and disease.

Colour vision is a peculiar thing, as we assume that what we see as a certain colour is just that.Whilst we can assume this, and live our lives according to this rule, it is of course an artificial situation as Petroc Sumner explains. In this beautiful account in the ‘Visual Neurioscience’ series, he explains how the colour system operates in the human retina and its CNS projections, as well as how it varies in other species - such that you may be alarmed to know that your pet goldfish will be viewing you very differently to how you see yourself! Finally, he touches upon adaptation and colour constancy, in what is a very interesting and stimulating article.

The use of cervical collars is widely advocated in some circles, whilst frowned upon by others primarily because there is often confusion as to what are the indication, uses and types of such devices. We are therefore fortunate to have Datta et al take us through this issue. They highlight the different types of orthosis for neck control including those used to treat traumatic injuries of the cervical spine as well as those considered in patients with neurological disorders such as motor neuron disease.

The recent ABN case report winner by Monaghen et al is written up in this issue of the ACNR and makes for sober reading. The patient had a Wernicke-Korsakoff syndrome with the ‘pulvinar sign’ and had treatment with TPN which did not contain thiamine. This nicely written-up case thus highlights that making a diagnosis is one thing, but making sure it is probably treated is another.

The diagnosis of patients with idiopathic normal pressure hydrocephalus is often fraught with difficulty; do they truly have it, or are the enlarged ventricles simply secondary to a neurodegenerative, atrophic or vascular small vessel process? In the article by Peter Whitfield and Maric Czosnyka, we are treated to a superlative account of the best
approach, highlighting the positive predictive value of the various tests employed to help in the diagnosis, and thus treatment of this condition, including shunting. In addition, a pragmatic account is given on the use and maintenance of shunts in this, and other hydrocephalic conditions which, overall, produces a well-rounded and instructive
account of a complex area of neurological practice.

Dr Felix Geser, in the historical section of ACNR, explores the roots of neuropathology and clinical neuroscience. He takes us through its origins in the pre 20th Century, highlighting the main players and their contribution to the field, and how this evolved out of a number of disparate, separate strands of scientific practice and discovery. The article is a fascinating personal perspective on a very exciting time of scientific and medical discovery.

Finally, we have our usual book and journal reviews - the latter is dominated by Dr Coles and his passion for calculating numbers needed to treat! So we hope you enjoy this latest issue and don’t forget to visit the website and feedback suggestions for improvement.

Roger Barker
Roger@acnr.co.uk