Memory

Neurophilosophy

Category archives for Memory

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 that spatial…

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, the brain remains…

Brain mechanisms of Freudian repression

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, although hidden, they continue to exert an effect on behaviour. Many…

Amnesia in the movies

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 therefore part of a…

Reading the contents of working memory

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 seconds by repeating it to oneself…

The neurological basis of intuition

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 from information that was not attended to,…

Tracing memories

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 to erase the memory trace…

R.I.P. H.M.

The amnesic patient known as H.M., who is the best known case study in neuropsychology, has died, at the age of 82. H.M., whose full name has now been revealed as Henry Gustav Molaison, lost completely the ability to form new memories following a radical surgical procedure to treat his severe and intractable epilepsy. The…

Memories are made of molecular motors

Learning and memory are widely thought to involve long-term potentiation (LTP), a form of synaptic plasticity in which a neuron’s response to the chemical signals it receives is enhanced. This leads to a strengthening of the neuronal circuit, so that the memory encoded in the circuit can persist for long periods of time. One of…

Erasing memories

Erasing memories has long been a popular plot device for Hollywood scriptwriters. In the 2004 film Eternal Sunshine of the Spotless Mind, for example, Jim Carrey and Kate Winslet play a separated couple who undergo a radical treatment in order to abolish every trace of the relationship from their brains. The ability to erase memories…