Under the Microscope: Most people have heard of Sigmund Freud (1856-1939), the Austrian psychiatrist and originator of psychoanalysis. His pioneering work introduced the concepts of the id, ego and superego.
Freud's ideas and the analyses and treatments he initiated were widely accepted until the 1950s, but by the 1980s most of his notions were considered to be outdated. However, recent neurological finding are beginning to validate Freud's general framework of how the mind works. Freud's recent rehabilitation is described by Mark Solms in Scientific American (May 2004).
Freud proposed that our basic motivations are largely hidden in our subconscious minds but are actively prevented from reaching our conscious minds by repressive forces. We see ourselves as civilised persons and the ego part of our mind rejects unconscious drives coming from the id that might cause behaviour incompatible with our perception of ourselves. The unconscious drives are largely infantile fantasies, unbridled passions and aggressive and sexual urges. In Freud's model the superego represses instinctual drives coming from the id and prevents them from interfering with rational thought carried out by the ego.
Freud explained mental illness as a failure of repression of unconscious drives, allowing them to dictate some voluntary behaviour. Psychotherapy was designed to follow symptoms of mental disturbance back to their unconscious roots, to rationally judge these roots and thereby bleed off their compulsive power.
As neurology and neuroscience developed during the 20th century the psychoanalytical approach was gradually replaced by a biological approach and drug treatment. The idea gained currency that the mind consists of nerve-cell chemistry and that mental illness is a reflection of unbalanced chemistry.
However, recent neurological mapping of the brain generally correlates with Freud's 1933 model of the mind. Instincts and drives are located in the core brain stem and limbic system - corresponding to Freud's id. The ventral frontal brain region, controlling selective inhibition, the dorsal frontal region, controlling self-conscious thought, and the posterior cortex, representing the outside world, correspond to the ego and the superego.
Freud believed that our unconscious mental processes mostly determine our everyday thoughts and feelings. Recent findings confirm the power of the unconscious. The behaviour of patients who are not able to consciously remember events that happened after damage to memory-coding parts of their brains has been shown to be influenced by the "forgotten" events.
Recent research has also discovered unconscious memory systems that mediate emotional learning. A nerve pathway under the conscious cortex of the brain carries perceptual information to the primitive brain stem where fear responses are generated. This pathway bypasses the hippocampus area of the brain where conscious memories are generated. Current events can therefore trigger unconscious memories of past emotional events and cause conscious feelings that seem irrational, e.g. "bald men make me feel unsettled".
Recent research has also shown that, during the first two years of life, brain structures that form conscious memories are not active, explaining what Freud called "infantile amnesia". Our earliest memories are not forgotten but we cannot consciously remember them. However, these unconscious memories can affect adult behaviour and feeling. Early experiences, particularly between mother and baby, affect brain development in ways that shape adult personality and mental health.
There is also recent evidence that our minds repress unpalatable information. Damage to the right brain region of "anosognosic" patients makes them unaware of serious physical defects, e.g. a paralysed limb. In one study the right brain of such a patient was stimulated and she suddenly became aware that her left arm had been paralysed since her stroke eight days previously. She had unconsciously registered her paralysis for eight days, despite consciously denying during these days that there was a problem.
Freud also believed that the repressed part of the unconscious mind operates on a different principle to the "reality principle" that operates in the conscious ego. The unconscious thinking disregards logic and is wishful, operating on a "pleasure principle". Recent research has shown that damage to the inhibitory structures of the brain (the repressing superego) releases wishful irrational modes of mental functioning.
Not everyone is happy about the revitalisation of Freudian theories. Many neuroscientists have distasteful memories of the gospel of Freudian theory they were exposed to in their training and of the slow ambiguous outcome of much psychoanalysis based on this theory. However, if Freud had valuable insights into the mind, these insights cannot be ignored.
Finally some quotations from Sigmund Freud:
"Anatomy is destiny."
"The interpretation of dreams is the royal road to a knowledge of the unconscious activities of the mind." William Reville is associate professor of
biochemistry and director of microscopy at University College Cork