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Research Projects


NEURAL BASES OF COGNITIVE AND BEHAVIOURAL EFFECTS OF FASD

PI: Professor S W Jacobson & Professor N Gaab 

The study will use neuroimaging to examine neural correlates of reading impairment in children with Fetal Alcohol Spectrum Disorders (FASD). During the first two years of the study, 163 adolescents, age 14-15 years, will each receive two scanning sessions on the same day. We plan to bring two children to the scanner on one day and to book a 4-hour slot, so that the first child can have lunch and a break during the second child’s first session, and the second child can have a break when the first child is scanned for the second time.

During the last three years of the study, 177 preschool children will receive scanning – they will only be in the scanner for one imaging session.


COMBATING CRAVING WITH CONTINGENCY MANAGEMENT: Neuroplasticity and methamphetamine abuse in South Africa

PI: Dr Samantha Brooks

Funded by: National Institute of Health

This study will correlate MA-abstinence outcomes from an 8-week contingency management (CM) program of voucher- based incentives using an escalating schedule that has been successfully implemented as an adjunct to MA treatment by our collaborators in the United States. Pre- and post- treatment neuroimaging and neurocognitive assessments will assist in identifying structures and/or processes that may represent targets for development of novel behavioral and/or medication therapies.


COGNITIVE TRAINING IN PATIENTS WITH OBSESSIVE-COMPULSIVE DISORDER 

PI: Dr Samantha Brooks

It is currently unclear whether cognitive training using a working memory task, is effective in reducing obsessive-compulsive symptoms and neuropsychological deficits in patients with OCD. This project will involve an intervention consisting of 8 weeks of cognitive training.  Working memory, neuropsychological functioning and OCD symptomatology will be assessed pre and post-treatment. Furthermore neuroimaging using sMRI and fMRI will be conducted at baseline as well as at the end of the 8 week period.  The scan will serve to show any structural or functional changes in the frontostriatal area involved with working memory. To our knowledge, this is one of the first studies to date to examine whether cognitive training improves symptoms in OCD.  


METHINF

PI: Assoc Professor Kirsty Donald

Funded by: NRF & US Developmental Grant 

This research project aims to show how non-invasive (DTI, MRI and fMRI) neuroimaging and 3D-facial imaging may identify FASD-related brain abnormalities, before clinical symptoms of FASD are recognizable. This research project will also observe long-term effects of alcohol-exposure on the developing brain from birth to 2-years old. 

Currently, very little research data exists regarding the impact of prenatal alcohol exposure in this early childhood period. During this period, higher-level brain networks have not yet been established and external environmental influences have not yet made a significant impact, however, the brain is developing rapidly at this time, with significant changes occurring in the structural and functional networks of the brain. Therefore, making this a critical time in brain development.

This project aims to work towards detection and identification of early warning signs for a possible FASD diagnosis. An early diagnosis will allow for early interventions and treatment plans to be setup, and this will open a window of opportunity for prevention or reduction of symptom severity in children with FASD.


SADFDG - Social Anxiety Disorder 

PI: Dr Alex Doruyter

Funded by: Ntembi Brain Receptors

In collaboration with the MRC Unit on Anxiety and Stress Disorders (Universities of Stellenbosch and Cape Town) the Division of Nuclear Medicine (Stellenbosch University) is currently performing research on functional networks in Social Anxiety Disorder (SAD). The project aims to correlate metabolic imaging findings (using F-18 FDG PET/CT) and functional MR imaging, with various social cognition measures. The project is designed to identify differences in the way that patients with SAD process social information and the functional neural correlates of these disturbances. SAD participants undergo repeat measures after an 8-week course of moclobemide therapy to investigate for treatment effect. Both people with SAD and healthy controls are currently being recruited for this project (further details on www.sadstudy.co.za under “Current Projects”).


HIV 9 YEAR  

PI: Professor E. Meintjes, AJW. van der  Kouwe & B. Laughton 

Funded by: National institute of Child Health and Human Development USA, DST, NRF & UCT

Longitudinal Neuroimaging and Cognitive Study of HIV-Infected Children 

Most children born with HIV live in sub-Saharan Africa. With increased access to antiretroviral therapy (ART), these children are surviving longer with chronic HIV infection. There is a concomitant increase in cognitive deficits and impaired brain development by the time the children reach school age. In this longitudinal project, we will study a cohort of children that have been followed since birth at the ages of 7 and 9 years with cognitive testing and structural, diffusion and spectroscopic brain imaging to establish the effects of HIV and ART during this important period of brain development. The project builds on a collaboration between the Universities of Stellenbosch and Cape Town and the Massachusetts General Hospital, building data analysis infrastructure and MR imaging technology for collecting, analyzing, and interpreting pediatric imaging data. We hope that a better understanding of brain development in these children will help to guide treatment strategies even in resource-limited settings where MRI is not available.


