Psychosurgery and the limbic system

Abstract

Summary The limbic system can be considered to consist of a central ‘core’ from which three well-defined circuits emerge. These are the Papez or medial circuit, the basolateral circuit and the defence reaction circuit. The functions of the primitive limbic brain are modulated by a higher order control—the frontal lobe. Emotional responses and physiological changes have been obtained by stimulation of fronto-limbic pathways and limbic circuits and these have been used for location of target sites in psychosurgery. For the relief of intractable depression and anxiety, lesions are generally made in the lower medial quadrant or posteroorbital part of the frontal lobe, where there is a concentration of fronto-limbic connections. In primary obsessional neurosis lesions at this site produce less satisfactory results, but these illnesses may be helped by lesions in the cingulate gyrus, which is part of the Papez circuit. Patients with epilepsy and aggressive outbursts may respond to temporal lobotomy, or to operations, such as amygdalotomy, where lesions are placed in the defence reaction circuit.

Personality correlates of sphenoidal EEG-foci in temporal lobe epilepsy

“…The more pronounced personality change in patients with mediobasal focus is hypothesized to be due to dysfunction of the limbic structures involved in emotional expression and epilepsy (e.g. Kelly 1973, Heath et al 1980. Our third main finding was that patients with a left-sided focus tended to be more aggressive and emotionally labile than patients with an exclusively right-sided EEG focus.…”

Studies of endocrine activity, plasma tryptophan and catecholamine excretion on psychosurgical patients

“…It is difficult to suggest explanations for the marked post-operative reduction in noradrenaline output, which is unlikely to be a non-specific autonomic response to the stress of surgery because adrenaline showed a rise, especially in the case of the male patients, and urinary cortisol, as reported earlier, also tended to rise post-operatively in most cases. There remains the possibility that a change in noradrenaline metabolism is brought about by the ventromedial quadrant lesion in depressed patients and in this connection it is of interest that psychosurgery has been postulated to have effects on the limbic system ( Kelly (1973), Nauta (1973)). It appears that the fall in output may be related to improvement due to the operation because the reduction was significantly greater at 2 weeks post-operatively for those who, 1 year after, were found to have responded well.…”

Tratamiento quirúrgico de la anorexia nerviosa resistente al tratamiento médico

“…En la mayoría de ellos, los pacientes ganan peso en el contexto de la mejoría de otros síntomas. Sin embargo, la heterogeneidad y falta de datos en cuanto a la selección de pacientes, el seguimiento y las medidas de resultado hacen que se deban interpretar estos resultados con cautela (29,30).…”

“…El término "lobotomía" se refiere a resección de las vías, mientras que el término "leucotomía" se refiere a la transección de forma selectiva de las vías (29).…”

“…Para ello, hay que implantar un marco metálico en la cabeza del paciente, en el cual existen unas coordenadas tridimensionales externas, que detallan de forma muy precisa su correspondencia con estructuras internas cerebrales. El desarrollo de las técnicas estereotáxicas ha supuesto un avance importante en la neurocirugía funcional (29,37,38).…”