BACKGROUND/AIMS:The diagnostic accuracy of the German version of the revised Addenbrooke's Cognitive Examination (ACE-R) in identifying mild cognitive impairment (MCI), mild dementia in Alzheimer's disease (AD) and mild dementia in frontotemporal lobar degeneration (FTLD) in comparison with the conventional Mini Mental State Examination (MMSE) was assessed.METHODS:The study encompasses 76 cognitively healthy elderly individuals, 75 patients with MCI, 56 with AD and 22 with FTLD. ACE-R and MMSE were validated against an expert diagnosis based on a comprehensive diagnostic procedure. Statistical analysis was performed using the receiver operating characteristic method and regression analyses.RESULTS:The optimal cut-off score for the ACE-R for detecting MCI, AD, and FTLD was 86/87, 82/83 and 83/84, respectively. ACE-R was superior to MMSE only in the detection of patients with FTLD [area under the curve (AUC): 0.97 vs. 0.92], whilst the accuracy of the two instruments did not differ in identifying MCI and AD. The ratio of the scores of the memory ACE-R subtest to verbal fluency subtest contributed significantly to the discrimination between AD and FTLD (optimal cut-off score: 2.30/2.31, AUC: 0.77), whereas the MMSE and ACE-R total scores did not.CONCLUSION:The German ACE-R is superior to the most commonly employed MMSE in detecting mild dementia in FTLD and in the differential diagnosis between AD and FTLD. Thus it might serve as a valuable instrument as part of a comprehensive diagnostic workup in specialist centres/clinics contributing to the diagnosis and differential diagnosis of the cause of dementia.

Hemiplegic migraine (HM) is a rare and severe subtype of migraine with aura, characterized by some degree of hemiparesis and other aura symptoms. Mutations in three genes (CACNA1A, ATP1A2 and SCN1A) have been detected in familial and, more rarely, in sporadic cases. The disease can be complicated by permanent neurological deficits, the most frequent one being a cerebellar syndrome; in addition, mental retardation has been recognized as part of the phenotypic spectrum. Here, we report a Caucasian male with a novel CACNA1A mutation and an unusual clinical phenotype: the patient, who had had a history of only two HM attacks, sought medical advice at age 49 primarily because of increasing cognitive decline accompanied by cerebellar dysfunction. While common neurodegenerative causes were excluded, neuropsychological evaluation revealed a distinct profile of deficits of a subcortico-prefrontal type as previously reported in patients with cerebellar dysfunction. This suggests a possible causal link between cerebellar and cognitive disturbances in this patient; in addition to these pathophysiological aspects, we review of the role of the cerebellum in cognition.

A 60-year-old male caucasian patient underwent shoulder surgery under total intravenous anaesthesia. Medical history included arterial hypertension and coronary artery disease. Following the otherwise uncomplicated surgery, the patient presented with a postoperative confusional state and was referred to our neurological department. Neurological examination revealed marked anterograde amnesia with a milder retrograde defect covering approximately 3 months. Furthermore, there was an obvious visual disturbance: the patient was unable to read and exhibited prosopagnosia, not being able even to recognize familiar faces (e.g. from presented photographs of famous people). Memory span was reduced to a few minutes and the patient would not recognize people shortly after an encounter, not only visually by faces due to prosopagnosia, but also acoustically by voices. The latter was true for unknown people, while he was able to acoustically identify familiar people (e.g. relatives), thus most likely reflecting anterograde amnesia. The neurological examination was otherwise unremarkable, especially there was no aphasia, and the patient was able to calculate and to write. Formal memory testing (e.g. Rivermead Behavioural Memory Test; California verbal learning test) confirmed the marked anterograde amnesia. Due to the clinically obvious visual disturbance, ophthalmologic examination including perimetry was performed and revealed stato-dynamic visual dissociation [1], with a right paracentral scotoma upon static perimetry and – in contrast – retained perception of dynamic stimuli. In accordance with this finding, detailed neuropsychological testing revealed alexia and marked visual agnosia for figures or objects presented to the patient statically, which he was unable to identify, i.e. name or describe their function. Furthermore, for example, he would not be able to identify parallel lines or to read a clock. In contrast, there was correct mentalspatial representation of figures presented dynamically: he was able to read a clock when the clock was drawn by another person. Also, he was able to correctly copy figures which he watched as they were being drawn (e.g. letters, numbers, geometric figures such as a house, the sun, etc.) as well as objects moved into his visual field (e.g. a pen, a bottle, etc.). However, he exhibited difficulties in naming these objects or describing their function. The same – however to a lesser extent than for visually presented objects – was true for objects presented tactilely. In contrast, he was able to recognize objects by name. Interestingly, the patient was overall fully aware of his deficits and stated himself that he was suffering from the Groundhog-day-syndrome , i.e. the feeling of being in a repetitive time-loop and experiencing the same situation over and over again (as adopted from the socalled movie). Magnetic resonance imaging (MRI) of the brain showed an unusual pattern of pathologic signal alterations on diffusionweighted imaging (DWI): there was pathologic diffusion restriction affecting the hippocampus and inferior occipital cortex bilaterally, in accordance with the clinical picture (Fig. 1a). Also, both cerebellar hemispheres were affected. The symmetric lesion distribution with bilateral hippocampal involvement possibly reflects hypoxic changes [2] and was rather atypical for cerebral ischaemia. However, the latter can also not be excluded. Cardiovascular diagnostic work-up (including transesophageal echocardiogram, Doppler-/duplexsonography of extraand intracranial arterial vessels, 24 h HolterECG, cranial MR-Angiography, CT of the aortic arch) was unremarkable except for some atherosclerotic vascular changes. Furthermore, EEG and extensive blood tests were normal. The clinical state lasted throughout the whole 2 week period of hospitalization, with subtle improvement over time. Upon

Background: Herpes simplex virus infection of the central nervous system can manifest as potentially life- threatening necrotizing encephalitis that primarily affects the medial and inferior temporal lobe. Clinical features of acute Herpes simplex encephalitis are fever, headache, Wernicke's aphasia, epileptic seizures, confusion and reduced levels of consciousness. The affection of the temporal lobe and the limbic system may cause a significant and sometimes persisting memory impairment. However, there is evidence for a post-developmental neurogenesis in the adult human brain, especially in the temporal lobe (hippocampal dentate gyrus).

Prosopagnosie, die Unfähigkeit Personen alleine am Gesicht zu erkennen, kann auch als kongenitale, oft autosomal-dominant erbliche Eigenschaft auftreten. Beim Kallmann-Syndrom (KS) handelt es sich um einen hypogonadotropen Hypogonadismus mit Anosmie, der durch eine Störung des Wachstums der Axone von der olfaktorischen Plakode in das ZNS bedingt ist. Wir berichten über einen Fall von KS, bei dem wir Hinweise auf kongenitale Prosopagnosie fanden.