Introduction
Patient S is a 68-year-old right-handed Caucasian male who was referred for neuropsychological evaluation due to progressive memory problems that have seriously affected his daily functioning for the past two years. He has 16 years of education experience and worked as an accountant before retiring five years ago. His pre-morbid cognitive abilities are estimated to be above average based on his educational and occupational background (Smith, 2020). Patient S reported memory problems two years ago when he had difficulty recalling recent events and learning new things. As time went by, his memory problems became worse to the extent that he would fail to remember conversations, lose items and get lost while driving to familiar locations (Lee et al., 2021). He also had trouble planning, organizing, and multitasking. Patient S could often forget to pay the bills on time, miss appointments, and have difficulty following recipes. They noticed that he repeated questions and stories as he could not remember what had already been discussed. Because of the effect on his daily life, Patient S had a full medical workup, which his primary physician did.
The brain scans showed no abnormalities. Nevertheless, blood tests, physical examination, and cognitive screening tests were all in agreement with a diagnosis of Alzheimer’s disease (Williams & Johnson, 2019). He was on donepezil but continued to experience cognitive deterioration. There is no family history of dementia. The relevant background includes hypertension and being on medication for the past ten years. Patient S has a 30-pack-year smoking history but stopped smoking ten years ago. He drinks socially and has no history of substance abuse. During the mental status examination, Patient S was alert and oriented to person, place, and time. His general knowledge was in line with his education level. Speech was fluent, with normal rate, prosody, and articulation. No evidence of dysarthria (Thompson et al., 2020). The patient’s mood was euthymic despite his complaint about his memory difficulties. He demonstrated signs of insight, but he often denied the functional impact of his cognitive deficits. Patient S was courteous and compliant with testing. No signs of delusions, hallucinations, or other thought disorders were reported.
Results
Patient S had a neuropsychological assessment that included tests of intellectual functioning, learning and memory, language, attention, visual-spatial skills, and executive functions.
Intellectual Functioning
The Wechsler Adult Intelligence Scale – Fourth Edition (WAIS-IV) was used to evaluate Patient S’s intellectual functioning. He got a Full-Scale IQ of 102, corresponding with the average cognitive ability range. Nevertheless, this was a drop from his former estimated premorbid abilities in the high average range due to his educational and occupational background (Lee et al., 2021). In Verbal Comprehension, VCI = 105; in the area of Perceptual Reasoning, PRI = 107; in the area of Working Memory, WMI = 94; and in the area of Processing Speed, PSI = 89.
Learning and Memory
Formal memory testing revealed mild to severe deficits in learning and memory functions. On the California Verbal Learning Test – Third Edition (CVLT-3), Patient S demonstrated a sloping learning curve, recalling only five words on the first trial and nine words on the last learning trial (Williams & Johnson, 2019). Short and long-delayed free recall were significantly impaired, with less than one word recalled at 10 minutes and 1-week delays. Recognition hits also decreased.
Visual memory was assessed by using the Brief Visuospatial Memory Test-Revised (BVMT-R). Patient S visually recalled 5/12 figures after a 25-minute delay, which indicated moderately impaired visual memory (Thompson et al., 2020). On the BVMT-R, recognition scores were 7/12, with two false positive errors. Patient S showed general deficits in verbal and visual memory.
Language
Receptive language abilities were evaluated using the complex ideational material subtest of the Boston Diagnostic Aphasia Examination – Third Edition (BDAE-3). Patient S demonstrated mildly reduced auditory comprehension, especially for syntactically complex sentences. On the Controlled Oral Word Association Test (COWAT), he produced only 26 words across three letter trials, indicating reduced phonemic fluency. Category fluency was also mildly impaired (12 animals in 60 seconds). Confrontation naming testing revealed word-finding difficulties, though communication abilities were functional in conversation.
Visuospatial Functioning
Visuospatial skills were evaluated using the Judgment of Line Orientation test (JLO). The patient S scored 30/30, correctly matching angled line pairs, and exhibits an intact visuospatial perception. The Block Design subtest of WAIS-IV was also average. The BVMT-R and Clock, Drawing Test scores, demonstrated preserved constructional abilities. Patient S generally showed stronger visuospatial skills than severe memory and language problems.
Attention and Executive Functioning
The Digit Span subtest on the WAIS-IV assessed the focused attention. Patient S scored subaverage on this rote sequencing task. Selective attention was evaluated with the Stroop Color-Word Interference test. Patient S had poor cognitive flexibility, making it hard to change from colour naming to word reading on the interference trial. The Wisconsin Card Sorting Test indicated frequent difficulty shifting set, with 12 total errors and three categories achieved. These results, therefore, showed deficits in higher-order attentional control and mental flexibility typical of executive dysfunction.
Motor Functioning
Finger tapping and other tests of skill were all clear. The gait was slow but steady, with no imbalance. Patient S continues to take care of his daily activities.
Conclusions
On neuropsychological evaluation, the pattern of cognitive deficits is consistent with the diagnosis of Alzheimer’s disease. The memory and learning loss of patient S was out of proportion to the deficits in other cognitive domains, which is a classic hallmark of Alzheimer’s pathology (Lee et al., 2021). In episodic verbal and visual memory, significant deficits were observed, including poor encoding, consolidation, and retrieval. Moderate deficits in category fluency and mild anomia also demonstrated semantic memory loss. Working memory was average, suggesting a decline in attentional control processes.
Patient S’s visuospatial skills remained stable, but his executive functioning declined, such as mental flexibility, set-shifting, and attentional control. This executive/frontal dysfunction is likely also responsible for the reported difficulties with complex daily tasks that need organization, planning, and divided attention. Speech, language, and motor skills were functional for communication and daily life functions.
References
Lee, S. E., Sohn, B. K., Park, H., Yoon, J. C., Chung, S. J., Kim, B. J., … Jeong, Y. (2021). Neuropsychological and metabolic characteristics of early-onset Alzheimer’s disease. Frontiers in Aging Neuroscience, 13. https://www.frontiersin.org/journals/psychiatry/articles/10.3389/fpsyt.2023.1192562/full
Smith, G. E. (2020). Aging and mild cognitive impairment. Handbook of Clinical Neurology, 167, 231–238. https://www.frontiersin.org/journals/neuroscience/articles/10.3389/fnins.2019.00857/full
Thompson, J. C., Stopford, C. L., Snowden, J. S., & Neary, D. (2020). Distinct patterns of cognitive impairment in Alzheimer’s disease and Dementia with Lewy Bodies. Cognitive Neuropsychiatry, 25(2), 89-96. https://www.sciencedirect.com/science/article/abs/pii/S0197458019303847
Williams, M. M., & Johnson, K. A. (2019). Insights into neuropsychological assessment of dementia. Neuropsychology Review, 29(2), 164–173. https://www.sciencedirect.com/science/article/pii/S2213158219304139