Dr. Derek Fisher

Dr. Fisher’s research program can roughly be divided into two streams: 1) ERP-indexed changes in brain function in mental illness, with an emphasis on schizophrenia and psychosis, and; 2) neuropsychopharmacology, or how drugs alter brain function. In the first of these streams, Fisher has predominantly examined brain-based deficits across the schizophrenia spectrum using EEG and ERPs and, following the Research Domain Criteria (RDoC) framework endorsed by the National Institutes of Health, how individual symptoms and syndromes within psychosis are related to neurophysiological change. While this work initially considered chronic schizophrenia, producing several publications (e.g. Fisher et al., 2008a; Fisher et al., 2012; Fisher et al., 2014), Fisher has since established strong research ties with the Nova Scotia Early Psychosis Program (NSEPP) and its director, Dr. Philip Tibbo. This partnership has since yielded several small internal grants through MSVU, the Department of Psychiatry at Dalhousie University and the Nova Scotia Health Authority that have allowed the investigation of changes in early cognitive processing in early psychosis (e.g. Rudolph et al., 2015; Fisher et al., 2018; Fisher et al., 2019), as well as a current large-scale grant from the Nova Scotia Health Research Foundation (now Research NS) that will investigate the utility of ERPs as biomarkers to predict conversion to schizophrenia in high-risk populations. This work has the potential to identify those at greatest risk and, potentially, direct interventions to prevent the onset of psychosis. The use of EEG (vs. other neuroimaging methods such as fMRI) is critical to this work as, if a biomarker can be identified, this will allow for more widespread application of this finding to clinical practice; simply, there are more EEG systems than fMRI or PET scanners throughout the country, particularly in rural areas, allowing a greater number of people to potentially be assessed.

The second major research arm uses EEG and ERPs to investigate how common drugs influence brain function in healthy control and clinical populations. While this work initially focused on nicotine (e.g. Fisher et al., 2010b; Fisher et al., 2013), since establishing his own laboratory we shifted his focus to other drugs, such as caffeine. The lab recently completed a funded project investigating the impact of caffeine on ERP-indexed cognition in early phase psychosis and is currently conducting an NSERC Discovery Grant-funded project probing how caffeine may differentially affect brain function in females across different phases of the menstrual cycle. This latter project, apart from contributing to ongoing work to reverse the systematic exclusion of females from psychopharmacological studies, will provide important insights into the interaction between sex hormones (i.e. estradiol & progesterone) and caffeine in altering cognitive function.

Dr. Fisher’s Faculty Webpage

Selected Articles

Fisher, D.J., Salisbury, D.F. (2019). The neurophysiology of schizophrenia: Current update and future directions. International Journal of Psychophysiology, 145, 1-4. doi: 10.1016/j.ijpsycho.2019.08.005

Fisher, D.J., Rudolph, E.D., Ells, E.M.L., Knott, V.J., Labelle, A., Tibbo, P.G. (2019). Mismatch negativity-indexed auditory change detection of speech sounds in early and chronic schizophrenia. Psychiatry Research: Neuroimaging, 287, 1-9. doi: 10.1016/j.pscychresns.2019.03.010

Riel, H., Lee, J.B., Fisher, D.J., Tibbo, P.G. (2019). Sex differences in ERP waveforms of primary psychotic disorders: A systematic review. International Journal of Psychophysiology, 145, 119-124. doi: 10.1016/j.ijpsycho.2019.02.006

Rudolph, E.D., Ells, E.M.L., Campbell, D.J., Abriel, S.C., Tibbo, P.G., Salisbury, D.F., Fisher, D.J. (2015). Finding the missing stimulus mismatch negativity (MMN) in early psychosis: Altered MMN to violations of an auditory gestalt. Schizophrenia Research, 166, 158-163. doi:10.1016/j.schres.2015.05.028

Fisher, D.J., Smith, D.M., Labelle, A., Knott, V.J. (2014). Attenuation of mismatch negativity (MMN) and novelty P300 in schizophrenia patients with auditory hallucinations experiencing acute exacerbation of illness. Biological Psychology, 100, 43-49. doi:10.1016/j.biopsycho.2014.05.005

Fisher, D.J., Labelle, A., & Knott, V.J. (2008). The right profile: Mismatch negativity in schizophrenia with and without auditory hallucinations as measured by a multi-feature paradigm. Clinical Neurophysiology, 119, 909-921

Dr. Christine Lackner

Dr. Lackner received her Master’s degree at Queen’s University under the direction of Dr. Mark Sabbagh, and her doctorate degree in Behavioural Neuroscience at Brock University under the direction of Dr. Sidney Segalowitz, an internationally recognized electrophysiologist. She is an assistant professor in the Psychology department, and holds adjunct status at Brock University.

