Shelley has written a nice summary of the neuroscience of attention deficit hyperactivity disorder (ADHD). As its name suggests, ADHD is characterized by inattention and hyperactivity. This is often accompanied by forgetfulness and an inability to control impulses. ADHD is a developmental disorder that is believed to be neurological in nature. It presents at an early age and persists into adulthood in about 60% of cases. The condition has proven to be highly controversial in recent years. Some believe that we are too quick to diagnose it, and that children are being over-medicated. Others…
"What is matter? Never mind. What is mind? Never matter." So says Homer, in one episode of The Simpsons. And although I'm not an adherent of Homerian dualism, the show is still my favourite thing on television. I think it's sheer genius. The Simpsons often contains science-based jokes and references to evolution, cosmology and particle physics. In one episode, for example, Homer enters a parallel universe through a wormhole; another features Stephen Hawking, who Homer refers to as "the wheelchair guy". One of my favourite episodes is Lisa the Sceptic (Season 9, Episode 8) in which Lisa…
The New York Times has an obituary of Albert Ellis, a highly innovative psychotherapist who died yesterday at the age of 93.  In the 1950s, Ellis broke with tradition by rejecting the theories of Sigmund Freud, which were widely used at the time. As an alternative, Ellis developed a method called Rational Emotive Behaviour Therapy (REBT), which involved encouraging his patients to alter their behaviour by focusing on current events in their lives. This new method, along with that developed by Aaron T. Beck, would later form the basis of cognitive behaviour therapy.
I received this email yesterday: Hello, I just read your post [on augmented cognition] and found it intriguing. I have been experimenting with a nutritional supplement for the past several years which was designed to treat bi-polar disorder (and it works amazing well for that purpose according to all the researchers who have studied it) and have found my capacity to hold way more information (and not go crazy) and maintain my calmness under pressure is greatly expanded. Some of the rat research neuro-anatomist guys have regrown frontal cortexes in lobotomized rats fed the product and in…
LOBOTOMY (from the Greek lobos, meaning lobes of the brain, and tomos, meaning cut) is a psychosurgical procedure in which the connections the prefrontal cortex and underlying structures are severed, or the frontal cortical tissue is destroyed, the theory being that this leads to the uncoupling of the brain's emotional centres and the seat of intellect (in the subcortical structures and the frontal cortex, respectively). The lobotomy was first performed on humans in the 1890s. About half a century later, it was being touted by some as a miracle cure for mental illness, and its use became…
The term 'Rashomon effect' is often used by psychologists in situations where observers give different accounts of the same event,and describes the effect of subjective perceptions on recollection. The phenomenon is named after a 1950 film by the great Japanese director Akira Kurosawa. It was with Rashomon that Western cinema-goers discovered both Kurosawa and Japanese film in general - the film won the Golden Lion at the Venice Film Festival in 1951, as well as the Academy Award for Best Foreign Language film the following year. Rashomon is an adaptation of two short stories by Akutagawa…
London City Skyline, 2006, by Stephen Wiltshire.  The neurologist Oliver Sacks, who devotes a chapter to Wiltshire in his 1995 book An Anthropologist on Mars, describes first meeting the autistic artist in a short article from the New York Times: When I first met Stephen in 1988, I was intrigued by the silent, withdrawn boy, who was clearly autistic. He seemed without much language until he put pen to paper. And then there were these wonderful drawings, prodigious in powers of memory and detail, beautiful in draftsmanship, full of humor, vitality and charm, so that one felt a complete…
Since a number of other ScienceBloggers have posted lists of science websites for kids (Science sites for kids by Karmen; Online sources for hands-on chemistry for kids by Janet; Cool science sites for kids by Zuska; and Brain science is child's play by Sandra), I thought I'd share this cool practical activity for a lesson about microbes. The activity is designed for schoolchildren at Key Stage 3 (11-year-olds); I gave it a go during my short time as a secondary school science teacher, and thought it was quite effective. Aim To demonstrate how colds can spread from person to person by…
We live in a time in which we are overwhelmed by information obtained from multiple sources, such as the internet, television, and radio. We are usually unable to give our undivided attention to any one source of information, but instead give 'continuous partial attention' to all of them by constantly flitting between them. The limitations of cognitive processes, particularly attention and working memory, place a ceiling on the capacity of the brain to process and store information. It is these processes that some researchers are aiming to enhance with augmented cognition, an emerging field…
This beautiful illustration comes from a textbook called Cerrahiyetu'l Haniyye (Imperial Surgery) by Serefeddin Sabuncuoglo (1385-1470), who lived and practised medicine in Amasya in northern Anatolia. Sabuncuoglo's book, which was published in 1465, is the first illustrated textbook of surgery. It contains several sections devoted to the treatment of psychiatric conditions. The illustration above depicts the use of cauterization (the burning of small areas of tissue) to treat various neuroses.  (Found via this post at Mind Hacks)
The Angry Toxicologist has just joined ScienceBlogs, so go and say hello. ScienceBlogs also has a Cheerful Oncologist, so I'm wondering who'll be next to join their ranks. Will it be a disgruntled pharmacologist? A despondent dermatologist? Or pherhaps an exultant gynaecologist?
