Schedule of Events | Symposia

Intracranial neural dynamics of recognition memory in the lateral parietal cortex of the developing brain

Poster Session B - Sunday, March 30, 2025, 8:00 – 10:00 am EDT, Back Bay Ballroom/Republic Ballroom

Joseph P. Kelly¹ (josephkelly1@northwestern.edu), Adam J. O. Dede¹, Samantha M. Gray², Qin Yin^3,4, Parisa Vahidi³, Eishi Asano⁴, Olivia Kim McManus⁵, Shifteh Sattar⁵, Jack J. Lin⁶, Joyce Y. Wu^1,7, Sandi K. Lam^1,7, Jeffrey S. Raskin^1,7, Stephan U. Schuele¹, Joshua M. Rosenow¹, Ammar Shaikhouni⁸, Peter Brunner⁹, Jarod L. Roland^9,10, Kurtis I. Auguste¹¹, Robert T. Knight¹², Noa Ofen^3,4, Elizabeth L. Johnson¹; ¹Northwestern University Feinberg School of Medicine, ²Stanford University, ³Wayne State University, ⁴University of Texas at Dallas, ⁵University of California, San Diego, and UCSD Rady Children’s Hospital, ⁶University of California, Davis, ⁷Ann & Robert H. Lurie Children’s Hospital of Chicago, ⁸Ohio State University and Nationwide Children’s Hospital, ⁹Washington University in St. Louis, ¹⁰St. Louis Children’s Hospital, ¹¹University of California, San Francisco, and UCSF Benioff Children’s Hospital, ¹²University of California, Berkeley

Lateral parietal cortex (LPC) contains functionally heterogeneous sub-regions, including interdigitated task-activated and task-deactivated sites, that support attention and memory. It is unknown how sub-regional neural dynamics support memory encoding and retrieval in children, and whether age-related variability in these dynamics corresponds with age-related variability in memory. Here, we analyzed intracranial EEG (iEEG) data from the supramarginal gyrus (SMG), angular gyrus (AG), and superior parietal cortex (SPC: superior parietal lobule, intraparietal sulcus) of 44 neurosurgical epilepsy patients aged 5-30 years (18 females) who performed an old/new scene recognition task. Trial-by-trial iEEG data from the encoding and retrieval phases of the task were analyzed as a function of retrieval success (remembered trials vs. forgotten trials). All sub-regions contained interdigitated task-activated and task-deactivated channels (% activated/deactivated: SMG=54/31, AG=59/38, SPC=46/43). Successful encoding was associated with decreased high-frequency broadband activity (HFA, 70–150 Hz) in task-activated SPC channels at stimulus onset (<0.2 s), and increased HFA in task-deactivated SMG channels late in the trial (2.6–2.7 s). Successful retrieval was associated with sustained HFA decreases in task-deactivated SPC (0–1.5 s) and AG channels (1.0–1.5 s). Importantly, memory performance improved by age (r=.31, p=.04), and initial results suggest that memory-related deactivations in AG increase with age (r=.56, p=.07). Data collection is ongoing. These results identify signatures of memory encoding and retrieval in the developing LPC, highlight the importance of task-deactivated LPC regions, and ground further developmental investigations of low-frequency dynamics, connectivity, and LPC structure as they relate to memory development.

Topic Area: LONG-TERM MEMORY: Development & aging