# Brain dynamics of lexical retrieval after left hemisphere stroke

> **NIH NIH R21** · SAN DIEGO STATE UNIVERSITY · 2021 · $149,599

## Abstract

Brain dynamics supporting lexical retrieval after left hemisphere stroke
This proposal examines the brain dynamics supporting lexical retrieval in patients with chronic stroke-induced
aphasia due to left-hemisphere (LH) lesions. Patients presenting with stroke-induced aphasia due to LH
damage often experience major lexical retrieval difficulties. Lexical retrieval abilities are, however, not equally
compromised in these patients. One possible explanation for this variability is that lexical retrieval requires
multiple cognitive components that are subserved by different neural regions. In particular, patients with
lesions to the left lateral prefrontal cortex (LPFC) can often immediately recognize the word they are trying to
say when given a choice between a few options or the onset of the target word. Patients with lesions in the left
posterior temporal cortex (pLTC) may have trouble recognizing the correct word even when it is given to them.
The LPFC and pLTC may therefore play different roles in subprocesses of lexical retrieval, lexical activation and
selection, and brain network reorganization may consequently be different after LPFC versus pLTC stroke-
induced lesions. Domain-general cognitive control processes have been proposed to play a role in recovery
from stroke-induced aphasia. However, the degree to which domain-general cognitive control mechanisms are
engaged in lexical retrieval following LH stroke is unclear. This project seeks to shed light on these issues. In
particular, the proposed research will examine the spatio-temporal dynamics supporting lexical retrieval
following LH stroke when lesions encompass the LPFC versus the pLTC, and how domain-general cognitive
control may be engaged. Our main hypothesis is that patients with lesions encompassing the LPFC
but not the pLTC will show more efficient engagement of domain-general cognitive control
mechanisms in lexical retrieval than patients with lesions encompassing the pLTC. A combination
of novel theoretical and methodological approaches will be used along with well-established tasks that assess
lexical retrieval and domain-general cognitive control. Aim 1 will investigate the impact of damage to the LPFC
versus pLTC on lexical retrieval to infer the causal roles of these regions in lexical activation and selection using
established and novel behavioral modeling. Aim 2 will determine if and when domain-general cognitive
control PFC regions are involved in lexical retrieval in patients with LPFC or pLTC lesions in comparison with
matched-controls using spatially-enhanced scalp electroencephalography (EEG). Finally, Aim 3 will examine
if differences in lexical retrieval abilities between these groups are subserved by differences in brain
connectivity using EEG-derived functional connectivity measures. The personal and societal cost caused by
lexical retrieval disruption after stroke is considerable. The results of these studies will provide a key step
toward understanding brain d...

## Key facts

- **NIH application ID:** 10236338
- **Project number:** 5R21DC016985-03
- **Recipient organization:** SAN DIEGO STATE UNIVERSITY
- **Principal Investigator:** Stephanie Ries-Cornou
- **Activity code:** R21 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2021
- **Award amount:** $149,599
- **Award type:** 5
- **Project period:** 2019-09-01 → 2023-08-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10236338

## Citation

> US National Institutes of Health, RePORTER application 10236338, Brain dynamics of lexical retrieval after left hemisphere stroke (5R21DC016985-03). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10236338. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*