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“ Cerebellar contribution to visuo-attentional alpha rhythm: insights from weightlessness ”

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ABSTRACT

Human brain adaptation in weightlessness follows the necessity to reshape the dynamic integration of the neural information acquired in the new environment. This basic aspect was here studied by the electroencephalogram (EEG) dynamics where oscillatory modulations were measured during a visuo-attentional state preceding a visuo-motor docking task. Astronauts in microgravity conducted the experiment in free-floating aboard the International Space Station, before the space flight and afterwards. We observed stronger power decrease (~ERD: event related desynchronization) of the ~10 Hz oscillation from the occipital-parietal (alpha ERD) to the central areas (mu ERD). Inverse source modelling of the stronger alpha ERD revealed a shift from the posterior cingulate cortex (BA31, from the default mode network) on Earth to the precentral cortex (BA4, primary motor cortex) in weightlessness. We also observed significant contribution of the vestibular network (BA40, BA32, and BA39) and cerebellum (lobule V, VI). We suggest that due to the high demands for the continuous readjustment of an appropriate body posture in free-floating, this visuo-attentional state required more contribution from the motor cortex. The cerebellum and the vestibular network involvement in weightlessness might support the correction signals processing necessary for postural stabilization, and the increased demand to integrate incongruent vestibular information.

No MeSH data available.


Related in: MedlinePlus

Experimental settings.(a) Scheme of task sequences. Note the two main “visuo-attention” and “visuo-motor” periods. (b) ERSP template for one representative subject during one on-ground (Eb) session for EEG electrode C3. Note the blue mu ERD band during the “visuo-attention” reported in this study. (c) Recording set up on Earth and (d) during weightlessness. Note the free-floating.
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f1: Experimental settings.(a) Scheme of task sequences. Note the two main “visuo-attention” and “visuo-motor” periods. (b) ERSP template for one representative subject during one on-ground (Eb) session for EEG electrode C3. Note the blue mu ERD band during the “visuo-attention” reported in this study. (c) Recording set up on Earth and (d) during weightlessness. Note the free-floating.

Mentions: On Earth and in weightlessness, all astronauts showed a power decrease or event-related desynchronization (ERD) in the alpha frequency range with respect to the baseline prior to stimulus onset during the visuo-attentional task. This alpha ERD is indicated in the ERSP template by a blue band centered at 10 Hz (Fig. 1a). Additionally, a beta ERD band appears in the subsequent visuo-motor period. The individual alpha frequency ranges of interest at electrode C3 were: 8–12, 12–16, 8–12, 9–13, 7–11 Hz, for participants A1, A2, A3, A4 and A5 respectively. All astronauts showed stronger alpha ERD in weightlessness (W) (2,01 ± 1.34 μV2/Hz ± s.e.m) with respect to that measured on Earth before (Eb, 1.17 ± 0.99 μV2/Hz, p = 0.005,) and after (Ea, 1.32 ± 1.11 μV2/Hz, p = 0.02) the flight (Fig. 2a, on the left) (single-factor ANOVA test with 3 levels, Bonferroni corrected, F (2, 222) = 5,4047) during the visuo-attentional period. The individual ERD estimations (μV2/Hz ± s.e.m.) were 0.31 ± 0.62, 1.21 ± 0.46, 0.93 ± 1.08, 0.72 ± 0.52, 2,67 ± 1,02 for Eb, 0.64 ± 0.60, 1.73 ± 0.99, 2,88 ± 1.47, 1.21 ± 0.71, 3.59 ± 1.32 for W and 0.29 ± 0.75, 1.28 ± 0.48, 0.92  ± 0.80, 1.08 ± 0.72, 3.07 ± 1,63 for Ea, for A1, A2, A3, A4 and A5, respectively (Fig. 2a, on the right). The observed reinforcement of the alpha ERD for the W condition was not an effect of a one-side significant power spectrum increase in the baseline period. In fact, the absolute power spectrum during the baseline period of the W condition (1,82 ± 2.91 μV2/Hz) did not increase from Eb (2.85 ± 1.54 μV2/Hz), but presented a decreasing (not significant) trend (p = 0.11; F (2,222) = 4,9957). Along the same lines, the absolute power spectrum for the visuo-attentional period was significantly smaller for the W (−0.18 ± 1.80 μV2/Hz) than the Eb (1.7 ± 1.26 μV2/Hz) condition (p = 0.00000; F(2,222) = 20,489). The effect of the alpha ERD reinforcement in the W condition was similarly observed in the baseline-normalized spectrogram measurement, or ERSP (dB), calculated with permutation Holms corrected statistic (p < 0.05) at the C3 electrode (note the darker blue alpha band in the ERSP template of the W condition in Fig. 2b) and on the whole scalp (Fig. 2c). In weightlessness the alpha ERD reinforcement extended from the parietal and occipital areas to the central contralateral areas (mu ERD) throughout the visuo-attentional period (Fig. 2c).


