Impaired integration of object feature knowledge in amnestic mild cognitive impairment
| Autor: | Elena K. Festa, William C. Heindel, Geoffrey Tremont, Laura E. Korthauer, Leslie Y Lai, Brian R. Ott |
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| Rok vydání: | 2020 |
| Předmět: |
Male
media_common.quotation_subject Amnesia Color Neuropathology Neuropsychological Tests Semantics Alzheimer Disease Perception Perirhinal cortex medicine Semantic memory Humans Cognitive Dysfunction media_common Aged Aged 80 and over Cerebral Cortex Middle Aged Object (computer science) Feature (linguistics) Neuropsychology and Physiological Psychology medicine.anatomical_structure Positron-Emission Tomography Mental Recall Female medicine.symptom Psychology Photic Stimulation Cognitive psychology |
| Zdroj: | Neuropsychology. 34(6) |
| ISSN: | 1931-1559 |
| Popis: | Objective Accessing semantic representations of real-world objects requires integration of multimodal perceptual features that are represented across relevant neocortical areas. Early Alzheimer's disease (AD) neuropathology, including neurofibrillary tangles in the perirhinal cortex as well as disrupted cortico-cortical connectivity, would be expected to disrupt the integration of object features. This integration deficit may underlie AD patients' semantic memory deficits and would be predicted to be more prominent for living objects, which tend to be more defined by sensory features compared with nonliving objects. Method Two experiments were conducted to assess feature integration in cognitively healthy older adults and patients with amnestic mild cognitive impairment (MCI). In both experiments, pictures of real-world objects were presented in congruent or incongruent colors. Participants were instructed to make a speeded color congruency judgment (Experiment 1) or name the presented surface color (Experiment 2). Results Across experiments, MCI patients showed a selective integration deficit for living, but not nonliving, objects across both experimental paradigms that was consistent with a deterioration in semantic structural representations rather than a deficit in controlled semantic retrieval. Planned secondary analyses with a subset of patients (Experiment 1) for whom PET imaging was available indicated that the degree of impairment was associated with the magnitude of cortical amyloid burden. Conclusions These findings suggest that early AD pathology leads to impaired integration of distributed semantic object representations. The development of integration tasks as sensitive markers of early AD pathology may lead to more effective diagnostic tools for early detection and intervention. (PsycInfo Database Record (c) 2020 APA, all rights reserved). |
| Databáze: | OpenAIRE |
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