In recent years efforts have been made to analyse the part played by the frontal lobes in the integration of personality. The pioneer work of Bianchi (1922) based on pathological lesions in human subjects, and on experimental bilateral ablations in monkeys, dogs and foxes, still appears to be as true to-day as when originally enunciated. Sherrington (1901) also described the changes following destruction of the frontal lobes. It was noted that such animals lost the power to learn and to enjoy themselves. They had no curiosity, but became restless, hyperactive and easily distracted. Brickner (1936) studied over many years a patient with bilateral frontal lobectomy who showed a diminished ability to synthesize abstract thoughts. Goldstein (1941) found that patients with frontal lobe damage lose their power for abstract thought and this is replaced by concrete behaviour, as shown by object grouping tests and their use of words. Similarly Penfield and Hebb (1940), in a case of extensive lobectomy for an infiltrating oligodendroglioma in an intelligent housewife, described a lack of ability for complex planning, such as is necessary for preparing a meal of several courses. Jefferson (1937) was unable to find any deficiency in cases of unilateral lobectomy. Rylander (1939), on the contrary, after lobectomy for tumours was able to detect changes similar to those found by Goldstein, and in cases with frontal lobe injury he found a lack of social sense. These patients were embarrassingly outspoken, and sometimes showed excessive activity or fatigue. Hebb (1945) concluded that studies on pathological lesions of the frontal lobes were not very helpful, owing to the lack of precision of the lesions due to the uncertain extent of the pathology.