As scientist-practitioners, our research contributes to evidence-based clinical neuropsychology and to the advancement of cognitive neuroscience knowledge. Central themes include research in Parkinson’s disease, epilepsy, cognitive neuroscience of hippocampal functions, and interprofessional collaborations.
Cognitive decline is common but heterogeneous in Parkinson’s disease and following neurosurgical treatments such as Deep Brain Stimulation (DBS). Our work aims at characterizing this heterogeneity and at identifying individuals who are at a heightened vulnerability. Specifically, we examine cognitive dysfunction outside the classic dopamine-related, frontostriatal circuits.
Some specific examples include:
Examining whether hippocampally-dependent episodic memory and related neuroimaging markers predict cognitive outcome.
Examining the relationship between cognitive decline and cholinergic basal forebrain degeneration.
Characterizing episodic and semantic memory without the influence of executive dysfunction.
Characterizing social cognitive abilities and their relationship to social functioning and quality of life.
Examining potential threats to the validity of clinical tools such as the impact of multiculturalism.
Lastly, we have active collaborations with several medical specialties on projects investigating the role of the basal ganglia in cognition, and the cognitive effects of neuromodulation parameters.
We have known for decades that individuals with temporal-lobe epilepsy can have impairments in memory and language function and that surgery to treat medication-refractory epilepsy can exacerbate those deficits or engender new ones. Traditional neuropsychology in epilepsy focuses on standardized clinical tests and specific neural substrates such as the hippocampus or anterior temporal neocortex. Our approach attempts to leverage novel paradigms from cognitive neuroscience, with a particular focus on imaging brain networks, to gain greater insight into the nature of these deficits and individual differences in treatment outcomes.
Some specific examples include:
Assessment of autobiographical memory, which reveals altered pathways for retrieving life events and profound deficits even when other forms of episodic memory are generally intact.
Identification of promoters and neural substrates of accelerated long-term forgetting (poor hippocampal-neocortical interaction, failure of benefit of sleep-related consolidation processes).
Examining cognitive resilience to surgery based on features of the non-resected components of language and memory networks.
In addition, some of our work pertains to the development of interventions targeting memory and well-being in people living with epilepsy.
Cognitive Neuroscience of Hippocampal Functions
The hippocampus and related brain networks are critical to episodic memory, but their specific roles remain to be elucidated. We consider the soundest evidence to reflect convergence of patient or lesion studies and neuroimaging studies in healthy individuals.
Some of our recent work includes:
Demonstrating that the different contributions of anterior and posterior hippocampus to memory depend on tasks, hemispheres, and connectivity patterns.
Examining the interplay between the hippocampus and the cholinergic basal forebrain across different episodic memory paradigms as predicted by computational models.
Beyond episodic memory, we also investigate the involvement of the hippocampal network in other aspects of cognition, such as social cognition and pain perception.
Cognition is relevant to many areas of medical research and we collaborate with various specialties including Neurology, Neurosurgery, Neurophysiology, Neuroradiology, Anesthesia, and Occupational Therapy. Generally, our role is to select or devise appropriate cognitive tasks to assess the outcome or side-effects of therapies, the cognitive correlates of novel brain imaging biomarkers, or to investigate cognitive abilities in other clinical populations. We also provide assistance with the development of new instruments.