Matthew Dennis Grilli

Matthew Dennis Grilli

Assistant Professor, Psychology
Assistant Professor, Evelyn F Mcknight Brain Institute
Assistant Professor, Neurology
Assistant Professor, Cognitive Science - GIDP
Assistant Professor, BIO5 Institute
Primary Department
Department Affiliations
Contact
(520) 621-7447

Work Summary

Work Summary

My research interests are broadly focused on understanding how and why we store and retrieve memories. The clinical and cognitive neuroscience research conducted in my laboratory combines neuropsychological, cognitive, social psychological, and neuroimaging approaches. An emphasis of my current research is autobiographical memory, which refers to memories of personal experiences. Ongoing projects are investigating how autobiographical memory is affected in several populations, including older adults at risk for Alzheimer’s disease and individuals with acquired brain injury. We also are interested in understanding how changes to autobiographical memory impact other aspects of cognition, and we seek to develop new interventions to improve autobiographical memory and everyday functioning.

Research Interest

Research Interest

My research interests are broadly focused on understanding the reciprocal relations of self and memory. How does the self influence learning and memory retrieval? How does memory contribute to one's sense of self? Uncovering the ways in which the self and memory interact may advance understanding of identity, elucidate the conditions and experiences that modify the self, and inspire clinical interventions that improve quality of life and wellbeing for people who have neurological or mental health conditions. Ongoing projects are investigating how to improve memory through self-referential encoding strategies in individuals with traumatic brain injury and other neuropsychological conditions. My current research also is investigating how individuals with amnesia (a profound learning and memory impairment) construct a sense of self and experience a sense of continuity in life.

Publications

Grilli, M. D., & Glisky, E. L. (2011). The self-imagination effect: benefits of a self-referential encoding strategy on cued recall in memory-impaired individuals with neurological damage. Journal of the International Neuropsychological Society : JINS, 17(5), 929-33.

Knowledge of oneself is preserved in many memory-impaired individuals with neurological damage. Therefore, cognitive strategies that capitalize on mechanisms related to the self may be particularly effective at enhancing memory in this population. The present study investigated the effect of "self-imagining," imagining an event from a personal perspective, on short and long delayed cued recall in memory-impaired individuals with neurological damage. Sixteen patients intentionally encoded word pairs under four separate conditions: visual imagery, semantic elaboration, other person imagining, and self-imagining. The results revealed that self-imagining led to better performance than other-imagining, semantic elaboration, and visual imagery. Furthermore, the "self-imagination effect" (SIE) was preserved after a 30-min delay and was independent of memory functioning. These findings indicate that self-imagining provides a mnemonic advantage in brain-injured individuals, even those with relatively poor memory functioning, and suggest that self-imagining may tap into mnemonic mechanisms related to the self.

Grilli, M. D. (2017). The association of personal semantic memory to identity representations: insight into higher-order networks of autobiographical contents. Memory (Hove, England), 25(10), 1435-1443.

Identity representations are higher-order knowledge structures that organise autobiographical memories on the basis of personality and role-based themes of one's self-concept. In two experiments, the extent to which different types of personal semantic content are reflected in these higher-order networks of memories was investigated. Healthy, young adult participants generated identity representations that varied in remoteness of formation and verbally reflected on these themes in an open-ended narrative task. The narrative responses were scored for retrieval of episodic, experience-near personal semantic and experience-far (i.e., abstract) personal semantic contents. Results revealed that to reflect on remotely formed identity representations, experience-far personal semantic contents were retrieved more than experience-near personal semantic contents. In contrast, to reflect on recently formed identity representations, experience-near personal semantic contents were retrieved more than experience-far personal semantic contents. Although episodic memory contents were retrieved less than both personal semantic content types to reflect on remotely formed identity representations, this content type was retrieved at a similar frequency as experience-far personal semantic content to reflect on recently formed identity representations. These findings indicate that the association of personal semantic content to identity representations is robust and related to time since acquisition of these knowledge structures.

Grilli, M. D., Wank, A. A., & Verfaellie, M. (2017). The Life Stories of Adults with Amnesia: Insights into the Contribution of the MTL to the Higher-Order Organization of Autobiographical Memory. Neuropsychologia.

Autobiographical memories are not stored in isolation but rather are organized into life chapters, higher-order knowledge structures that represent major themes conveying the arc of one's life. Neuropsychological studies have revealed that both episodic memory and some aspects of personal semantic memory are impaired in adults with medial temporal lobe (MTL) damage. However, whether such impairment compromises the retrieval and formation of life chapters is unknown. Therefore, we had 10 adults with MTL amnesia and 20 control participants narrate their life stories, and we extracted life chapters from these narratives using a novel scoring protocol. For the retrograde and anterograde time period separately, we evaluated the number of life chapters and assessed their quality, as indexed by measures of complexity and richness. Additionally, to investigate the idea that formation of life chapters occurs on a protracted time scale, we separated the amnesic participants into an early-life and a later-life onset subgroup. Results revealed that early-onset, but not later-onset, amnesic participants generated fewer retrograde life chapters than controls. The higher-order temporal relation among retrograde chapters, but not their thematic relation or the richness of individual life chapters, was impaired in both amnesic subgroups. The amnesic participants also generated fewer anterograde life chapters than controls, and the richness of their anterograde chapters was reduced in terms of content, but not self-reflection. Findings suggest that the organization of autobiographical content into life chapters is a protracted process that depends on the MTL, as does retrieval of higher order temporal relations among life chapters.

Hou, M., Grilli, M. D., & Glisky, E. L. (2017). Self-reference enhances relational memory in young and older adults. Neuropsychology, development, and cognition. Section B, Aging, neuropsychology and cognition, 1-16.

The present study investigated the influence of self-reference on two kinds of relational memory, internal source memory and associative memory, in young and older adults. Participants encoded object-location word pairs using the strategies of imagination and sentence generation, either with reference to themselves or to a famous other (i.e., George Clooney or Oprah Winfrey). Both young and older adults showed memory benefits in the self-reference conditions compared to other-reference conditions on both tests, and the self-referential effects in older adults were not limited by low memory or executive functioning. These results suggest that self-reference can benefit relational memory in older adults relatively independently of basic memory and executive functions.

Grilli, M. D., & Verfaellie, M. (2015). Supporting the self-concept with memory: insight from amnesia. Social Cognitive and Affective Neuroscience, 10(12), 1684-92.

We investigated the extent to which personal semantic memory supports the self-concept in individuals with medial temporal lobe amnesia and healthy adults. Participants completed eight 'I Am' self-statements. For each of the four highest ranked self-statements, participants completed an open-ended narrative task, during which they provided supporting information indicating why the I Am statement was considered self-descriptive. Participants then completed an episodic probe task, during which they attempted to retrieve six episodic memories for each of these self-statements. Supporting information was scored as episodic, personal semantic or general semantic. In the narrative task, personal semantic memory predominated as self-supporting information in both groups. The amnesic participants generated fewer personal semantic memories than controls to support their self-statements, a deficit that was more pronounced for trait relative to role self-statements. In the episodic probe task, the controls primarily generated unique event memories, but the amnesic participants did not. These findings demonstrate that personal semantic memory, in particular autobiographical fact knowledge, plays a critical role in supporting the self-concept, regardless of the accessibility of episodic memories, and they highlight potential differences in the way traits and roles are supported by personal memory.