@article{khan_mondino_russell_case_fefer_woods_olby_gruen_2023, title={A novel task of canine olfaction for use in adult and senior pet dogs}, volume={13}, ISSN={["2045-2322"]}, url={https://europepmc.org/articles/PMC9908929}, DOI={10.1038/s41598-023-29361-x}, abstractNote={While much work has been done in the field of canine olfaction, there has been little exploration of hyposmia or anosmia. This is partly due to difficulties in reducing confounds like training history and environmental distraction. The current study describes a novel olfaction test using spontaneous search behavior in dogs to find a hidden food treat in a three-choice task with both light-phase and dark-phase conditions. The study was performed in 18 adult control dogs, 18 senior/geriatric dogs enrolled in a longitudinal aging study, and a single dog with severe nasal pathology. In the senior/geriatric and control groups, dogs performed with higher accuracy (p < 0.0001) and were less likely to show biased selection strategy (p < 0.01) in the dark-phase than light-phase. While senior/geriatric dogs performed above chance, they had lower accuracy in the dark-phase compared to controls (p = 0.036). Dogs who scored higher on an owner questionnaire of cognitive decline showed a positive correlation with performance in the dark-phase; performance on additional cognitive tests did not correlate with performance in the dark-phase. This task can be used to quantify canine olfaction using clearly defined endpoints and spontaneous behaviors thus making it feasible to compare between and within groups of pet dogs.}, number={1}, journal={SCIENTIFIC REPORTS}, author={Khan, Michael Z. and Mondino, Alejandra and Russell, Katharine and Case, Beth and Fefer, Gilad and Woods, Hope and Olby, Natasha and Gruen, Margaret}, year={2023}, month={Feb} }
 @article{mondino_khan_case_giovagnoli_thomson_lascelles_gruen_olby_2023, title={Activity patterns are associated with fractional lifespan, memory, and gait speed in aged dogs}, volume={13}, ISSN={["2045-2322"]}, url={https://europepmc.org/articles/PMC9929073}, DOI={10.1038/s41598-023-29181-z}, abstractNote={Maintaining an active lifestyle is considered a hallmark of successful aging. Physical activity significantly reduces the risk of cognitive decline and Alzheimer's disease in humans. However, pain and lack of motivation are important barriers to exercise. Dogs are a remarkable model for translational studies in aging and cognition as they are prone to Canine Cognitive Dysfunction syndrome, which has many similarities with Alzheimer's disease. According to owner reports, changes in activity levels are characteristic of this syndrome, with decreased daytime activity, but also excessive pacing, especially at sleep time. We used physical activity monitors to record the activity of 27 senior dogs and evaluated the association between activity level and age, fractional lifespan, cognitive status measured by an owner questionnaire and cognitive tests. We also assessed the relationship between activity and joint/spinal pain, and the off/on leash gait speed ratio (a potential marker of gait speed reserve and motivation). We found that activity patterns in dogs are associated with fractional lifespan and working memory. Additionally, dogs with higher on/off leash gait speed are more active in the afternoon of weekdays. These results encourage future studies evaluating how physical activity can improve or delay cognitive impairment in senior dogs.}, note={PMID: 36788306; PMCID: PMC9929073.}, number={1}, journal={SCIENTIFIC REPORTS}, author={Mondino, Alejandra and Khan, Michael and Case, Beth and Giovagnoli, Sara and Thomson, Andrea and Lascelles, B. Duncan X. and Gruen, Margaret and Olby, Natasha}, year={2023}, month={Feb} }
 @article{khan_mondino_russell_case_fefer_woods_olby_gruen_2023, title={Relationship between engagement with the impossible task, cognitive testing, and cognitive questionnaires in a population of aging dogs}, volume={9}, ISSN={["2297-1769"]}, DOI={10.3389/fvets.2022.1052193}, abstractNote={Introduction The aim of this study was to evaluate the engagement of aging dogs with a cognitively challenging and potentially frustrating task (the impossible task). Based on previous observations, we predicted that dogs showing signs of cognitive impairment in other cognitive tests and owner-completed questionnaires would show reduced engagement with the task. Methods In this task, dogs were shown a piece of food in a clear container that they could not open; time spent interacting with the container and the experimenter was measured. While the impossible task has not been used as a measure of frustration, the parameters of the test design creates a potential frustrate state, making this assessment appropriate. Thirty-two dogs enrolled in a longitudinal aging study