Asaf Gilboa | University of Toronto | Rotman Research Institute at Baycrest
Prior knowledge and its influence on new learning and memory: A cognitive neuroscience perspective
Common wisdom as well as cognitive and educational psychology have long identified the influential role of prior knowledge on encoding and retrieval of new knowledge. Two forms of such knowledge have traditionally been the focus of cognitive psychology research: conceptual knowledge and schemas. Cognitive neuroscience has primarily investigated the neural substrates of conceptual knowledge and its influence on new learning. More recently schemas have also generated interest in both the animal and human cognitive neuroscience literature.
Being highly complex knowledge structures, schemas have always posed significant theoretical and experimental challenges to cognitive scientists. Bartlett (1932) was the first to introduce the concept of schema into the memory domain, after it had been used for a couple of decades in the domains of sensory perception and developmental psychology. Curiously, even Bartlett expressed significant reservations about the use of the term, proclaiming it poorly captured key characteristics of memory schemas as he viewed them, most notably their adaptability and dynamic nature. Thus, while the influence of prior knowledge on the constructive and reconstructive nature of memory has never been doubted, reservations were expressed about the utility and precise meaning of schema itself as a psychological and neurobiological construct.Over the past century schemas have intermittently appeared in cognitive psychology, only to later fall out of favor, arguably due to poor theoretical constraints of the term.
In the present lecture I will review some of the recent and exciting findings on the neurobiology of schema in the memory domain, arising from animal, lesion and neuroimaging investigations. Importantly the presentation will be geared towards elucidating the use of the term schema and delineating its relationship to other related terms- most notably concepts, but also scripts, gist, extracted probabilities and so forth. The discussion will focus on essential properties of schema including interconnectivity, nested structures, extracted commonalities, adaptability and chronology. Their cognitive and neurobiological functions including scaffolding of information assimilation, directing attentional resources, enabling inferential elaboration, facilitating orderly memory searches, editing and summarizing of new information and supporting reconstruction of missing information from memory will be discussed. Data from patients with neurological damage (confabulation and amnesia), and neuroimaging (fMRI and ERP’s) will be presented. Neuroanatomically, I will suggest that the same principle of representational hubs that bind together isolated neural modules into multi-modal ensembles operate for different mnemonic reconstructions. The medial temporal lobe (MTL) and hippocampus is a hub for episodic memories, the anterior temporal lobe (ATL) is a hub for conceptual knowledge end the ventromedial prefrontal cortex (vmPFC) is a hub for schemas. Facilitation of encoding of new information by prior schemas can be mediated by vmPFC interaction with the hippocampus and posterior neocortex, but the possibility of hippocampal-independent learning under certain conditions will also be explored.
Dr. Asaf Gilboa, Ph.D.
I completed my undergraduate studies at the Hebrew University in Jerusalem, majoring in Psychology and the Amirim inter-disciplinary program. I received my M.A. degree in Clinical Neuropsychology from the Hebrew University in Jerusalem where I studied the neurocognitive effects of Posttraumatic Stress Disorder (PTSD) and Traumatic Brain Injury (TBI). I received my Ph.D. in Psychology and Neuroscience from the University of Toronto, where I studied the cognitive neuroscience of remote memory. I then pursued postdoctoral studies at the Rotman Research Institute in Toronto focusing on prefrontal contributions to memory monitoring and control. I was a Lecturer and Senior Lecturer at Haifa University in Israel where I also served as co-director of the Clinical Neuropsychology program. I am currently a Scientist at the Rotman Research Institute at Baycrest and the Centre for Stroke Recovery as well as an Assistant Professor in Psychology at the University of Toronto. Together with my lab members I investigate neurological and neuropsychiatric aspects of memory disorders. Our research focuses on memory disorders such as amnesia, dementia and confabulation, employing various methodologies (lesion analysis, fMRI, Skin conductance, ERP and MEG) to investigate of the mechanisms underlying these disorders. I have co-authored over 40 articles and book chapters, and have received several awards including the Dusty and Ettie Miller Fellowship for Outstanding Young Scholars and the Donald T. Stuss Award for Research Excellence.