Dr Katya Numbers

Bachelor of Science, Psychology; Masters of Science, Experimental Psychology; PhD, Cognitive Science

Medicine & Health
Centre for Healthy Brain Ageing

Katya is a Postdoctoral Research Fellow at the Centre for Healthy Brain Ageing (CHeBA) within the Discipline of Psychiatry and Mental Health. Katya is also the former Coordinator of CHeBA's Sydney Memory and Ageing Study. The Memory and Ageing Study (MAS), is one of Australia’s largest and longest running studies of ageing and cognitive health. MAS began in 2005 with the aims of investigating  rates and predictors of healthy cognitive ageing, mild cognitive impairment (MCI) and dementia in older Australians. Over the last 14 years, MAS has collected biomarker, genetic/epigenomic, neuroimaging, cognitive, proteomics, lipidomics, health, and lifestyle data to determine what factors are associated with cognitively normal ageing and progression to MCI or dementia. To date, MAS has contributed data to over 190 papers published in high impact journals and scores of successful Honours, Masters, and PhD projects

Katya's own research focuses on modifiable lifestyle factors associated with increased dementia risk, the subjective experience of cognitive decline and functional ability, the unique impact of COVID-19 and isolation on older adults, and strategies for combatting negative stereotypes of ageing in younger and older adults. Through her research, Katya aims to improve the health and mental health of older adults via numerous pathways. She uses a range of methods, including epidemiological investigation of large datasets, experimental trials, and creation of new computerised and app-based tools to capture physical and mental health in older adults. Though an early career researcher, Katya has published 22 papers in high impact journals, presented her research at 24 national and international conferences, is an Editor and Reviewer for 21 journals, is a named investigator on grants totalling over $4.6M.  