participated in the study. Owners were asked to complete two cognitive dysfunction screening questionnaires (Canine Dementia Scale [CADES] and Canine Cognitive Dysfunction Rating Scale [CCDR]) as well a questionnaire assessing general frustration. Dogs participated in multiple measures of cognitive function as well the impossible task. Results Latency to disengage from the impossible task was faster for dogs with higher total (more impaired) CADES (p = 0.02) and total CCDR (p = 0.04) scores. Latency to disengage also correlated with decreased performance in cognitive tests observing social cues (p = 0.01), working memory (p ≤ 0.001), spatial reasoning and reversal learning (p = 0.02), and sustained attention (p = 0.02). Discussion The high correlation with several cognitive measures and the ease of administration of this test makes it a useful tool in evaluating canine cognitive dysfunction syndrome, however it is unclear if increased frustration or other cognitive processes are contributing to the observed changes.}, journal={FRONTIERS IN VETERINARY SCIENCE}, author={Khan, Michael Z. and Mondino, Alejandra and Russell, Katharine and Case, Beth and Fefer, Gilad and Woods, Hope and Olby, Natasha J. and Gruen, Margaret E.}, year={2023}, month={Jan} }
 @article{mondino_catanzariti_mateos_khan_ludwig_kis_gruen_olby_2023, title={Sleep and cognition in aging dogs. A polysomnographic study}, volume={10}, ISSN={["2297-1769"]}, DOI={10.3389/fvets.2023.1151266}, abstractNote={Introduction Sleep is fundamental for cognitive homeostasis, especially in senior populations since clearance of amyloid beta (key in the pathophysiology of Alzheimer's disease) occurs during sleep. Some electroencephalographic characteristics of sleep and wakefulness have been considered a hallmark of dementia. Owners of dogs with canine cognitive dysfunction syndrome (a canine analog to Alzheimer's disease) report that their dogs suffer from difficulty sleeping. The aim of this study was to quantify age-related changes in the sleep-wakefulness cycle macrostructure and electroencephalographic features in senior dogs and to correlate them with their cognitive performance. Methods We performed polysomnographic recordings in 28 senior dogs during a 2 h afternoon nap. Percentage of time spent in wakefulness, drowsiness, NREM, and REM sleep, as well as latency to the three sleep states were calculated. Spectral power, coherence, and Lempel Ziv Complexity of the brain oscillations were estimated. Finally, cognitive performance was evaluated by means of the Canine Dementia Scale Questionnaire and a battery of cognitive tests. Correlations between age, cognitive performance and sleep-wakefulness cycle macrostructure and electroencephalographic features were calculated. Results Dogs with higher dementia scores and with worse performance in a problem-solving task spent less time in NREM and REM sleep. Additionally, quantitative electroencephalographic analyses showed differences in dogs associated with age or cognitive performance, some of them reflecting shallower sleep in more affected dogs. Discussion Polysomnographic recordings in dogs can detect sleep-wakefulness cycle changes associated with dementia. Further studies should evaluate polysomnography's potential clinical use to monitor the progression of canine cognitive dysfunction syndrome.}, journal={FRONTIERS IN VETERINARY SCIENCE}, author={Mondino, Alejandra and Catanzariti, Magaly and Mateos, Diego Martin and Khan, Michael and Ludwig, Claire and Kis, Anna and Gruen, Margaret E. and Olby, Natasha J.}, year={2023}, month={Apr} }
 @article{mondino_khan_case_fefer_panek_gruen_olby_2023, title={Winning the race with aging: age-related changes in gait speed and its association with cognitive performance in dogs}, volume={10}, ISSN={["2297-1769"]}, DOI={10.3389/fvets.2023.1150590}, abstractNote={Introduction In humans, gait speed is a crucial component in geriatric evaluation since decreasing speed can be a harbinger of cognitive decline and dementia. Aging companion dogs can suffer from age-related mobility impairment, cognitive decline and dementia known as canine cognitive dysfunction syndrome. We hypothesized that there would be an association between gait speed and cognition in aging dogs. Methods We measured gait speed on and off leash in 46 adult and 49 senior dogs. Cognitive performance in senior dogs was assessed by means of the Canine Dementia Scale and a battery of cognitive tests. Results We demonstrated that dogs' food-motivated gait speed off leash is correlated with fractional lifespan and cognitive performance in dogs, particularly in the domains of attention and working memory. Discussion Food-motivated gait speed off leash represents a relatively easy variable to measure in clinical settings. Moreover, it proves to be a more effective indicator of age-related deterioration and cognitive decline than gait speed on leash.}, journal={FRONTIERS IN VETERINARY SCIENCE}, author={Mondino, Alejandra and Khan, Michael and Case, Beth and Fefer, Gilad and Panek, Wojciech K. and Gruen, Margaret E. and Olby, Natasha J.}, year={2023}, month={Jun} }
