neurophilosophy
Posts by this author
May 11, 2009
Music can be thought of as a form of emotional communication, with which the performer conveys an emotional state to the listener. This "language" is remarkably powerful - it can evoke strong emotions, and make your heart race or send tingles down your spine. And it is universal - the emotional…
May 4, 2009
Human cultural traits such as language, dress, religion and values are generally said to be passed from one generation to the next by social learning. And in animal species which have language, the same is true; male song birds, for example, learn the songs with which they serenade potential mates…
April 13, 2009
If you look at a waterfall for about 30 seconds, and then shift your gaze to a nearby stationary object, such as a rock or a tree, that object will seem to drift slowly upwards. This well known optical illusion demonstrates a phenomenon called the motion after-effect, which is thought to occur as a…
April 3, 2009
The journey undertaken by newly generated neurons in the adult brain is like the cellular equivalent of the arduous upstream migration of salmon returning to the rivers in which they were hatched. Soon after they are born in the subventricular zone near the back of the brain, these cells migrate to…
April 1, 2009
It is now well established that the adult mammalian brain contains stem cells which continue to generate new neurons throughout life. This discovery, and subsequent research, has transformed the way we think about the brain. It is, for example, known that physical and mental exercise can stimulate…
March 27, 2009
If someone told you that they wanted to have a perfectly good leg amputated, or that they have three arms, when they clearly do not, you would probably be inclined to think that they are mentally disturbed. Psychiatrists, too, considered such conditions to be psychological in origin. Voluntary…
March 24, 2009
Optogenetics is a newly developed technique based on a group of light-sensitive proteins called channelrhodopsins, which were isolated recently from various species of micro-organism. Although relatively new, this technique has already proven to be extremely powerful, because channelrhodopsins can…
March 20, 2009
The way we perceive other people has a big influence on how we interact with them. For example, attractive people are more likely to be perceived as talented than less attractive people, and this so-called "halo effect" is often reflected in our behaviour towards them. Similarly, we tend to favour…
March 18, 2009
Memory has intrigued us for millenia, and is today one of the most active areas of neuroscience research. Much of this research has aimed to understand how memories are laid down, and a picture of how this happens is beginning to emerge. Hundreds of studies published over the past few decades…
March 16, 2009
We all know what it means to be conscious. You are, of course, conscious right now - if you were not, you would be unable to read this. And while you read, you will be conscious of the words on your computer screen; of tactile sensations originating from the mouse you are holding and the chair you…
March 12, 2009
Spatial navigation is a complex mental task which is strongly dependent upon memory. As we make our way around a new environment, we look for easily recognisable landmarks and try to remember how their locations are related in space, so that when we return to it we can negotiate our path.
We know…
March 10, 2009
One of the central dogmas of neuroscience, which persisted for much of the history of the discipline, was that the adult human brain is immalleable, and could not change itself once fully developed. However, we now know that this is not the case: rather than setting like clay placed into a mould,…
March 9, 2009
More than 100 years ago, Sigmund Freud, the father of psychoanalysis, proposed a mechanism called repression, whereby desires and impulses are actively pushed into the unconscious mind. For Freud, repression was a defence mechanism - the repressed memories are often traumatic in nature, but,…
March 3, 2009
Nervous tissue is extremely fragile, and so is very well protected. The brain, which has a jelly-like consistency, is encased in the skull, and is surrounded by cerebrospinal fluid, which acts to cushion it against blows that might cause it to come into contact with the inside of its bony case.…
March 2, 2009
Despite occuring only rarely, amnesia (or memory loss) has featured often in Hollywood films for almost a century. By 1926, at least 10 silent films which used amnesia as a plot device had been made; more recent productions, such as 50 First Dates and Eternal Sunshine of the Spotless Mind, are…
February 24, 2009
Alzheimer's Disease is the most common form of dementia, affecting more than 400,000 people in the U.K. and some 5.5 million in the U.S. The disease has a characteristic pathology, which often appears first in the hippocampus, and then spreads to other regions of the brain. This is accompanied by…
February 21, 2009
These gorgeous stipple-engraved plates come from The Anatomy of the Brain, Explained in a Series of Engravings, by Sir Charles Bell. The book was first published in 1802 and contained 12 plates, 11 of which were printed in colour; these come from an edition which appeared in 1823.
In the…
February 19, 2009
Working memory refers to the process by which small amounts of information relevant to the task at hand are retained for short periods of time. For example, before cellular phones became so ubiquitous, calling someone usually involved first finding the number and then remembering it for a just few…
February 10, 2009
Bones have been big news recently, following the publication of two papers which document remarkable fossil finds. First, a group of palaeontologists led by Phil Gingerich of the University of Michigan described Maiacetus inuus, a primitive whale which lived in the water but gave birth on land, and…
February 9, 2009
Most of us have experienced the vague feeling of knowing something without having any memory of learning it. This phenomenon is commonly known as a "gut feeling" or "intuition"; more accurately though, it is described as implicit or unconscious recognition memory, to reflect the fact that it arises…
February 8, 2009
I have finally jumped on the bandwagon and started to use Twitter. I had avoided it because I couldn't understand why anyone would want to share the mundane details of their life with others, but am now beginning to see how it can be useful, and also to enjoy using it.
If you too are using Twitter…
February 5, 2009
When Sir Francis Galton first described the "peculiar habit of mind" we now call synaesthesia, he noted that it often runs in families. Modern techniques have confirmed that the condition does indeed have a strong genetic component - more than 40% of synaesthetes have a first-degree relative - a…
February 2, 2009
During the first half of the twentieth century, the American psychologist Karl Lashley conducted a series of experiments in an attempt to identify the part of the brain in which memories are stored. In his now famous investigations, Lashley trained rats to find their way through a maze, then tried…
January 27, 2009
In his epic poem Visions of the Daughters of Albion, William Blake asks: "Where goest thou O thought? To what remote land is thy flight?" More than two centuries later, memory remains as one of the enduring mysteries of neuroscience, and despite decades of intensive research using modern techniques…
January 26, 2009
What sensory cues do we rely on during the perception of speech? Primarily, of course, speech perception involves auditory cues - we pay close attention to the sounds generated by the speaker. Less obviously, the brain also picks up subtle visual cues, such as the movements of the speakers mouth…
January 20, 2009
Delusions are pathological beliefs which persist despite clear evidence that they are actually false. They can vary widely in content, but are always characterized by the absolute certainty with which they are held. Such beliefs reflect an abnormality of thought processes; they are often bizarre…
January 19, 2009
The brains of vertebrates are asymmetrical, both structurally and functionally. This asymmetry is believed to increase the efficiency of information processing - one hemisphere is specialized to perform certain functions, so the opposite is left free to perform others. In the human brain, for…
January 13, 2009
The unique capabilities of the human hand enable us to perform extremely fine movements, such as those needed to write or to thread a needle. The emergence of these capabilities was undoubtedly essential in human evolution: a combination of individually movable fingers, opposable thumbs and the…
January 12, 2009
The Boston Globe has a cool infographic by Jonah Lehrer and Javier Zarracina, describing five simple ways in which sensory perception can be altered using everyday objects. These include the Ganzfeld procedure, a mild sensory deprivation technique which leads to visual or auditory hallucinations;…
January 9, 2009
The familiar buzzing sound made by a mosquito may be irritating to us humans, but it is an important mating signal. The sound, produced by the beats of the insect's wings, has a characteristic frequency called the "flight tone"; when produced by a female, it signals her presence to nearby males,…