Prof. Renate Thienel
Priority Centre for Translational Neuroscience & Mental Health Research
University of Newcastle
Title: Differential effects of risperidone vs. haloperidol on brain activation during a working memory task in first episode schizophrenia patients.
Date: Thursday 23rd May 2013, 12-1pm in Keats Reading Room (AVLG17) (video streaming to AV3 in the Ourimbah library)
If you would like to meet with Dr. Thienel, please contact A/Prof Scott Brown (firstname.lastname@example.org).
Abstract: Neurocognitive impairments in schizophrenia are common and clinically relevant. The majority of people diagnosed with schizophrenia will experience a significant decline in global, social and occupational function levels in the course of their illness. Amongst the different cognitive domains, memory impairments in particular are regarded as possible intermediate phenotypes of schizophrenia. I investigated whether haloperidol and risperidone - two neuroleptic drugs with differential receptor binding profiles - show distinct impacts on functional networks mediating working memory. Differential effects of first- and second-generation antipsychotics on cognition have been reported before, however most of the previous results where employing disproportionately high doses of haloperidol, with the associated increased risk of unwanted side effects, such as cognitive impairment and extrapyramidal motor side effects. I compared the functional haemodynamic response during an n-back task in first-episode schizophrenia patients on a comparably low to moderate dose of haloperidol versus risperidone. Risperidone treated patients showed stronger activations than haliperidol patients in a cortical network that has previously been associated with this type of working memory task. As the results were controlled for medication dose, and neither side effects nor co-treatment differed between the groups, the results are not likely to be affected by these confounding factors, but rather reflect the drugs different receptor binding profile, such as their differential mesocortical dopaminergic input, and pro-cholinergic properties. On the basis of the behavioural results these differences in activation might represent adaptive processes in order to maintain a sufficient level of performance on the one hand, whilst on the other hand patient’s slower behavioural performance might rest upon a failure to recruit task-relevant brain areas comparably.
Bio: Dr Renate Thienel who graduated in Germany (B.A. [Hons.] M.Psych. [Research], Ph.D. [Dr. rer. nat.] in 2007) currently holds a University of Newcastle Postdoctoral Research Fellowship and is based at the Priority Centre for Translational Neuroscience & Mental Health Research. Renate is affiliated with the Schizophrenia Research Institute and the Hunter Medical Research Institute and is an active member of the Australasian Society of Psychiatric Research. Her research focuses on the aetiologies and the rehabilitation of schizophrenia by studying event related potentials, functional magnetic resonance imaging, magnetic resonance spectroscopy, and diffusion tensor imaging. Renate collaborates with national and international colleagues on various neuroimaging research projects into schizophrenia, the prediction of transition to psychosis, the shared biological basis of schizophrenia, a genetically high risk population (22q11DS), and a novel neuro-feedback procedure to modify brain perfusion using functional magnetic resonance imaging with applications for neurocognitive rehabilitation in schizophrenia and dementia as well as cerebral stroke. Her strong translational approach also includes the creation of a normative database of electroencephalographically recorded sensory auditory memory function in children and adolescents with great potential as a diagnostic tool for the detection of “at-risk mental state”.