Psychosurgery

Psychosurgery Psychosurgery-the use of surgery on the brain to treat psychological functions. Egas Moniz pioneered the technique and it was developed by Walter Freeman. Based on 2 observations : A lab chimp pacified by operation on frontal lobes. Tumour operation on a human frontal lobe without causing intellectual damage.

Techniques Leucotomy A narrow device was inserted (via holes made in the skull) into the frontal lobe. The blade of the leucotome was then extended and rotated to lesion a core of tissue. This was repeated several times to destroy pieces of prefrontal cortex.

Techniques Transorbital lobotomy Used a special knife called an ‘ice pick’. Inserted under the eye lid and into the back of the eye socket. This was used to break through the skull into the brain & was moved around to destroy connections between the prefrontal area & other brain areas. This was repeated on both hemispheres.

Why used? Used on patients who were emotionally unstable and violent & did not respond to other forms of therapy. It generally had the effect of relieving emotional distress & anxiety and calmed the patient down. As a result the surgery became common. Tooth & Newton (1961) reported that more than 10,000 operations were performed in the UK.

Side effects Such procedures are now rare because of their severe side effects. Problems include: Changes in personality. Lethargic, apathetic, irresponsible, socailly withdrawn. Lacked ability to plan their own behaviour.

Evaluation Evidence for which lobotomies were based was very limited. Findings from the chimpanzee may not be relevant to humans due to brain structure & function. Findings from the human case may not be generalisable, as the medical reason for the lobotomy was a physical not a psychological one.

Evaluation The rapid growth of the technique was based on its use for reducing stress & making difficult individuals more manageable for staff in institutions. This is unethical. Moniz & Freeman claimed high success rates for their operations. This was supported by Pippard(1955) who found worthwhile or good results for 62% of leucotomised depressive patients & good results with 50% of those with affective disorders. In 95% of these cases Pippard reported no more than slight personality changes. However, many other sources reported severe side effects and original procedures were abandoned.

Current Procedures Bilateral cingulotomy is now occasionally performed. Used to help very depressed patients, sufferers of OCD & to reduce pain in cancer patients. This techniques uses very accurate MRI to assist surgeons to identify the exact location of the area to be lesioned. A fine electrode destroys the tissue directly.

Evaluation of current procedures Mixed evidence. Seems to reduce pain, it does not appear to affect the pain threshold. Similar side effects. Cohen et al (1999) compared the pre-operative performance of 12 cingulotomoy patients being treated for chronic pain with 20 control patients also with chronic pain. Over 60% of the cingulotomy patients reported less pain post operatively and most required less medication to control their pain. However, Cohen et al found some consistent post-operative problems. On average these patients lacked the ability to spontaneously initiate responses (such as verbal responses) & showed deficits in attention compared with the controls.

Evaluation of current procedures Investigating the use of cingulotomy for OCD, Baer et al (1995) followed 44 patients. They found the treatment to be effective in 32% of cases and partially in a further 14%. Some patients reporter side effects including seizures. Mashour et al(2005) suggests that psychosurgery is a much safer & ethically sound approach because of the usefulness of modern elecrical brain-stimulation techniques.