Mouse BOLD fMRI at ultrahigh field detects somatosensory networks including thalamic nuclei.
Neuroimage
; 195: 203-214, 2019 07 15.
Article
em En
| MEDLINE
| ID: mdl-30946950
ABSTRACT
Forepaw somatosensory stimulation induces neural activities in relay thalamic nuclei, the primary somatosensory cortex of forelimb (S1FL), and the secondary somatosensory cortex (S2). However, rodent fMRI studies of somatosensory stimulation have commonly reported BOLD changes only in S1FL, which may be due to side effects of anesthetics and/or the low sensitivity in the thalamus. Thus, we have obtained mouse BOLD fMRI under newly-adopted ketamine-xylazine anesthesia. High-resolution BOLD fMRI obtained with same imaging parameters at 9.4T versus 15.2T shows the improvement of functional detectability byâ¯≥â¯2 times at 15.2T due to higher signal intensity and larger BOLD response. The fMRI responses at 15.2T were robustly observed at well-known somatosensory networks including thalamus. Second, echo-time-dependent BOLD signals are dominant based on multi-echo fMRI data. A ratio of BOLD responses in S1FL to thalamus is â¼2, which is not related to different baseline T2∗ or different cerebral blood volume. Third, group-averaged 15.2T BOLD maps show activities in S1FL, S2, motor cortices, and thalamic nuclei, which agree well with neural tracing network data from the Allen Institute, demonstrating that fMRI detects entire somatosensory networks. Our data suggest that ultrahigh field fMRI provides a unique window into understanding functional networks in normal and transgenic mouse models noninvasively.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Núcleos Talâmicos
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Mapeamento Encefálico
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Imageamento por Ressonância Magnética
Limite:
Animals
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article