PTSD - Post traumatic stress disorder 

PI: Ms Sheri Koopowitz

Funded by: The Drakenstein Child Health Study

Neuroimaging PTSD and MDD women in a South African community setting 

This research looks at a Posttraumatic stress disorder (PTSD) and major depressive disorder (MDD) in a cohort of women. WOmen with PTSD, MDD and PTSD + MDD are scanned using resting-state MRI as well as fMRI.

The aim is to determine how PTSD, and MDD, affect the structure and function of certain brain regions associated with the disorders, as well as to determine any functional differences between the two disorders. Resting-state networks will also be compared between the groups. This study is part of a larger, more comprehensive study, the Drakenstein Child Health Study. 


EXERCISE TRIAL

PI: Dr Julia Goedecke

Funded by: NRF Competitive Programme for Rated Research

Mechanisms underlying insulin resistance in black SA women: Lessons from an exercise intervention.

We have previously shown that black South African (SA) women are more insulin resistant (IR) than their white   counterparts, and hyersecrete insulin to maintain normoglycaemia.  However, with increasing age, insulin secretion in black SA women decreases and is associated with type 2 diabetes (T2D).

The aim is to examine the mechanisms underlying the changes in insulin sensitivity and secretion in response to a 12-week aerobic exercise intervention in obese black SA women.


GAMBLING DISORDER

PI: Professor Christine Lochner

Funded by: Biological Psychiatry 

The MRC Unit on Anxiety and Stress Disorders from the Universities of Stellenbosch and Cape Town is currently conducting a study on gambling disorder (GD) aimed at better understanding the causality, symptomatology and neurobiologiucal underpinnings of this condition.

Specifically, the study covers clinical aspects of GD (e.g. the symptoms, illness severity and the impact on their quality of life), the structure and functioning of certain brain regions implicated in this condition, and participants’ thinking patterns and emotional responses, as determined by structural and functional magnetic resonance imaging (fMRI), and a neurocognitive battery, respectively.

The study also aims to find out more about the role of specific polymorphisms in certain candidate genes (the hereditary material) that contribute to the development of GD via analysis of candidate genes of patients from South Africa.

This study is nestled in a larger project, i.e. a comprehensive collaborative study by researchers at the US and UCT using genotyping procedures, neurocognitive assessments and neuroimaging sequences to investigate compulsivity and impulsivity in patients with GD, substance (i.e. methamphetamine) use disorder or obsessive-compulsive disorder.


HANDGRIP/N-BACK

PI: DR Laurie Rauch

Funded by:  NRF Thuthuka Research Funding

The aim is to evaluate the influence of methylphenidate (MPH) ingestion on neural mechanisms in obese individuals and ultra-endurance athletes - during a series of fatiguing handgrip exercises and an N-back cognitive test - and compare these to the neural mechanisms of the same participants, during the same series of fatiguing handgrip exercises and N-back test, without ingesting MPH.
 
The objective of this research is three-fold

1.    To determine if there are differences in the neural regulation of fatigue between groups previously associated with dopamine receptor differences.

2.    To examine differences in the neural regulation response to MPH between obese and normal weight population groups and between groups with high physical activity levels and low physical activity levels.

3.    To determine if there are differences in the neural regulation of executive control between groups previously associated with dopamine receptor differences.


EFFECTS OF ALCOHOL ABUSE ON THE BRAIN

PI: Dr Georgina Spies

A pilot study assessing the effects of alcohol abuse on the brain in the context of earlier ART-initiation among HIV positive individuals.

The aim is to investigate the longitudinal effects of earlier ART initiation on brain structure and cognitive functioning, describe the association between HIV and alcohol use disorders (AUD) on regional brain volume changes and concomitant neuropsychological test performance, and examine the association between HIV-infection variables (e.g. HIV onset age, CD4 cell count, CD4 nadir, viral load) and regional brain volume changes in HIV-infected individuals with and without alcohol abuse/dependence.

Men and women will be recruited from clinics and communities in the Western Cape where ART is currently available at different CD4 thresholds. We will assess participants using a 2 x 2 comparative design on the variables of CD4 at initiation and alcohol use. The pilot sample will therefore consist of early initiators (CD4 > 500) and late initiators (CD4 < 350), with and without an alcohol use disorder (AUD). All participants will undergo neuromedical, neuropsychological, and neuroimaging assessments at baseline and at 6 months follow-up.


