Emotion research needs you

Jeremy Dean is the author of PsyBlog and also a postgraduate psychology researcher. He’s asking for people to spend 15 minutes completing some online questionnaires as part of a study on emotion.

The project is based at University College London but you can participate over the web.

There’s more information at the link below.

Link to Jeremy Dean’s emotion study.

Mouse-sized neural network created

Despite what the headlines might say, no-one has simulated a mouse brain. What has been created is still quite impressive though.

Scientists from IBM have created an artificial neural network which contains the simulated equivalent of the number of neurons in an actual mouse cortex, but with less synapses.

The mouse cortex contains about 8 million neurons, each of which has an average of 8,000 synaptic connections.

The simulation used the same number of ‘neurons’, but used an average of only 6,300 synaptic connections per brain cell, and each neuron fires about ten times slower than in real life.

Crucially, the simulated neurons are only vague approximations of the actual thing.

This is no reflection on the researchers, but really a result of the fact that we just don’t know enough about how single neurons work to create truly accurate simulations.

Also, the model was made up of simulated neurons of one particular type only to make things a little more straightforward.

Finally, there was no attempt to recreate the ‘architecture’ of the mouse cortex – that is, the division of the model into sections which do different functions, and no attempt to account for the function of non-neuronal brain cells.

The sheer scale of the model is impressive though, and shows that these large scale models are becoming technically feasible.

Previously, the technical restrictions of dealing with the computations and moving the data about quickly enough had not been overcome for a simulation of this size.

The project was run on a BlueGene/L supercomputer to make it possible.

IBM have released a short technical report on the project which is available at the link below.

pdf of report ‘Towards Real-Time Mouse Scale Cortical Simulations’.
Link to Wikipedia page on artificial neural networks.

Golden Guide to Hallucinogenic Plants

Online psychedelic drug archive Erowid has scanned in a copy of a classic guide to hallucinogenic plants of the world and how they are used by native peoples.

The Golden Guide to Hallucinogenic Plants is by pioneering ethnobotanist, Richard E. Schultes.

Ethnobotany is the study of how people make use of plants, and hallucinogenic plants are obviously of keen interest owing to their important place in ritual and religion throughout the world.

The book is sadly out of print and and second hand copies are now collectors items. However, the full version has been scanned in full colour, so you can read it online or download it as one single zip file.

Link to Golden Guide to Hallucinogenic Plants (via BB).

You are not your brain scan!

ABC Radio National’s All in the Mind just broadcast some essential listening with a programme that takes a critical look at the reporting of brain scanning studies and discusses what brain scans actually tell us about human nature.

The panel discussion also covers how cognitive and neuroscience discoveries get translated from lab work to public awareness, and how the core messages might get warped along the way.

The panel members are researchers and science journalists Deborah Blum and Jonica Newby, as well as neuroscientist Fred Mendelsohn.

It’s a rare but important discussion that actually takes a look at how brain scans are used in the media compared to what they actually tell us.

Link to All in the Mind brain scan programme webpage with transcript.
mp3 of programme audio.

Examining the brains of the dead to tackle dementia

The Washington Post has a fascinating article on the work of neuropathologist Dr Bennet Omalu (pictured right) who is researching whether American footballers are more likely to get dementia by examining their brains – after they’ve died.

The technique itself isn’t particularly controversial as the post-mortem study of brain tissue is one of the mainstays of neuroscience research.

It is difficult work, however, as it often involves asking the relatives at the point of death whether the body of their loved one can be examined for medical research, usually involving removing parts and examining them under a microscope.

Omalu thinks that the blows to the head suffered during Americfan football may increase the risk for early onset dementia and claims to have found tell-tale signs in the brain.

The idea that persistent low level head injury might raised the risk of dementia is not particularly new.

There are even some research findings suggesting that late life brain function is worse in ex-footballers and the risk for dementia may indeed by higher.