That the removal of an entire hemisphere of the brain can be performed with little or no noticable changes in behaviour is a demonstration of the remarkable adaptability of the human brain. This procedure, known as a hemispherectomy, is a drastic measure taken to treat severe and intractable epilepsy. If you think it incredible that someone with only half a brain can function normally, then you won't believe this story from Yahoo News: A man with an unusually tiny brain managed to live an entirely normal life despite his condition, caused by a fluid buildup in his skull, French…
Nerve cells are excitable. At rest, they are said to be polarized; the cell membrane separates the negatively and positively charged ions, so that the inside of the membrane is negatively charged with respect to the outside. In response to a stimulus, nerve cells produce action potentials, which are generated by the rapid movements of ions (negatively or positively charged atoms) across the nerve cell membrane. These ion fluxes lead to depolarization, or a transient reversal of the membrane voltage - the inside of the membrane becomes positively charged, and vice versa. The action potential…
How the brain interprets complex visual scenes is an enduring mystery for researchers. This process occurs extremely rapidly - the "meaning" of a scene is interpreted within 1/20th of a second, and, even though the information processed by the brain may be incomplete, the interpretation is usually correct. Occasionally, however, visual stimuli are open to interpretation. This is the case with ambiguous figures - images which can be interpreted in more than one way. When an ambiguous image is viewed, a single image impinges upon the retina, but higher order processing in the visual cortex…
BioMed Central has just launched Open Access and the Developing world, a portal that focuses on the benefits of open access to scintific and medical literature for developing countries.
The world's most advanced prosthetic hand is now available commercially for about US$18,000. The device is controlled by the electrical signals generated by the muscles in the arm. It has independently movable digits, much like Ambroise Pare's earlier model.
Soon after the discovery of the neuron as the basic functional unit of the nervous system, a model of how nerve cells function emerged. According to this model - the neuron doctrine - the cell body integrates nervous impulses received by the dendrites, and generates an output, in the form of a train of impulses with a specific pattern, which is propagated along the axon. When these impulses reach the nerve terminal, they elicit the release of neurotransmitters, which diffuse across the synapse and bind to receptors embedded in the dendrite membrane of the adjacent cell. This model soon…
There have been no less than three different stories about orchids in the news during the past week. This hammer orchid, which was discovered in southwestern Australia only recently, evolved to resemble a female wasp, thus seducing males of the species into pollinating it. These extremely rare ghost orchids were spotted growing high up in an old cyprus tree in Florida. And finally, the Yosemite bog-orchid, which has just been rediscovered and reclassified as a species in its own right, emits an odour of sweaty feet to attract insects. Isn't nature wonderful?
The French anatomist, anthropologist, and surgeon Pierre Paul Broca (1824-1880) is best remembered for his descriptions of two patients who had lost the ability to speak after sustaining damage to the left frontal lobe of the brain. Broca's observations of these patients, and the conclusions he reached after his post-mortem examinations, would lead to major advances in the understanding of the brain, and laid the foundations for modern neuropsychology. In 1859, Broca founded the Societe d'Anthropologie de Paris. Two years later, several heated debates had arisen there: one was about the…
Nesziah (1995), by Mathew Ritchey, at ArtBrain.org.