 @article{fefer_khan_panek_case_gruen_olby_2022, title={Relationship between hearing, cognitive function, and quality of life in aging companion dogs}, volume={8}, ISSN={["1939-1676"]}, url={https://doi.org/10.1111/jvim.16510}, DOI={10.1111/jvim.16510}, abstractNote={Abstract Background Elderly people with presbycusis are at higher risk for dementia and depression than the general population. There is no information regarding consequences of presbycusis in dogs. Objective Evaluate the relationship between cognitive function, quality of life, and hearing loss in aging companion dogs. Animals Thirty‐nine elderly companion dogs. Methods Prospective study. Hearing was evaluated using brainstem auditory evoked response (BAER) testing. Dogs were grouped by hearing ability. Owners completed the canine dementia scale (CADES) and canine owner‐reported quality of life (CORQ) questionnaire. Cognitive testing was performed, and cognitive testing outcomes, CADES and CORQ scores and age were compared between hearing groups. Results Nineteen dogs could hear at 50 dB, 12 at 70 dB, and 8 at 90 dB with mean ages (months) of 141 ± 14, 160 ± 16, and 172 ± 15 for each group respectively (P = .0002). Vitality and companionship CORQ scores were significantly lower as hearing deteriorated (6.6‐5.4, 50‐90 dB group, P = .03 and 6.9‐6.2, 50‐90 dB group, P = .02, respectively). Cognitive classification by CADES was abnormal in all 90 dB group dogs and normal in 3/12 70 dB group and 11/19 50 dB group dogs (P = .0004). Performance on inhibitory control, detour and sustained gaze tasks decreased significantly with hearing loss (P = .001, P = .008, P = .002, respectively). In multivariate analysis, higher CADES score was associated with worse hearing (P = .01). Conclusions and Clinical Importance Presbycusis negatively alters owner‐pet interactions and is associated with poor executive performance and owner‐assessed dementia severity.}, journal={JOURNAL OF VETERINARY INTERNAL MEDICINE}, author={Fefer, Gilad and Khan, Michael Z. and Panek, Wojciech K. and Case, Beth and Gruen, Margaret E. and Olby, Natasha J.}, year={2022}, month={Aug} }
 @article{fefer_panek_khan_singer_westermeyer_mowat_murdoch_case_olby_gruen_2022, title={Use of Cognitive Testing, Questionnaires, and Plasma Biomarkers to Quantify Cognitive Impairment in an Aging Pet Dog Population}, volume={87}, ISSN={["1875-8908"]}, DOI={10.3233/JAD-215562}, abstractNote={BACKGROUND
Aging dogs suffer from canine cognitive dysfunction syndrome (CCDS), a condition in which cognitive decline is associated with amyloid pathology and cortical atrophy. Presumptive diagnosis is made through physical examination, exclusion of systemic/metabolic conditions, and completion of screening questionnaires by owners.


OBJECTIVE
This study aimed to determine whether cognitive function could be quantified in aging pet dogs, and to correlate cognitive testing with validated questionnaires and plasma neurofilament light chain (pNfL) concentration in aging dogs.


METHODS
Thirty-nine dogs from fifteen breeds were recruited (9.3 to 15.3 years). Owners completed the Canine Dementia Scale (CADES) and Canine Cognitive Dysfunction Rating scale (CCDR). Executive control and social cues were tested, and pNfL was measured with single molecule array assay. Comparisons were made between cognitive testing scores, CADES, CCDR scores, and pNfL.


RESULTS
CADES scoring classified five dogs as severe CCDS, six as moderate, ten as mild, and eighteen as normal. CCDR identified seven dogs at risk of CCDS and thirty-two as normal. Cognitive testing was possible in the majority of dogs, although severely affected dogs were unable to learn tasks. CADES score correlated with sustained attention duration (r = -0.47, p = 0.002), inhibitory control (r = -0.51, p = 0.002), detour (r = -0.43, p = 0.001), and pNfL (r = 0.41, p = 0.025). Concentration of pNfL correlated with inhibitory control (r = -0.7, p≤0.001). The CCDR scale correlated with performance on inhibitory control (r = -0.46, p = 0.005).


CONCLUSION
Our findings suggest that a multi-dimensional approach using a combination of questionnaires, specific cognitive tests, and pNfL concentration can be used to quantify cognitive decline in aging pet dogs.}, number={3}, journal={JOURNAL OF ALZHEIMERS DISEASE}, author={Fefer, Gilad and Panek, Wojciech K. and Khan, Michael Z. and Singer, Matthew and Westermeyer, Hans D. and Mowat, Freya M. and Murdoch, David M. and Case, Beth and Olby, Natasha J. and Gruen, Margaret E.}, year={2022}, pages={1367–1378} }