The Washington Post article is an interesting insight into an essential but difficult type of neurological research.

Link to Washington Post article ‘Brain Chaser Tackles Effects of NFL Hits’.

May’s Nature Reviews Neuroscience free on registration

The May edition of top brain research journal Nature Reviews Neuroscience is available online for anyone who completes the free site registration.

The issue contains a round-up of recent neuroscience news, as well as some in-depth reviews of depth perception, the genetics of nervous system development, olfactory memory in fruit flies, neural cycle cyle regulation and a fantastic article on the epigenetics of psychiatric disorder.

Epigenetics describes the process of how genes actually ‘do their work’.

DNA has two main functions. The ‘template function’ of DNA is to pass on genes through generations and allow different traits to be inherited.

The ‘transcriptional function’ of DNA is to allow these genes to be expressed at appropriate times and places (and not expressed at others) so the work can be done.

Almost every cell in the body has a copy of the DNA and, therefore, all the genes, but there are many types of cells with many diverse functions.

This is because not all genes are transcribed and expressed at once. Genes are expressed selectively.

This allows the body to have a diverse range of differently structured cells, and it allows the same cells to do different work at different times.

In a famous 1998 paper, Kandel noted that the transcriptional function of genes, that determines which proteins are expressed at any particular time, can be regulated by social, environmental and experiential (learning-based) factors.

This is why epigenetics is so important, because it is one way of understanding how genes and the environment interact.

We know that it is possible to inherit a variable risk for mental illness, and that life experiences are likely to combine with this risk to trigger mental illness in some people.

The Nature Reviews Neuroscience article looks at the latest research on how this occurs and how it might be different in various types of psychiatric disorder.

Link to May’s Nature Reviews Neuroscience (via Pimm).
Link to PubMed entry (with full text links) for Kandel’s classic 1998 paper.

Slate special on neuroscience

Slate has just released a special series on the brain – taking a critical look at some of the most recent developments in the field and asking researchers how neuroscience has changed their life.

There’s a wonderful article by developmental psychologist Alison Gopnick on getting past the hype surrounding mirror neurons – which are being used to explain almost every form of human behaviour despite the lack of evidence.

A host of brain researchers note how neuroscience has impacted on their day-to-day life and changes the way they see the world.

Most strikingly, Christof Koch notes that his research into consciousness convinced him to become vegetarian as “mammals can consciously experience the pains and pleasure of life”.

There’s also a few articles on cognitive enhancement: notably, one on the history and myths behind popular ‘brain supplement’ ginkgo biloba and another on neuroplasticity and the new craze for ‘brain training‘ programmes.

Neurotheology, the neuroscience of religious and spiritual experience, also gets a look in with an article examined the development of this new discipline and another on whether technology could induce spritual experiences via the brain.

I have to say, the article on the ‘five biggest neuroscience developments of the year’ is a bit ropey.

For example:

2. The neural alteration of morality. Six people with damage to the ventromedial prefrontal cortex were presented with moral dilemmas (e.g., would you smother a baby to prevent bad guys from finding and killing people in hiding) and were found to be two to three times more willing to kill than people without brain damage. The advertised conclusion is that such willingness to kill is objectively immoral. The feared conclusion is that if brain design determines what’s moral, you can change morality by changing the brain – and once technology manipulates ethics, ethics can no longer judge technology.

In fact, we’ve known for a very long time that brain damage can make people less moral, as the case of Phineas Gage suggested, and modern studies of ‘acquired sociopathy’ have reported.

It’s also interesting that the study in question found patients with ventromedial brain damage were actually more moral in utilitarian terms.

They were less swayed by the normal emotional response to making decisions that required trading off considerations of group welfare against emotionally negative behaviours (for example, having to sacrifice one person’s life to save a number of other lives).

Whether this is less moral, depends on your moral framework.

Generally, though, the series is well worth checking out and has some fascinating insights and commentary.

Link to Slate special series on the brain.