The circuitry of the brain is too complex to be completely specified by genetic information – at least not down to the level of each connection. There are hundreds of billions of neurons in your brain, each making an average of 1,000 connections to other cells. There are simply not enough genes in the genome […]

A pair of papers from the lab of Fred Gage has provided new insights into the molecular and cellular processes affected in Rett syndrome. This syndrome is associated with arrested development and autistic features. It affects mainly girls, who typically show normal development until around age two, followed by a sudden and dramatic deterioration of […]

An amazing study just published in Cell starts out with fruit flies insensitive to pain and ends up with what looks very like a synaesthetic mouse. Penninger and colleagues were interested in the mechanisms of pain sensation and have been using the fruit fly as a model to investigate the underlying biological processes. Like any […]

Whole-genome sequencing is a game-changer for human genetics. It is now possible to deduce every base of an individual’s genome (all 6 billion of them – two copies of 3 billion each) for a couple of thousand euros, and dropping. (Yes, euros). Even Ozzy Osbourne just got his genome sequenced! For researchers searching for the […]

Colour does not exist. Not out in the world at any rate. All that exists in the world is a smooth continuum of light of different wavelengths. Colour is a construction of our brains. A lot is known about how the brain does this, beginning with complicated circuits in the retina itself. Thanks to a […]

I wouldn’t usually discuss politics in a blog like this, but a recent story caught my eye, as it provides an example of the depressing and sometimes bizarre level of scientific illiteracy among elected officials or some people who hope to be elected. The example is from the United States, which is an easy target […]

Just how special is the human brain? Compared to other mammals, the thing that stands out most is the size of the cerebral cortex – the thick sheet of cells on the outside of the brain, which is so expanded in humans that it has to be folded in on itself in order to fit […]

Wild-type is the term geneticists use to refer to non-mutants. It literally means organisms that are the same, genetically, as those in the wild, compared to ones that have been grown under coddled conditions in the lab for generations, going soft in the absence of natural selection, or that are specifically mutant at some gene […]

The idea that our genes can affect many of the traits that define us as individuals, including our personality, intelligence, talents and interests is one that some people find hard to accept. That this is the case is very clearly and dramatically demonstrated, however, by a number of genetic conditions, which have characteristic profiles of […]

Studies linking some aspect of parental behaviour with some trait in their offspring are depressingly common in the sociological literature. Though these studies typically only report a correlation between parental behaviour and whatever the trait is in the offspring, the implication, and often the explicit conclusion, is that one causes the other. These kinds of […]

To many people, the term “autism” suggests a specific disorder – one with characteristic and recognizable symptoms, presumably reflecting the same underlying cause.  In fact, no such disorder exists.  Autism refers to a variable spectrum of symptoms – including deficits in social interaction, impaired communication (especially a delay in developing language), narrow, restricted interests and […]

Mirrored from http://wiringthebrain.blogspot.com Clever, elegant and extremely powerful – techniques to activate specific sets of neurons with light have the potential to revolutionise cellular and systems neuroscience. Optogenetics has already been used to address a number of questions which have been resistant to answer by other techniques, and also holds great promise for neurotherapeutics and […]

In a recent post, I presented the evidence that sexual preference is strongly influenced by genetic variation (http://www.gnxp.com/wp/uncategorized/sexual-orientation-–-in-the-genes). Here, I discuss the neurobiological evidence that shows that the brains of homosexual men and women are wired differently from those of their heterosexual counterparts. First, we must consider the differences between the brains of heterosexual males […]

The manipulative con-man. The guy who lies to your face, even when he doesn’t have to. The child who tortures animals. The cold-blooded killer. Psychopaths are characterised by an absence of empathy and poor impulse control, with a total lack of conscience. About 1% of the total population can be defined as psychopaths, according to […]

Mirrored from http://wiringthebrain.blogspot.com Is homosexuality a lifestyle choice or an innate biological disposition? The idea that it is a choice is certainly widespread – a part of several mainstream religious doctrines and political ideologies – and is used to condone significant discrimination against homosexuals and the criminalization of homosexual behaviour. But what does the science […]

Mirrored from http://wiringthebrain.blogspot.com The criteria used to assign patients to specific psychiatric disease categories are set out in the Diagnostic and Statistical Manual of Mental Disorders, published by the American Psychiatric Association. (There is also a World Health Organisation equivalent, the International Classification of Disease). Every so often, these criteria are revised to reflect new […]

Reading is not a skill that comes naturally. Unlike learning spoken language, which the human brain has evolved to absorb almost effortlessly, learning to read is a protracted and difficult process. It involves the categorical association of arbitrary visual symbols with phonemes and also the ability to break words down into component phonemes. It thus […]

Mirrored from http://wiringthebrain.blogspot.com Why are genetically identical monozygotic twins not phenotypically identical? They are obviously much more similar than people who do not share all their DNA, but even in outward physical appearance are not really identical. And when it comes to psychological traits or psychiatric disorders, they can be quite divergent (concordance between monozygotic […]

Mirrored from http://wiringthebrain.blogspot.com/ Mental illness is surprisingly common. About 10% of the population is affected by it at any one time and up to 25% suffer some kind of mental illness over their lifetime. This has led some people (many people in fact) to surmise that it must exist for a reason – in particular […]

Mirrored from http://wiringthebrain.blogspot.com The question of what makes each of us the persons we are has occupied philosophers, writers and daydreamers for millennia but has been open to scientific inquiry over a far shorter time. The answer clearly lies in the brain and, somehow, in how it is “wired” (whether that refers to the amount […]