ENIGMA Collaboration on HIV, OCD, Anxiety Disorders

PI:  Professor Dan Stein

Funded by:  NIH and MRC


NEUROCOGNITIVE AND NEUROIMAGING EFFECTS OF HEAVY EPISODIC DRINKING (HED) IN HIV 

PI:    Mr Jonathon Ipser

Funded by:  NRF and MRC

This Pilot project aims to provide baseline data on the impact on HED on neurocognitive deficits associated with HIV infection in ARV-naive individuals, as well as the individual and combined impact  of heavy alcohol use and HIV on various measuers of brain integrity, with an emphasis on executive functioning networks. A secondary objective to this study is to compare commonly employed cut-off scores on self-rated drinking screens with levels of the ethanol metabolite ethyl glucuronide (EtG) in hair, to help determine the relative sensitivity of these measures in identifying neurocognitive and neuroimaging abnormalities in HIV and HED.


SHARED ROOTS

PI:    Professor S Seedat

Funded by: MRC

The overarching aim of SHARED ROOTS is to interrogate genomic, neural, cellular and environmental signatures that are common to neuropsychiatric disorders (NPDs) and cardiovascular disease (CVD) risk, as defined by the metabolic syndrome (MetS), and that contribute to co-morbidity, symptom severity, and treatment outcomes. This is being done using an innovative, multi-omics, systems-biology approach that combines genomic, transcriptomic, epigenetics and complementary phenotypic and multimodal neuroimaging data, to identify and disentangle biological, environmental, and behavioural pathways that lead to the development of comorbidity of these disorders. Recruitment is on-going for the targeted 600 patients with NPDs, half of whom will meet criteria for metabolic syndrome (MetS).

The specific aims are to:

  1. Identify global cellular pathways or a 'genetic signature' that increases risk for developing NPDs and comorbid MetS
  2. Investigate differences in gene expression between NPD individuals with/out the comorbid MetS
  3. Assess differences in DNA methylation between NPD individuals with/out comorbid MetS
  4. Evaluate structural and functional neuro-circuitry differences in NPD individuals with/out comorbid MetS
  5. Generate a computational/statistical model to develop a more holistic understanding of these complex phenotypes.

STUDY ON FREQUENCY, MANAGEMENT AND OUTCOMES OF DIFFUSE MYOCARDIAL FIBROSIS IN HIV-ASSOCIATED CARDIOMYOPATHY 

PI: Dr Ntobeko Ntusi 

Patients with HIV infection have inflammation of the heart muscle which may lead to scarring of fibrosis. We would like to assess the frequency of scarring in the heart muscle in HIV-infected patients, as assessed by MRI and also to see what effect antiretroviral therapy and common blood pressure medication have on improving or preventing this fibrosis. Finally, we are also interested to assess the relationship of myocardial scarring on MRI with cardiovascular outcomes.


INVESTIGATION OF EFFECT OF DISEASE ACTIVITY ON VASCULAR AND CARDIAC STRUCTURE AND FUNCTION IN TAKAYASU'S ARTHRITIS, SYSTEMIC LUPUS ERYTHEMATOSUS AND RHEUMATOID ARTHRITIS USING MULTIPARAMETRIC CARDIOVASCULAR MAGNETIC RESONANCE 

PI: Dr Ntobeko Ntusi 

Patients with autoimmune diseases and inflammatory arthritis, which includes conditions like Takayasu’s arteritis, systemic lupus erythematosus and rheumatoid arthritis are more likely to develop heart disease and blood vessel stiffness. In these patients, inflammation, causing soreness and redness of the joints, may also affect the heart and blood vessels through blood-borne substances. The purpose of the study is to use cardiovascular magnetic resonance imaging (MRI) to study the nature and frequency of heart and blood vessel disease in people with these conditions, to understand mechanisms of disease and outcomes.


STUDY ON FREQUENCY, MANAGEMENT AND OUTCOMES OF INFECTIVE ENDOCARDITIS 

PI: Dr Ntobeko Ntusi 

Patients with infective endocarditis have inflammation of the heart which may lead to scarring or fibrosis, valve dysfunction and heart failure. We would like to assess the frequency of scarring in the heart muscle in infective endocarditis patients, as assessed by MRI. Additionally, we are also interested to assess the relationship of myocardial scarring on MRI with cardiovascular outcomes.


INTRAINDIVIDUAL VARIABILITY IN THE PROGRESSION OF ALZHEIMER'S DISEASE: A LONGITUDINAL TRAJECTORY OF COGNITIVE DECLINE 

PI: Associate Professor Kevin G. F. Thomas

Research description: The study tracks cognitive decline in the progression of Alzheimer's disease (AD) over the course of 12 months using measures of within-person performance variability (intraindividual variability (IIV)). A central goal of the research is to improve prognostic estimates of AD progression (i.e. rate of decline, trajectory, etc.) and to improve statistical modelling of cognitive change data in AD research by using IIV-based non-linear statistical analyses (e.g. dynamical systems modelling). The magnetic resonance imaging (MRI) component of the study aims to investigate the neuropathological processes that underlie the rate of progression in AD and the mechanisms of IIV.


