Semantic plasticity across timescales in the human brain

Опубликована: Авг. 14, 2024

Our representations of the world need to be stable enough support general knowledge but flexible incorporate new information as our environment changes. How does human brain manage this stability-plasticity trade-off? We analyzed a large dataset in which participants viewed objects embedded thousands natural scenes across many fMRI sessions. Semantic item were located by jointly leveraging voxelwise encoding model find reliable and word-embedding evaluate semantic content. Within medial temporal lobe, hippocampal subfield CA1, parahippocampal cortex, perirhinal cortex gradually drifted period multiple months. Whole-brain analyses revealed gradient plasticity with drift more evident anterior than posterior areas. On short timescales, rapid was observed only such that co-occurrence statistics warped within single session. Together, results suggest solves trade-off through regions.

Язык: Английский

Object Feature Memory Is Distorted by Category Structure

Open Mind, Год журнала: 2024, Номер 8, С. 1348 - 1368

Опубликована: Янв. 1, 2024

Memory systems constantly confront the challenge of capturing both shared features that connect experiences together and unique distinguish them. Across two experiments, we leveraged a color memory distortion paradigm to investigate how handle this representational tension when learning new information. Over thirty-minute period, participants learned categories novel objects, where each feature was assigned particular color. While did not differ in accurately they remembered these overall, inaccurate, misremembered (relative unique) as more similar category's average color, suggesting integration memory. This same rapid warping manifested neural network model trained on categories. The work reveals memories for different are rapidly differentially warped function their roles category.

Язык: Английский