We studied six patients in whom colloid cysts had been removed surgically from the third ventricle. The patients were selected simply by availability for the study, not on grounds of clinically diagnosed amnesia or its absence. The outcomes of operation ranged from one patient who had postoperatively resumed a normal life without complaint of memory disorder at any stage, through four who complained of memory disorder since operation, to one who was so severely amnesic as to require constant supervision. Each patient was given psychometric tests of memory, and was also scanned by magnetic-resonance imaging. One of us examined the six scans and assessed the extent of damage to the fornix, and any other brain damage, in ignorance of the outcomes of the psychometric tests. The fornix in the right hemisphere had been destroyed in all six cases, and all showed evidence of moderate or severe impairment in nonverbal memory. The fornix in the left hemisphere was intact in only one patient; this was the patient who had resumed a normal life without complaint of memory disorder. The left fornix was damaged with some sparing in one further patient, and the remaining four patients showed destruction of the fornix in the left as well as in the right hemisphere. The severity of impairment in verbal memory in these six cases was related to the severity of the damage to the left fornix. No other evidence of brain damage appeared to be systematically related to memory ability. These results add to the evidence that bilateral fornix damage produces amnesia, and that sparing of the left fornix alone is sufficient to ensure a more favourable outcome.

Summary:Purpose: To evaluate prospectively patient's aims for epilepsy surgery as previously outlined theoretically by Taylor et al. (Epilepsia 1997;3:625-30).Methods: Ninety-three consecutive patients were interviewed by a psychiatrist as part of their evaluation for epilepsy surgery. Open-ended questions about the patient were asked, and carers' aims or ambitions for change as a result of putative relief of seizures were elicited. The interviewer aimed to obtain a maximum of five aims for later follow-up purposes. These questions were part of an extensive psychiatric interview that is described.Results: The aims of 69 patients or carers were analyzed. The 204 statements of aims were grouped into 59 categories initially. The five most frequently cited constituted 50% of all the aims listed. These aims were desire for work, driving of motor vehicles, independence, socializing, and freedom from drugs. The patients rarely identified a desire for improvement in cognitive functioning as an aim for epilepsy surgery. A final analysis into six categories showed that changes in social process predominated, even over changes in personal behavior. Conclusions:The social and personal aims to accompany relief of epilepsy identified by patients are consistent with the literature on psychosocial adjustment to epilepsy.

The processes of error awareness and sustained attention were investigated in 18 traumatic brain injury (TBI) individuals and 16 matched control participants. In Experiment 1, we found that: (1) in comparison to controls, TBI participants displayed reduced sustained attention and awareness of error during the Sustained Attention to Response Task; (2) degree of error awareness was strongly correlated with sustained attention capacity, even with severity of injury partialed out; and (3) that error feedback significantly reduced errors. We replicated the finding of a correlation between error awareness and sustained attention capacity in Experiment 2 with a separate sample of 19 TBI participants and 20 controls. We conclude that TBI leads to impaired sustained attention and error awareness. The finding of a significant relationship between these two deficits in TBI suggests there may be a link between these two processes. Feedback on error improves sustained attention performance of control and TBI participants.

To investigate possible distinct contributions of different temporal-lobe structures to odour identification, the University of Pennsylvania Smell Identification Test was administered monorhinally to seizure-free patients who had undergone one of three types of temporal-lobe resection practised in three different institutions for surgical treatment of epilepsy. The resections were neocorticectomy (Dublin), selective amygdalohippocampectomy (Zurich), or anterior temporal-lobe resection with encroachment on amygdala and hippocampus (Montreal). Resections, analysed from MRI scans, showed unexpected encroachment on medial structures in most patients of the neocorticectomy groups, and largest amygdala and hippocampal resections in the amygdalohippocampectomy groups. Impaired odour identification was observed in all patient groups, irrespective of surgical approach, with greatest impairment in the nostril ipsilateral to the resection. The finding of deficits in all three surgical groups suggests that damage in the anterior temporal area, perhaps in piriform cortex, is sufficient to disrupt performance on this task; it may be that function is disrupted in the medial temporal-lobe region by disconnection when the periamygdaloid area is damaged, even when amygdala and hippocampus are left intact. An alternative explanation for our results is that damage in any one of these areas disrupts a complex network involving several distinct temporal-lobe structures.

We report the results of a long-term follow-up study of 50 patients who underwent removal of temporal neocortex with preservation of deeper limbic structures as surgical therapy for intractable temporal lobe epilepsy. The follow-up period ranged from 3 to 15 years. Preoperative EEG investigations were based on interictal discharges alone. Three factors were predictive of a good outcome: (a) A clear unilateral anterior-midtemporal focus (p less than 0.01), (b) stereotypical onset of temporal lobe seizure (p less than 0.005), and (c) greater volume of tissue removed at operation (p less than 0.05). Overall results showed that 62% of patients experienced an outcome of "cure" or "almost cure," as classified according to a modified version of Crandall's criteria (Crandall's I and II). Those who experienced a significant reduction in seizures but who continued to have intractable epilepsy (Crandall's III) were not considered to have had a good result. Overall outcome compares favorably with other that of centers using different surgical approaches and indicates that neocorticectomy is a suitable procedure in a highly selected population even when limited resources are available.