Click here to read Dr Katya Numbers' ‘Meet Our Researcher’ interview

  • Journal articles | 2022
    Kumar SS; Merkin AG; Numbers K; Sachdev PS; Brodaty H; Kochan NA; Trollor JN; Mahon S; Medvedev O, 2022, 'A Novel Approach to Investigate Depression Symptoms in the Aging Population Using Generalizability Theory', Psychological Assessment, http://dx.doi.org/10.1037/pas0001129
    Journal articles | 2022
    Truong QC; Choo C; Numbers K; Merkin AG; Brodaty H; Kochan NA; Sachdev PS; Feigin VL; Medvedev ON, 2022, 'Clinical investigation of dynamic and enduring aspects of global cognition in aged population', European Journal of Clinical Investigation, vol. 52, pp. e13681, http://dx.doi.org/10.1111/eci.13681
    Journal articles | 2021
    Chander RJ; Mather KA; Cleary R; Grainger SA; Thalamuthu A; Numbers K; Kochan NA; Armstrong NJ; Brodaty H; Henry JD; Sachdev P, 2021, 'The influence of rs53576 polymorphism in the oxytocin receptor (OXTR) gene on empathy in healthy adults by subtype and ethnicity: a systematic review and meta-analysis', Reviews in the Neurosciences, http://dx.doi.org/10.1515/revneuro-2021-0038
    Journal articles | 2021
    Jang S; Numbers K; Lam BCP; Sachdev PS; Brodaty H; Reppermund S, 2021, 'Performance-Based vs Informant-Reported Instrumental Activities of Daily Living in Predicting Dementia', Journal of the American Medical Directors Association, http://dx.doi.org/10.1016/j.jamda.2021.09.020
    Journal articles | 2021
    Lennon MJ; Lam BCP; Crawford J; Brodaty H; Kochan NA; Trollor JN; Numbers K; Draper B; Thalamuthu A; Sachdev PS, 2021, 'Does Antihypertensive Use Moderate the Effect of Blood Pressure on Cognitive Decline in Older People?', Journals of Gerontology - Series A Biological Sciences and Medical Sciences, vol. 76, pp. 859 - 866, http://dx.doi.org/10.1093/gerona/glaa232
    Journal articles | 2021
    Numbers K; Brodaty H, 2021, 'The effects of the COVID-19 pandemic on people with dementia', Nature Reviews Neurology, vol. 17, pp. 69 - 70, http://dx.doi.org/10.1038/s41582-020-00450-z
    Journal articles | 2021
    Numbers K; Lam BCP; Crawford JD; Kochan NA; Sachdev PS; Brodaty H, 2021, 'Increased reporting of subjective cognitive complaints over time predicts cognitive decline and incident dementia', International Journal of Geriatric Psychiatry, vol. 36, pp. 1739 - 1747, http://dx.doi.org/10.1002/gps.5594
    Journal articles | 2021
    Page ZA; Croot K; Sachdev PS; Crawford JD; Lam BCP; Brodaty H; Miller Amberber A; Numbers K; Kochan NA, 2021, 'Comparison of Computerised and Pencil-and-Paper Neuropsychological Assessments in Older Culturally and Linguistically Diverse Australians', Journal of the International Neuropsychological Society, http://dx.doi.org/10.1017/S1355617721001314
    Journal articles | 2021
    Stevens A; Numbers K; Samtani S, 2021, 'Are lonely older adults more vulnerable to mental health issues during pandemics?', International Psychogeriatrics, vol. 33, pp. 449 - 451, http://dx.doi.org/10.1017/S104161022100034X
    Journal articles | 2021
    Truong QC; Choo C; Numbers K; Merkin AG; Brodaty H; Kochan NA; Sachdev PS; Feigin VL; Medvedev ON, 2021, 'Applying generalizability theory to examine assessments of subjective cognitive complaints: Whose reports should we rely on - Participant versus informant?', International Psychogeriatrics, pp. 1 - 11, http://dx.doi.org/10.1017/S1041610221000363
    Journal articles | 2021
    Truong QC; Choo C; Numbers K; Merkin AG; Sachdev PS; Feigin VL; Brodaty H; Kochan NA; Medvedev ON, 2021, 'Enhancing precision of the 16-item Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE-16) using Rasch methodology', International Psychogeriatrics, pp. 1 - 11, http://dx.doi.org/10.1017/S1041610221002568
    Journal articles | 2020
    Chander RJ; Grainger SA; Crawford JD; Mather KA; Numbers K; Cleary R; Kochan NA; Brodaty H; Henry JD; Sachdev PS, 2020, 'Development of a short-form version of the Reading the Mind in the Eyes Test for assessing theory of mind in older adults', International Journal of Geriatric Psychiatry, vol. 35, pp. 1322 - 1330, http://dx.doi.org/10.1002/gps.5369
    Journal articles | 2020
    Chander RJ; Numbers KT; Grainger SA; Cleary R; Das D; Mather KA; Kochan NA; Brodaty H; Henry JD; Sachdev PS, 2020, 'Social cognitive abilities in older adults with mild cognitive impairment and dementia', Alzheimer's & Dementia, vol. 16, http://dx.doi.org/10.1002/alz.044231
    Journal articles | 2020