Dr. Lackner’s research focus is on understanding individual differences in self-regulation of behaviour and cognition across childhood, adolescence, and young adulthood using a neuroscientific and behavioural approach. Her research helps to address calls to increase research efforts aimed at understanding variations in this important skill set over time and as a function of perturbations to early environments (e.g. Adverse Childhood Experiences). One potential contributor to poor self-regulation is the relative immaturity of the prefrontal cortex into emerging adulthood, which can be indexed through electrophysiological and behavioural measures of attention allocation and inhibitory control. To address her specific research questions, she utilizes EEG, lab-administered tasks, and questionnaire approaches in both typically developing and clinical populations (e.g., adolescents with cerebral palsy, attention-deficit hyperactivity disorder). She has received tri-council funding to support both her doctoral studies (NSERC) and her ongoing program of research (SSHRC). She is actively involved in large research projects funded by national (e.g.,CIHR) and provincial (e.g., Ontario Brain Institute) funding bodies.

Dr. Lackner welcomes inquiries from strong students at all levels interested in developmental neuroscience who wish to become involved in research. These may include undergraduate students from Psychology, Child and Youth Study, and Biology; or graduate students in School Psychology or the Research Master of Arts program.

Dr. Lackner’s Faculty Webpage

Selected Articles

Lackner, C., Gorter, J. W., Segalowitz, S. J., & MyStory Study Group. (2020, advance online publication). Cognitive event-related potentials in young adults with cerebral palsy: A proof of concept study. Clinical EEG and Neuroscience,https://doi.org/10.1177/1550059420977318.

Klymkiw, D., Milligan, K., Lackner, C., Phillips, M., Schmidt, L. A., & Segalowitz, S. J. (2020). Does anxiety enhance or hinder attentional and impulse control in youth with ADHD? An ERP analysis. Journal of Attention Disorders, 24(12), 1746–1756. doi: 10.1177/1087054717707297

Milligan, K., Sibalis, A., McKeough, T., Lackner, C., Schmidt, L., Pun, C. & Segalowitz, S. J. (2019).Impact of mindfulness martial arts training on neural and behavioral indices of attention in youth with learning disabilities and co-occurring mental health challenges. Mindfulness, 10(10), 2152-2164. doi: 10.1007/s12671-019-01161-3

Lackner, C. L., Santesso, D. L., Dywan, J., O’Leary, D., Wade, T. L., & Segalowitz, S. J. (2018).Adverse childhood experiences are associated with self-regulation and the magnitude of the ERN difference. Biological Psychology, 132, 244-251. doi: 10.1016/j.biopsycho.2018.01.006.

Lackner, C., & Martini, T. (2017). Helping University students succeed at employment interviews: The role of self-reflection in e-portfolios. Teaching & Learning Inquiry, 5(2), 3–15. doi: 10.20343/teachlearninqu.5.2.2,

Marshall, B., Lackner, C., Marriot, P., Santesso, D. L., & Segalowitz, S. J. (2014). Using phase shift Granger causality to measure effective connectivity in EEG recordings. Brain Connectivity, 4(10), 826–841. doi: 10.1089/brain.2014.0241

Lackner, C., Santesso, D. L., Dywan, J., Wade, T. L., & Segalowitz, S. J. (2014). ERPs elicited to performance feedback in high-shy and low-shy adolescents. Infant and Child Development, 23(3), 283–294. doi: 10.1002/icd.1865.

Lackner, C., Marshall, W. J., Santesso, D. L., Dywan, J., Wade, T. L., & Segalowitz, S. J. (2014). Adolescent anxiety and aggression can be differentially predicted by electrocortical phase reset variables.  Brain and Cognition, 89, 90–98. doi: 10.1016/j.bandc.2013.10.004

Lackner, C., Santesso, D. L., Dywan, J., Wade, T. L., & Segalowitz, S. J. (2013). Electrocortical indices of selective attention predict adolescent executive functioning. Biological Psychology, 93, 325–333. doi: 10.1016/j.biopsycho.2013.03.001

Lackner, C., Sabbagh, M. A., Liu, X., Holden, J. & Hallinan, L. (2012). Dopamine receptor D4 gene variation predicts preschoolers’ developing theory of mind. Developmental Science, 15(2), 272–280. doi: 10.1111/j.1467-7687.2011.01124.x

Lackner, C., Bowman, L, & Sabbagh, M. (2010). Dopaminergic functioning and preschoolers’ theory of mind. Neuropsychologia, 48(6), 1767–1774. doi: 10.1016/j.neuropsychologia.2010.02.027