Psychosurgery Flashcards
What is psychosurgery?
a surgical procedure for treating a mentally disordered behaviour. By removing or destroying part of the brain the aim is to eradicate the undesirable behaviour. The term psychosurgery is not used when there is a known physical cause for a problem, such as a brain tumour or epilepsy. This is called brain surgery. Psychosurgery is used to describe the process of removing or destroying functioning parts of the brain in order to bring about a change in behaviour.
How do biological assumptions apply to psychosurgery ?
The biological approach would assume that psychological disorders such as depression, anxiety and schizophrenia have a physiological cause. This approach to therapy is known as the medical model and is based on the view that mental illnesses are like physical illnesses – they have a physical cause, characterised by clusters of symptoms (a syndrome), and therefore can be treated in a physical way. The medical model recommends that a patient should be treated for their mental illness through direct manipulation of their physical bodily processes, for example through altering parts of the brain (psychosurgery).
How do localisation of Bain function apply to psychosurgery?
the idea that certain areas of the brain have different jobs or functions that they carry out. Treating psychological disorders in a physical way involves destroying or removing certain areas of the brain that are thought to contribute to psychological problems such as depression or anxiety.
How do neurotransmitters apply to psychosurgery?
modern methods of psychosurgery involve stimulating areas of the brain which has an effect on neurotransmitters on the brain. Low levels of certain neurotransmitters in the brain are associated with mental disorder for example; low levels of serotonin are linked with depression. If the brain is stimulated and serotonin levels increased, the patient will experience improved mental health.
What are the main components of psychosurgery?
Prefrontal lobotomy, stereotactic and DBS.
Explain a prefrontal labotomy.
a surgical procedure involving selective destruction of nerve fibres. It is performed on the frontal lobe of the brain, an area that is involved in impulse control and mood regulation. Its aim is to alleviate some of the severe symptoms of mental illness As a rule severity of illness was a more important factor than the type of illness, along with the consideration of how dangerous the patient was. Moniz 1930s (Portuguese neurologist) – developed a surgical procedure known as a prefrontal leucotomy. This involved drilling a hole on each side of the skull and inserting an instrument that looked like an ice-pick to destroy the nerve fibres underneath. Moniz later refined his technique by designing a ‘leucotome’, and instrument with a retractable wire loop that could cut into the white matter of the brain and sever nerve fibres. It was hoped that cutting into the nerve pathways that carried thoughts from one part of the brain to the other would relieve patients of their distressing thoughts and behaviours.
Explain stereotactic.
More recently, neurosurgeons have developed far more precise ways of surgically treating mental disorders such as OCD, bipolar disorder, depression and eating disorders that fail to respond to other forms of treatment.
Modern techniques use brain scans, such as MRI scans, to locate exact points within the brain and sever connections very precisely. The procedure is done using an anaesthetic.
Explain OCD.
In OCD for example, a circuit linking the orbital frontal lobe to deeper structures in the brain, such as the thalamus appears to be more active than normal. The bilateral cingulotomy is designed surgically to interrupt this circuit. Surgeons can either burn away tissue by heating the tip of the electrode, or use a non-invasive tool known as a gamma knife to focus beams of radiation at the target site.
In a capsulotomy, surgeons insert probes through the top of the skull and down into the capsule, a region of the brain near the hypothalamus that is part of the circuit. They then heat the tips of the probes, burning away tiny portions of tissue.
Explain DBS.
A possible alternative to psychosurgery is deep brain stimulation (DBS), where surgeons thread wires through the skull. This more modern type of psychosurgery involves no tissue destruction and is thus only temporary. The wires, which remain embedded in the brain, are connected to a battery pack implanted in the patient’s chest. The batteries produce an adjustable high-frequency current that interrupts the brain circuitry involved in, for example, OCD. If it doesn’t work, it can always be turned off.
What is the effectiveness of early psychosurgery?
Lobotomies had a fatality rate of up to 6% and a range of severe physical side effects such as brain seizures and lack of emotional responsiveness (Comer, 2002). Modern psychosurgery is very different, however some of the same objections could still apply.
What is the effectiveness of modern psychosurgery?
Cosgrove and Roche (2001) carried out a general review of research. They reported that a cingulotomy was effective in 56% of OCD patients, and capsulotomy in 67%. In patients with major affective disorder, cingulotomy was effective in 65% and capsulotomy in 55%. However given that the authors claimed that only about 25 people a year are currently treated this way in the US, the sample size is small.
How effective is DBS?
DBS has been found to be effective in patients suffering with severe depression. E.g. Mayberg et al (2005) found that in 4 out of 6 patients with this disorder, striking improvements were noted following treatment involving stimulation of a small area of the frontal cortex.
Explain the appropriateness of psychosurgery.
Psychosurgery has limited uses. Szasz (1978) criticised psychosurgery generally because a person’s psychological self is not something physical and therefore it is illogical to suggest it can be operated on.
Explain the future directions of psychosurgery.
DBS is evolving as a research tool as well as a form of treatment. This is due to the fact that this procedure can provide the researcher with information that other than scanning methods cannot. For example, the EEG is able to tell us when activity in the brain is happening, but not where. By contrast, functional MRI scans (fMRI) does the opposite, it tells us where the activity is but is to slow to pinpoint when. DBS can provide information about both.
Explain the ethical issues.
Valid consent: Patients may not be in the right frame of mind when making the decision to participate in psychosurgery, if someone is suffering from a serious mental health condition they may not be in a position to give valid consent. The question to consider is would they give the same consent if they were in their well state of mind. Furthermore, do they fully understand what will happen, do they know that they are giving permission for the surgeons to inflict permanent damage to their brains.
Irreversible damage: The right to withdraw has gone once surgery has taken place. The patient will have been permanently harmed so therefore you could argue that they are not being protected The therapists and surgeons would argue though, that given their illness there is the possibility that they could harm themselves so therapists would argue that they are actually being protected.
