Author: vaughanbell

The New York Times has an article on people who experience musical hallucinations.

This form of hallucination is interesting, because they are often the only unusual experience a person will have, unlike in psychosis, where hallucinations may be part of a range of anomalous beliefs and experiences.

Patients reported hearing a wide variety of songs, among them “Don’t Cry for Me Argentina” and “Three Blind Mice.” In two-thirds of the cases, the music was religious; six people reporting hearing the hymn “Abide With Me.” Dr. Aziz believes that people tend to hear songs they have heard repeatedly or that are emotionally significant to them.

Neurologist Tim Griffiths has been brain scanning people who experience these hallucinations. He has found that similar areas of the brain are active when a person is hallucinating music, compared to when they are actually listening to music, except for an area called the primary auditory cortex. This is the area of the brain just behind the ears, and is responsible for the initial processing of sounds.

Interestingly, musical hallucinations are often triggered by deafness.

These music-processing regions may be continually looking for signals in the brain that they can interpret, Dr. Griffiths suggested. When no sound is coming from the ears, the brain may still generate occasional, random impulses that the music-processing regions interpret as sound. They then try to match these impulses to memories of music, turning a few notes into a familiar melody.

Link to reg free New York Times article on musical hallucinations (originally via BrainBlog).

UPDATE: There’s a good piece by Carl Zimmer on musical hallucinations here.

Science News has a major article discussing sleep paralysis, the state in which a person can wake, but remains in the paralysed state used to stop movements during dreaming.

Sleep paralysis, sometimes called ‘awareness during sleep paralysis’, to distinguish it from the normal muscle inhibiting function of REM sleep, is now attracting a substantial amount of research.

One paper by researchers Katharine Holden and Chris French (PDF) even suggested that some ‘alien abduction’ experiences may be due, in part, to terrifying sleep paralysis episodes.

Little is known, however, about the exact brain mechanisms which control sleep paralysis (although parts of the brain stem are known to be important) meaning it is has traditionally been difficult to make educated guesses about why paralysis sometimes remains after waking.

Link to Science News article ‘Night of the Crusher’

ABC Radio’s All in the Mind has a special on the neuroscience of orgasm and the use of brain scanning in understanding this complex event.

The programme focuses on work being carried out by a Dutch team, who are now one of a number of research centres who are studying the neuroscience of orgasm and sexual response after it has been neglected for so many years.

Their work has been reported on Mind Hacks before (here and here) but this includes an interview with the lead researchers and commentary from a number of other experts.

mp3 or realaudio of programme audio.
Link to programme transcript.

American TV channel PBS have a lush website to accompany their series ‘The Secret Life of the Brain‘, with many of the video segments online.

They have an episode by episode guide, that examines the development of the brain from birth, through the process of growing up, and into adult years and old age.

Plenty of supplementary material has also been made exclusively for the web, including a Flash driven 3D brain atlas, a guide to current brain scanning technologies and an illustrated history of brain science.

Link to PBS website to accompany ‘The Secret Life of the Brain’.

Wired has a feature article online about research into the neuropsychology of female orgasm and the approach of current lab based studies.

This sort of research is important, because so little is known about the neural basis of sexual function. In particular, the article describes some intriguing findings, that not all nerves involved in genital arousal route through the spinal cord, some may go more directly to the brain.

Unfortunately, the article frames much of the research in terms of drug development for sexual dysfunction, which is so often the case in these sort of pieces. This is perhaps because much of the research may be funded by drug companies.

This shouldn’t mean however, that journalists should uncritically reproduce the assumptions that these sources promote – mainly that sexual dysfunction is defined in terms of someone else’s arbitrary criteria, and is best treated by (usually expensive) pharmaceuticals.

Link to Wired article ‘The Coming Boom’.
Link to an alternative take on sexual neuroscience by sex psychologist Petra Boyton.

Open-access science journal PLoS Biology reports on research looking at how the brain handles object recognition among the clutter of the everyday visual world.

Researchers, led by neuroscientist Zoe Kourtzi, asked participants to detect objects hidden in various background images, whilst being scanned in an fMRI scanner.

“The authors found that subjects demonstrated an increased number of correct responses for shapes they encountered during the training sessions, regardless of the type of background the shapes were presented on. By contrast, the fMRI responses differed dramatically, depending on whether the surroundings made the shapes easy or difficult to detect.”

“These results demonstrate that the ability to learn to detect novel shapes is independent of the degree of difficulty, but suggest that the brain employs different mechanisms of perceptual learning depending on whether the objects stand out from their surroundings, or are obscured by them.”

Link to summary of study.
Link to full-text of study.