[Establishment of a short-form screening test for cognitive decline as part of a newly developed comprehensive geriatric assessment initiative named 'Dr. Superman']. | LitMetric
Aim: The assessment of cognitive function is important in comprehensive geriatric assessment (CGA), and several standardized screening tests for dementia such as the Mini-Mental State Examination (MMSE) are available. However, it takes 5 to 20 minutes to perform the MMSE. We have developed a CGA initiative named 'Dr. Superman' which is designed to accomplish CGA within 10 minutes. In this study, we evaluated a short-form screening test for cognitive decline preceding the MMSE.
Methods: The MMSE and a question on episodic memory, ("What kind of food did you have last night?") were administered to 90 elderly outpatients with various diseases. They were divided into 2 groups according to their MMSE scores: a normal group (MMSE score≥24) and an abnormal group (MMSE score≤23). Within these groups, each domain (D) (D1: time orientation, D2: place orientation, D3: immediate memory, D4: calculation, D5: recall, D6: language, and D7: spatial cognition) and episodic memory was separately scored and the sensitivity, specificity, and positive predicative value of each were calculated. Based on these data, the best combination of the domains was evaluated for practical use as an assessment tool.
Results: The MMSE scores ranged from 10 to 30, and 42 cases were classified into the normal group. High sensitivity, specificity, or positive predicative value was observed in D1, D2, D4, D5 and episodic memory categories. On the basis of the characteristics of each item in these domains in order to make a short-form assessment, a combination of "What is this year" in D1, "Serial 7's twice" in D4, and a question on episodic memory was found to be superior to other combinations (sensitivity: 93.8%; specificity: 71.4%; positive predicative value: 78.9%). Using this combination for 50 outpatients with 2 raters, it took 32 to 55 seconds to accomplish the assessment with good inter-rater reliability (κ=0.861).
Conclusions: The combination of "What is this year?", "Serial 7's twice", and "What kind of food did you have last night?" was the best and most valuable short-form screening test for cognitive decline.
In keeping with the historical focus of this special issue of Hippocampus, this paper reviews the history of my development of the SPEAR model. The SPEAR model proposes that separate phases of encoding and retrieval (SPEAR) allow effective storage of multiple overlapping associative memories in the hippocampal formation and other cortical structures. The separate phases for encoding and retrieval are proposed to occur within different phases of theta rhythm with a cycle time on the order of 125 ms.
For most of my career, I focused on understanding how and where spatial context, the place where things happen, is represented in the brain. My interest in this began in the early 1990's, during my postdoctoral training with David Amaral, when we defined the rodent homolog of the primate parahippocampal cortex, a region implicated in processing spatial and contextual information. We parceled out the caudal portion of the rat perirhinal cortex (PER) and called it the postrhinal cortex (POR).
Age-related atrophy of the human hippocampus and the enthorinal cortex starts accelerating at around age 60. Due to the contributions of these regions to many cognitive functions seamlessly used in everyday life, this can heavily impact the lives of elderly people. The hippocampus is not a unitary structure, and mechanisms of its age-related decline appear to differentially affect its subfields.
As requested by the editors of this special issue of Hippocampus on Scientific Histories of Hippocampal Research, this review provides a detailed personal perspective and historical background on the research involved in a number of findings. The review includes description of the development of the water maze and its use in providing evidence to support the role of the hippocampus in spatial memory function. The review also describes how the water maze was then used in further work to support the proposal that NMDA-dependent synaptic modification in the hippocampus mediates the encoding of new spatial memories.
Human aging affects the ability to remember new experiences, in part, because of altered neural function during memory formation. One potential contributor to age-related memory decline is diminished neural selectivity -- i.e.
