Spontaneous Eye Blink Rate (EBR) Is Uncorrelated with Dopamine D2 Receptor Availability and Unmodulated by Dopamine Agonism in Healthy Adults.
Journal Article (Journal Article)
Spontaneous eye blink rate (EBR) has been proposed as a noninvasive, inexpensive marker of dopamine functioning. Support for a relation between EBR and dopamine function comes from observations that EBR is altered in populations with dopamine dysfunction and EBR changes under a dopaminergic manipulation. However, the evidence across the literature is inconsistent and incomplete. A direct correlation between EBR and dopamine function has so far been observed only in nonhuman animals. Given significant interest in using EBR as a proxy for dopamine function, this study aimed to verify a direct association in healthy, human adults. Here we measured EBR in healthy human subjects whose dopamine D2 receptor (DRD2) availability was assessed with positron emission tomography (PET)-[18F]fallypride to examine the predictive power of EBR for DRD2 availability. Effects of the dopamine agonist bromocriptine on EBR also were examined to determine the responsiveness of EBR to dopaminergic stimulation and, in light of the hypothesized inverted-U profile of dopamine effects, the role of DRD2 availability in EBR responsivity to bromocriptine. Results from 20 subjects (age 33.6 ± 7.6 years, 9F) showed no relation between EBR and DRD2 availability. EBR also was not responsive to dopaminergic stimulation by bromocriptine, and individual differences in DRD2 availability did not modulate EBR responsivity to bromocriptine. Given that EBR is hypothesized to be particularly sensitive to DRD2 function, these findings suggest caution in using EBR as a proxy for dopamine function in healthy humans.
Full Text
Duke Authors
Cited Authors
- Dang, LC; Samanez-Larkin, GR; Castrellon, JJ; Perkins, SF; Cowan, RL; Newhouse, PA; Zald, DH
Published Date
- September 2017
Published In
Volume / Issue
- 4 / 5
Start / End Page
- ENEURO.0211 - ENEU17.2017
PubMed ID
- 28929131
Pubmed Central ID
- PMC5602106
Electronic International Standard Serial Number (EISSN)
- 2373-2822
International Standard Serial Number (ISSN)
- 2373-2822
Digital Object Identifier (DOI)
- 10.1523/eneuro.0211-17.2017
Language
- eng