Alzheimer disease 1 Alzheimer’s disease 1 Article 1 Blood–brain barrier 1 Cognition 1 Color Word Stroop Test 1 Digit Span Test Go No Go task 1 Regional cerebral metabolic rate of glucose 1 Seoul Verbal Learning Test 1 Transcranial focused ultrasound 1 aged 1 aquasonic 1 blood brain barrier 1 clinical article 1 cohort analysis 1 contrast enhancement 1 controlled oral word association test 1 cryogel 1 dynamic contrast-enhanced magnetic resonance imaging 1 electrocardiography 1 female 1 fluorodeoxyglucose f 18 1 focused ultrasound therapy 1 follow up 1 hippocampus 1 human 1 hydrogel 1 image analysis 1 male 1