    Lam BCP; Crawford JD; Lipnicki DM; Numbers KT; Kochan NA; Draper B; Trollor JN; Brodaty H; Sachdev PS, 2020, 'The latent construct of dementia phenotype: Validation and longitudinal examination in the Sydney Memory and Ageing Study', Alzheimer's & Dementia, vol. 16, http://dx.doi.org/10.1002/alz.040876
    Journal articles | 2020
    Numbers K; Crawford JD; Kochan NA; Draper B; Sachdev PS; Brodaty H, 2020, 'Participant and informant memory-specific cognitive complaints predict future decline and incident dementia: Findings from the Sydney Memory and Ageing Study', PLOS ONE, vol. 15, pp. e0232961 - e0232961, http://dx.doi.org/10.1371/journal.pone.0232961
    Journal articles | 2020
    Numbers KT; Lam BCP; Crawford JD; Kochan NA; Sachdev PS; Brodaty H, 2020, 'Patterns of change in subjective cognitive complaints are associated with cognitive decline and dementia risk: Findings from the Sydney Memory and Ageing Study', Alzheimer's & Dementia, vol. 16, http://dx.doi.org/10.1002/alz.040685
    Journal articles | 2019
    Bentvelzen AC; Crawford JD; Theobald A; Maston K; Slavin MJ; Reppermund S; Kang K; Numbers K; Brodaty H; Sachdev P; Kochan NA, 2019, 'Validation and Normative Data for the Modified Telephone Interview for Cognitive Status: The Sydney Memory and Ageing Study', Journal of the American Geriatrics Society, vol. 67, pp. 2108 - 2115, http://dx.doi.org/10.1111/jgs.16033
    Journal articles | 2019
    Lipnicki DM; Makkar SR; Crawford JD; Thalamuthu A; Kochan NA; Lima-Costa MF; Castro-Costa E; Ferri CP; Brayne C; Stephan B; Llibre-Rodriguez JJ; Llibre-Guerra JJ; Valhuerdi-Cepero AJ; Lipton RB; Katz MJ; Derby CA; Ritchie K; Ancelin M-L; Carrière I; Scarmeas N; Yannakoulia M; Hadjigeorgiou GM; Lam L; Chan W-C; Fung A; Guaita A; Vaccaro R; Davin A; Kim KW; Han JW; Suh SW; Riedel-Heller SG; Roehr S; Pabst A; van Boxtel M; Köhler S; Deckers K; Ganguli M; Jacobsen EP; Hughes TF; Anstey KJ; Cherbuin N; Haan MN; Aiello AE; Dang K; Kumagai S; Chen T; Narazaki K; Ng TP; Gao Q; Nyunt MSZ; Scazufca M; Brodaty H; Numbers K; Trollor JN; Meguro K; Yamaguchi S; Ishii H; Lobo A; Lopez-Anton R; Santabárbara J; Leung Y; Lo JW; Popovic G; Sachdev PS, 2019, 'Determinants of cognitive performance and decline in 20 diverse ethno-regional groups: A COSMIC collaboration cohort study', PLOS Medicine, vol. 16, pp. e1002853 - e1002853, http://dx.doi.org/10.1371/journal.pmed.1002853
    Journal articles | 2019
    Numbers KT; Barnier AJ; Harris CB; Meade ML, 2019, 'Ageing stereotypes influence the transmission of false memories in the social contagion paradigm', Memory, vol. 27, pp. 368 - 378, http://dx.doi.org/10.1080/09658211.2018.1511809
    Journal articles | 2014
    Numbers KT; Meade ML; Perga VA, 2014, 'The influences of partner accuracy and partner memory ability on social false memories', Memory and Cognition, vol. 42, pp. 1225 - 1238, http://dx.doi.org/10.3758/s13421-014-0443-9
  • Conference Papers | 2021
    Samtani S; Stevens A; Lipnicki DM; Costa EC; Guerchet M; Preux P-M; Skoog I; Scarmeas N; Kim K-W; Ganguli M; Crowe M; Ng TP; Numbers K; Sachdev PS; Brodaty H, 2021, 'Social Health And Reserve in the Dementia patient journey (SHARED): Females, older adults, and people living with dementia are vulnerable to social isolation', in INTERNATIONAL PSYCHOGERIATRICS, CAMBRIDGE UNIV PRESS, pp. 20 - 21, http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000721315200025&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=891bb5ab6ba270e68a29b250adbe88d1
    Conference Abstracts | 2019
    Lipnicki DM; Trollor JN; Kochan NA; Numbers K; Kang K; Crawford JD; Brodaty H; Sachdev PS, 2019, 'Failure to identify particular odours predicts future dementia and mortality [Abstract O1-02-04]', in Alzheimer's & Dementia, Elsevier BV, Los Angeles, CA, USA, Vol. 15, pp. P195 - P196, presented at Alzheimer's Association International Conference (AAIC) 2019, Los Angeles, CA, USA, 14 July 2019 - 16 July 2019, http://dx.doi.org/10.1016/j.jalz.2019.06.4526
    Preprints |
    Hou J; Hess JL; Armstrong N; Bis JC; Grenier-Boley B; Karlsson IK; Leonenko G; Numbers K; O’Brien EK; Shadrin A; Thalamuthu A; Yang Q; Andreassen OA; Brodaty H; Gatz M; Kochan NA; Lambert J-C; Laws SM; Masters CL; Mather KA; Pedersen NL; Posthuma D; Sachdev PS; Williams J; Fan CC; Faraone SV; Fennema-Notestine C; Lin S-J; Escott-Price V; Holmans P; Seshadri S; Tsuang MT; Kremen WS; Glatt SJ, Polygenic resilience scores capture protective genetic effects for Alzheimer’s disease, http://dx.doi.org/10.1101/2022.05.10.22274858

