Persistent anterograde amnesia following limbic encephalitis associated with antibodies to the voltage-gated potassium channel complex.

OBJECTIVE: Limbic encephalitis (LE) associated with antibodies to the voltage-gated potassium channel complex (VGKC) is a potentially reversible cause of cognitive impairment. Despite the prominence of cognitive dysfunction in this syndrome, little is known about patients' neuropsychological profile at presentation or their long-term cognitive outcome. METHODS: We used a comprehensive neuropsychological test battery to evaluate cognitive function longitudinally in 19 patients with VGKC-LE. RESULTS: Before immunotherapy, the group had significant impairment of memory, processing speed and executive function, whereas language and perceptual organisation were intact. At follow-up, cognitive impairment was restricted to the memory domain, with processing speed and executive function having returned to the normal range. Residual memory function was predicted by the antibody titre at presentation. CONCLUSIONS: The results show that, despite broad cognitive dysfunction in the acute phase, patients with VGKC-LE often make a substantial recovery with immunotherapy but may be left with permanent anterograde amnesia.

Prevalence and clinical characteristics of unremembered nocturnal eating in diabetic subjects: Kurume sleep trouble in obesity and metabolic disorders (KUSTOMED) study.

Nighttime food intake is associated with weight gain and higher HbA1c levels. We experienced night eaters who have no memory of their nocturnal eating in the morning. In this study, the curious night eating behavior was designated as "unremembered nocturnal eating syndrome (UNES)". We screened 1,169 patients with diabetes for sleep quality and abnormal eating behavior at night using the Pittsburgh Sleep Quality Index questionnaire with an additional question regarding UNES. When abnormal nocturnal eating behavior was noted, detailed clinical information was extracted from interviews with the patients. We identified 9 patients who experienced UNES. They had a higher BMI compared with subjects who reported no such episodes. Among them, 6 patients who consumed food at night without memory 2-5 times per month or more had significantly higher HbA1c levels. Continuous glucose monitoring in a patient with type 1 diabetes revealed an abrupt elevation of glucose levels from midnight when some foods were consumed. Eight of the 9 patients were taking benzodiazepine and/or non-benzodiazepine hypnotic agents when they experienced the episodes. The prevalence of UNES was 0.8% in all subjects and 4% in those taking hypnotic drugs. The ratio of hypnotic drug use in subjects with UNES was significantly higher than for individuals without UNES (89% vs. 17%, p<0.0001). Although UNES seems to be etiologically heterogeneous, hypnotics-induced parasomnia and/or anterograde amnesia may be associated with the behavior. UNES is not rare in diabetic patients on hypnotic medicine and may be a hidden cause of unexpected morning hyperglycemia.

Compensating for anterograde amnesia: a new training method that capitalizes on emerging smartphone technologies.

Following a neuropathological event, individuals left with moderate-to-severe memory impairment are unable to reliably form new memories. The most common challenges involve the capacity to perform a task in the future and to consciously recall a recent event. Disruption of these memory processes leaves the individual trapped in the present, unable to stay on track, and alienated from ongoing events. Memory research has demonstrated that implicit memory is often preserved despite severe explicit memory impairment and that preserved memory systems can provide avenues for acquiring new skills and knowledge. A within-subject single-case A1-B1-A2-B2 experimental design was used to introduce an established theory-driven training program of technology use for individuals with moderate-to-severe memory impairment. We describe its application to enabling RR, an individual with memory impairment postcolloid cyst removal, to independently support her memory using a commercial smartphone. RR showed successful outcome on both objective and qualitative measures of memory functioning. Moreover, she demonstrated consistent and creative generalization of acquired smartphone skills across a broad range of real-life memory-demanding circumstances. Our findings suggest that individuals with moderate-to-severe memory impairment are able to capitalize on emerging commercial technology to support their memory.