Visuospatial function in the beagle dog: An early marker of cognitive decline in a model of human aging and dementia

• Published in: Neurobiology of learning and memory Vol. 86; no. 2; pp. 197 - 204
• Main Authors: Studzinski, Christa M., Christie, Lori-Ann, Araujo, Joseph A., Burnham, W. McIntyre, Head, Elizabeth, Cotman, Carl W., Milgram, Norton W.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01.09.2006; Elsevier; Elsevier BV
• Subjects: Aging; Aging - physiology; Alzheimer's disease; Animals; Behavioral psychophysiology; Biological and medical sciences; Biomarkers; Cognition Disorders - diagnosis; Cognition Disorders - etiology; Cognition Disorders - physiopathology; Degenerative and inherited degenerative diseases of the nervous system. Leukodystrophies. Prion diseases; Delayed non-matching to position; Dementia; Dementia - complications; Dementia - diagnosis; Dementia - physiopathology; Discrimination Learning - physiology; Disease Models, Animal; Dog; Dogs; Female; Follow-Up Studies; Fundamental and applied biological sciences. Psychology; Learning; Male; Medical sciences; Memory; Neurology; Photic Stimulation; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Space Perception - physiology; Spatial; Spatial Behavior - physiology; Visual Perception - physiology; Visuospatial function; Learning; Delayed non-matching to position; Visuospatial function; Spatial; Memory; Aging; Dog; Dementia; Senescence; Cognitive disorder; Space perception; Acquisition process; Degenerative disease; Human; Fissipedia; Carnivora; Nervous system diseases; Cerebral disorder; Senile dementia; Vertebrata; Mammalia; Animal; Vision; Central nervous system disease; Early; Models
• ISSN: 1074-7427; 1095-9564
• DOI: 10.1016/j.nlm.2006.02.005

Visuospatial learning and memory impairments are an early marker for age-related cognitive decline and Alzheimer’s disease. Similar to humans, aged dogs show visuospatial learning and memory deficits ( Adams et al., 2000b). One hundred and nine beagle dogs ranging between 0.25 and 11.99 years were tested on a visuospatial delayed non-matching to position (DNMP) task to better characterize the progression of visuospatial deficits in the dog. Age predicted 48.2% of the variability in learning the DNMP, with dogs ranging from 1 to 11.99 years generally making more errors with increasing age. By contrast, puppies (<1 year) likely were showing developmental deficits, possibly due to an immature prefrontal cortex. Mild visuospatial deficits were detected by 6 years, which precedes the typical onset of amyloid-β (Aβ) accumulation in the dog brain by two years, and can serve as an early marker for cognitive decline in the dog. These findings suggest that (1) age-related changes in visuospatial function in the dog models that seen in humans, further validating the dog as a model for human aging and dementia; and (2) other mechanisms, such as oxidative stress, soluble Aβ oligomers or cholinergic deficits, are likely contributing to the early impairment.