CHER 11

PI: Professor E. Meintjes, AJW. van der  Kouwe & B. Laughton 

Funded by: National institute of Child Health and Human Development USA, DST, NRF & UCT

Longitudinal Neuroimaging and Cognitive Study of HIV-Infected Children  Most children born with HIV live in sub-Saharan Africa. With increased access to antiretroviral therapy (ART), these children are surviving longer with chronic HIV infection. There is a concomitant increase in cognitive deficits and impaired brain development by the time the children reach school age. In this longitudinal project, we will study a cohort of children that have been followed since birth at the ages of 7 and 9 years with cognitive testing and structural, diffusion and spectroscopic brain imaging to establish the effects of HIV and ART during this important period of brain development. The project builds on a collaboration between the Universities of Stellenbosch and Cape Town and the Massachusetts General Hospital, building data analysis infrastructure and MR imaging technology for collecting, analyzing, and interpreting pediatric imaging data. We hope that a better understanding of brain development in these children will help to guide treatment strategies even in resource-limited settings where MRI is not available.


CAPE TOWN ADOLESCENT ANTIRETROVIRAL COHORT (CTAAC)

PI: Prof Heather Zar & A/Prof Jackie Hoare

Funded by: NIH R01


MODELLING NEUROINFLAMMATION IN SCHIZOPHRENIA: A MAGNETIC RESONANCE IMAGING, ELECTROENCEPHALOGRAPHY AND CYTOKINE STUDY (MODNISZ)

PI: Dr Fleur Howells

Funded by: MRC


CROSS CULTURAL NEUROIMAGING OF EMOTION IN SOUTH AFRICA, NETHERLANDS AND JAPAN

PI: Dr Ruud Hortensius

This research is part of a large international collaboration between researchers in South Africa, the Netherlands and Japan. In this project, we are trying to understand hpw sociocultural factors affect neural, behavioral and autonomic response using cross-cultural neuroimaging and psychophysiological tools.


THE EFFECT OF SOMATOSENSORY EXERCISE PROGRAM ON BRAIN ACTIVATION AND FUNCTIONAL RECOVERY IN CHRONIC STROKE SURVIVORS

PI: Ms Tania Gregory

Funded by: Thuthuka NRF

A randomised crossover experimental study, this study will only include individuals who had first-ever ischemic stroke more than 6 months ago as well as those who have hemiparesis after their stroke.

 


CARDIOVASCULAR MAGNETIC RESONANCE CHARACTERISATION OF THE PHENOTYPE OF REFRACTORY HYPERTENSION

PI: Dr Ntobeko Ntusi

Funded by: ADA and Bertie Levenstein

There is a paucity of data on RHTN and its association to CVD and ultimately mortality in the African population. Furthermore, the prevalence of this disease has not yet been identified in the sub-Saharan African region considering that CVD is said to be among the top 3 causes of death in this region. This study hopes to define the phenotype and imaging characteristics of RHTN and controlled hypertension in patients using CMR.

Our findings may contribute to improved understanding of the pathophysiology of this disease in the African population and may point to a need for development of more effective treatment suited individual genotypes within this population. The aim of this study is to identify patients with refractory hypertension and compare phenotypes in these patients to controlled hypertensives and the normal population.


HIV MyFi

PI: Dr Ntobeko Ntusi

Funded by: American Heart Association, Minneapolis Medical Research Foundation

A case control study of 50 HIV positive (ARV treated) and 50 HIV negative patients over age 40. We are assessing the frequency scarring in the myocardium in HIV-infected patients and seeing what effect ARV and common blood pressure medications have on improving or preventing this fibrosis.


CHARACTERISATION OF PHENOTYPES OF INFLAMMATION, FIBROSIS AND REMODELLING IN CHRONIC RHEUMATIC HEART DISEASE USING MULTI-PARAMETRIC CARDIOVASCULAR MAGNETIC RESONANCE

PI: Prof Ntobeko Ntusi

Funded by: NRF

Using multi-parametric CMR, we aim to characterise the phenotypes of inflammatory disease in rheumatic diseased individuals. In this study, we shall be stratifying the phenotypes of cardiovascular involvement in rheumatic heart disease. i.e. using CMR to assess global LV systolic function and LV myocardial strain and torsion. Aside that, we shall also evaluate LV fibrosis (LGE, T1, T2 mapping, ECV), LV inflammation and Haemodynamics in 50 RHD patients which shall be matched with 50 healthy patients.