ABSTRACT
BACKGROUND: Individuals with subjective cognitive impairment (SCI) have persistent memory complaints but normal neurocognitive performance. For some, this may represent a pre-mild cognitive impairment (MCI) stage of Alzheimer's disease (AD). Given that attentional deficits and associated brain activation changes are present early in the course of AD, we aimed to determine whether SCI is associated with brain activation changes during attentional processing. METHODS: Eleven SCI subjects and 10 controls completed a divided attention task during functional magnetic resonance imaging. RESULTS: SCI and control groups did not differ in sociodemographic, neurocognitive or behavioural measures. When group activation during the divided attention task was compared, the SCI group demonstrated increased activation in left medial temporal lobe, bilateral thalamus, posterior cingulate and caudate. CONCLUSION: This pattern of increased activation is similar to the pattern of decreased activation reported during divided attention in AD and may indicate compensatory changes. These findings suggest the presence of early functional changes in SCI; longitudinal studies will help to further elucidate the relationship between SCI and AD.
Subject(s)
Alzheimer Disease , Attention/physiology , Brain Mapping/methods , Task Performance and Analysis , Aged , Aged, 80 and over , Alzheimer Disease/pathology , Alzheimer Disease/physiopathology , Alzheimer Disease/psychology , Brain/pathology , Brain/physiopathology , Early Diagnosis , Female , Humans , Intelligence Tests , Magnetic Resonance Imaging , Male , Mental Recall/physiology , Middle Aged , Neuropsychological Tests , Reaction Time/physiology , Severity of Illness Index , Sickness Impact ProfileABSTRACT
People with Subjective Cognitive Impairment (SCI) may be at increased risk of dementia. In this study we examined amyloid load in 5 SCI subjects and 14 controls using PIB PET scanning. One SCI subject had significantly increased PIB retention in the cortical areas of interest. Larger, longitudinal studies are indicated.
Subject(s)
Amyloid/metabolism , Cerebral Cortex/metabolism , Cognition Disorders/diagnosis , Cognition , Dementia/diagnosis , Memory , Positron-Emission Tomography , Aged , Biomarkers/metabolism , Carbon Radioisotopes , Cerebral Cortex/diagnostic imaging , Cognition Disorders/diagnostic imaging , Cognition Disorders/psychology , Dementia/diagnostic imaging , Dementia/psychology , Female , Humans , Image Processing, Computer-Assisted , Male , Middle Aged , Neuropsychological Tests , Risk Factors , United KingdomABSTRACT
The studies cited in this paper demonstrate that the unique environment provided by L. B. films and supported multilayers can produce a variety of molecular effects on photochemical reactivity that can, in turn, result in films, interfaces or surfaces having macroscopic properties which can be modulated by light. Although these investigations have been focused on molecular reactivity in films and how it can be modified (or persist unchanged), the results suggest several possible technological applications which might result from investigations directed more closely to them.
