Scan patterns during the processing of facial identity in prosopagnosia.

The scan patterns of ocular fixations made by prosopagnosic patients while they attempt to identify faces may provide insights into how they process the information in faces. Contrasts between their scanning of upright versus inverted faces may index the presence of a hypothesized orientation-dependent expert mechanism for processing faces, while contrasts between their scanning of familiar versus novel faces may index the influence of residual facial memories on their search for meaningful facial information. We recorded the eye movements of two prosopagnosics while they viewed faces. One patient, with acquired prosopagnosia from a right occipitotemporal lesion, showed degraded orientation effects but still with a normal distribution of fixations to more salient facial features. However, the dynamics of his global scan patterns were more chaotic for novel faces, suggesting degradation of an internal facial schema, and consistent with other evidence of impaired face configuration perception in this patient. His global scan patterns for famous faces differed from novel faces, suggesting the influence of residual facial memories, as indexed previously by his relatively good imagery for famous faces. The other patient, with a developmental prosopagnosia, showed anomalous orientation effects, abnormal distribution of fixations to less salient regions, and chaotic global scan patterns, in keeping with a more severe loss of face-expert mechanisms. The effects of fame on her scanning were weaker than those in the first subject and non-existent in her global scan patterns. We conclude that scan patterns in prosopagnosia can both reflect the loss of orientation-dependent expert mechanisms and index the covert influence of residual facial memories. In these two subjects the scanning data were consistent with other results from tests of configuration perception, imagery, and covert recognition.

A comparative study of mismatch negativity (MMN) in epilepsy and non-epileptic seizures.

This study investigated mismatch negativity (MMN) differences between subjects with non-epileptic seizures (NES), subjects with epilepsy, and healthy controls. Event-related potentials (ERPs) were obtained from 14 patients with NES, 15 patients with epilepsy and 16 healthy control subjects. A conventional MMN procedure was used with a random sequence of 12% deviant tones (922 Hz) and 88% standard tones (1000 Hz). Subjects were instructed to ignore the tones delivered through headphones whilst reading a book. Significant differences in distribution of the mismatch negativity (MMN) in patients with NES compared to controls were obtained (F3, p

Quality of life after vagus nerve stimulation for intractable epilepsy: is seizure control the only contributing factor?

We assessed the impact of vagus nerve stimulation on a cohort of patients with intractable epilepsy. A 1-year prospective trial of vagus nerve stimulation for intractable epilepsy was done in 26 patients. Seizure frequency, anti-epileptic drugs, and quality of life were assessed using QOLIE-89, ELDQOL, and a Likert scale of impact of treatment. Seizures were reduced by more than 50% in 19% of the patients, by less than 50% in 46%, and were unchanged in 35% of them. Antiepileptic drugs were reduced in 43% of the patients. There was a significant improvement in the mean overall QOLIE-89 score and other measures of quality of life, but these did not correlate with changes in seizure frequency. Subjective improvement occurred in 84% of the patients. The quality of life improves in some patients following vagus nerve stimulation for intractable epilepsy. The favorable effects of this treatment may be attributable to additional factors besides seizure control which in this study was modest.

Pseudoseizure manifestations in two preschool age children.

We report two patients with epilepsy with pseudoseizures at age 6 years. Both presented with intractable staring spells. Pseudoseizures were provoked and aborted by suggestion, leading to the diagnosis. In both patients, evidence of a neuropsychological disturbance was later found and psychotherapy started. Monitoring of intractable staring episodes is recommended prior to escalating antiepileptic drug levels or resorting to polytherapy. In addition, differentiation from other non-epileptic phenomena is necessary to initiate proper therapy.

Effect of chronic electrical stimulation of the centromedian thalamic nuclei on various intractable seizure patterns: II. Psychological performance and background EEG activity.

We studied the effect of electrical stimulation of centromedian thalamic nuclei (ESCM) on seizure control and paroxysmal EEG activity in 23 patients. We report the effect of chronic ESCM on psychological performance and background EEG activity of patients with various intractable seizure patterns. In each patient, a simple specifically designed neuropsychological scales (one for adults and one for children) was administered at the end of the baseline (BL), ESCM, and poststimulation (Post) periods; and 14 consecutive EEG recordings during these periods were performed to determine the degree of neuropsychological improvement and the temporal course of EEG changes. A significant increase in psychological scores and the number of background EEG waves per 10 s was noted in groups A (generalized tonic-clonic seizures, GTC), C (complex partial seizures, CPS), and D (generalized tonic seizures) and the total group of patients from BL to ESCM and from BL to Post periods. Group B patients showed a substantial increase (partial motor seizures) during the same periods. Improvement on psychological performance correlated better with age and baseline degree of deterioration than with the nature of the particular psychological improvement in any given subtest. The improvement in EEG background rhythm was most noticeable at the end of ESCM and at the beginning of the Post periods. Complete normalization of neuropsychologic scores and EEG rhythms was rare, but improvement was significant for both. Psychological scores increased from BL 14 +/- 2 to ESCM 21 +/- 2 and Post 23 +/- 2 (normal expected 26), and EEG background rhythm increased from BL 42 +/- 2 to ESCM 62 +/- 2 and Post 54 +/- 2 EEG waves/10 s. (normal expected > 80).

Effects of TJ-960 on Sternberg's paradigm results in epileptic patients.

OBJECTIVES: This study is aimed at investigating the effects of TJ-960 on cognitive function in epileptic patients. Sternberg's paradigm was used to examine the change in cognitive function, especially short-term memory, resulting from administration of TJ-960, along with the effects of the drug on seizures. SUBJECTS: The subjects of this investigation were 26 epileptic outpatients (14 males and 12 females; average age: 35 +/- 11 years old) of the Saitama Medical School Hospital, the Tokyo Medical and Dental University Hospital and the Tokyo University Hospital. The controls were 17 other epileptic outpatients (12 males and 5 females; average age: 40 +/- 12 years old) of the same hospitals. METHODS: The subjects were administered 7.5 g of TJ-960 per day for 8 weeks in addition to their previous medications. Immediately before the beginning of drug administration, and again after 8 weeks of administration, they were examined, using Sternberg's paradigm. The controls were examined at intervals of 8 weeks in the same manner as the subjects (i.e., no change in regimen). RESULTS: After 8 weeks of treatment with TJ-960, 8 of the subjects exhibited a greater than 25% decrease in the number of seizures. Seventeen cases showed no change, and one case showed exacerbation. The correct reaction times for Sternberg's paradigm in the group administered TJ-960 were 955 +/- 307 ms at the time of the first examination and 881 +/- 277 ms at the time of the second, and those of the control group were 845 +/- 288 ms for the first examination and 829 +/- 269 ms for the second. As these figures show, the correct reaction time was significantly shortened between the first and second examinations in the TJ-960 group. No change was exhibited in the sample reaction time between the first and second examination in either group. The difference in alpha wave power of the occipital region before and after the TJ-960 administration was significantly greater in the patients who showed improvement in Sternberg's paradigm as compared to the patients who remained unchanged in Sternberg's paradigm. In addition, the results for the theta wave power were opposite to those of alpha waves. As mentioned above, TJ-960 was presumed to have the effect of improving the cognitive function in epileptic patients.