1. Dementia prevention is the primary focus of my research and a national health care priority in Australia. Although dementia is the second leading cause of death in older Australians, it is estimated that 40% of all dementia cases are preventable through the modification of lifestyle risk factors such as social isolation, diet, and exercise. This is where my research comes in. Specifically, I investigate the mediating role of depression and anxiety on risk factors associated with dementia. Previously it was assumed that the presence of increased neuropsychiatric symptoms in people with dementia was a result of the disease (e.g., increasing loss of autonomy), but it is now known that chronic psychiatric symptoms can play a causative role in the development of dementia pathology; for instance, changes in cortisol associated with depression and anxiety also impacts grey matter brain volumes implicated in many dementias (i.e., hippocampus and prefrontal cortex).

2. My second area of research focus is the intersection between older adults’ subjective experiences of cognitive decline and functional ability and their risk for future dementia. This is an especially important area of ageing and dementia research given subjective cognitive complaints (SCCs) are now considered a very early pre-clinical stage of dementia, meaning SCCs are an important diagnostic tool to facilitate early intervention programs. My recent research examines temporal changes in participant and informant SCCs using latent growth curve analyses to model linear changes in SCC reporting over time. I also examine the relationship between self-report and informant-report (someone who knows the person well) SCCs and utility in predicting dementia. 

3. My research also promotes healthy ageing by supporting individuals with dementia. Unfortunately, all dementias are progressive. However, this should not deny personhood or a maximised quality of life people living with dementia or their care partners. This has become especially relevant in light of the current COVID-19 pandemic and ensuing periods of prolonged lockdowns, which have disproportionately impacted older adults worldwide. I have been heavily involved in research looking at the impact of COVID-19 and social isolation on older adults with and without with dementia. I developed and administered a CHeBA COVID-19 questionnaire to over 400 participants (aged 65 – 103) in 2020, and have collected administered the same questionnaire to older German participants to examine cohort and geographic impacts of the pandemic. I am also an Investigator on a 3-country grant that is harmonising data across Australia, the UK, and the US, to determine factors associated with post-COVID wellbeing in older adults on several dimensions.

4. Finally, I am very actively involved in research and groups that aim to challenge negative stereotypes about ageing and dementia. A compelling body of data has emerged showing negative attitudes towards ageing pose a significant risk to physical health and psychological well-being in later life. For example, older adults with worse attitudes about ageing have poorer physical, cognitive, and mental health, and studies show that individuals who endorse negative ageing attitudes in midlife (~45 years) are at greater risk of developing cardiovascular and Alzheimer’s disease pathology nearly 20 years later (~65 years). Not only do negative ageing attitudes predict worse health outcomes in older adults, but ageism promotes other forms of discrimination including social exclusion from important roles and relationships, which further fosters feelings of isolation and loneliness. This is important because increased isolation and loneliness are related to increased neuropsychiatric symptoms such as depression and anxiety, which in turn can result in cortisol related brain pathology.

I am a current supervisor to 3 Honours students and have previously supervised 6 Honours students (5=HD; 1=D). The majority of my students have, or will, submit first author publications in high-impact journals.

I am also an invited Lecturer and Tutor for Beginnings, Growth and Development B in the Faculty of Medicine.

During my PhD at Macquarie University, I was a head Tutor for the Department of Cognitive Science.

Before moving to Australia to commence my PhD, I was a Lecturer for the Department of Psychology (taught: Social Psychology; History and Systems of Psychology; Judgment and Decision Making) at Montana State University for 4 semesters.