“ Cerebellar contribution to visuo-attentional alpha rhythm: insights from weightlessness ”
Experimental settings.(a) Scheme of task sequences. Note the two main “visuo-attention” and “visuo-motor” periods. (b) ERSP template for one representative subject during one on-ground (Eb) session for EEG electrode C3. Note the blue mu ERD band during the “visuo-attention” reported in this study. (c) Recording set up on Earth and (d) during weightlessness. Note the free-floating.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC5121637&req=5

f1: Experimental settings.(a) Scheme of task sequences. Note the two main “visuo-attention” and “visuo-motor” periods. (b) ERSP template for one representative subject during one on-ground (Eb) session for EEG electrode C3. Note the blue mu ERD band during the “visuo-attention” reported in this study. (c) Recording set up on Earth and (d) during weightlessness. Note the free-floating.
Mentions: On Earth and in weightlessness, all astronauts showed a power decrease or event-related desynchronization (ERD) in the alpha frequency range with respect to the baseline prior to stimulus onset during the visuo-attentional task. This alpha ERD is indicated in the ERSP template by a blue band centered at 10 Hz (Fig. 1a). Additionally, a beta ERD band appears in the subsequent visuo-motor period. The individual alpha frequency ranges of interest at electrode C3 were: 8–12, 12–16, 8–12, 9–13, 7–11 Hz, for participants A1, A2, A3, A4 and A5 respectively. All astronauts showed stronger alpha ERD in weightlessness (W) (2,01 ± 1.34 μV2/Hz ± s.e.m) with respect to that measured on Earth before (Eb, 1.17 ± 0.99 μV2/Hz, p = 0.005,) and after (Ea, 1.32 ± 1.11 μV2/Hz, p = 0.02) the flight (Fig. 2a, on the left) (single-factor ANOVA test with 3 levels, Bonferroni corrected, F (2, 222) = 5,4047) during the visuo-attentional period. The individual ERD estimations (μV2/Hz ± s.e.m.) were 0.31 ± 0.62, 1.21 ± 0.46, 0.93 ± 1.08, 0.72 ± 0.52, 2,67 ± 1,02 for Eb, 0.64 ± 0.60, 1.73 ± 0.99, 2,88 ± 1.47, 1.21 ± 0.71, 3.59 ± 1.32 for W and 0.29 ± 0.75, 1.28 ± 0.48, 0.92  ± 0.80, 1.08 ± 0.72, 3.07 ± 1,63 for Ea, for A1, A2, A3, A4 and A5, respectively (Fig. 2a, on the right). The observed reinforcement of the alpha ERD for the W condition was not an effect of a one-side significant power spectrum increase in the baseline period. In fact, the absolute power spectrum during the baseline period of the W condition (1,82 ± 2.91 μV2/Hz) did not increase from Eb (2.85 ± 1.54 μV2/Hz), but presented a decreasing (not significant) trend (p = 0.11; F (2,222) = 4,9957). Along the same lines, the absolute power spectrum for the visuo-attentional period was significantly smaller for the W (−0.18 ± 1.80 μV2/Hz) than the Eb (1.7 ± 1.26 μV2/Hz) condition (p = 0.00000; F(2,222) = 20,489). The effect of the alpha ERD reinforcement in the W condition was similarly observed in the baseline-normalized spectrogram measurement, or ERSP (dB), calculated with permutation Holms corrected statistic (p < 0.05) at the C3 electrode (note the darker blue alpha band in the ERSP template of the W condition in Fig. 2b) and on the whole scalp (Fig. 2c). In weightlessness the alpha ERD reinforcement extended from the parietal and occipital areas to the central contralateral areas (mu ERD) throughout the visuo-attentional period (Fig. 2c).

View Article: PubMed Central - PubMed

ABSTRACT

Human brain adaptation in weightlessness follows the necessity to reshape the dynamic integration of the neural information acquired in the new environment. This basic aspect was here studied by the electroencephalogram (EEG) dynamics where oscillatory modulations were measured during a visuo-attentional state preceding a visuo-motor docking task. Astronauts in microgravity conducted the experiment in free-floating aboard the International Space Station, before the space flight and afterwards. We observed stronger power decrease (~ERD: event related desynchronization) of the ~10&thinsp;Hz oscillation from the occipital-parietal (alpha ERD) to the central areas (mu ERD). Inverse source modelling of the stronger alpha ERD revealed a shift from the posterior cingulate cortex (BA31, from the default mode network) on Earth to the precentral cortex (BA4, primary motor cortex) in weightlessness. We also observed significant contribution of the vestibular network (BA40, BA32, and BA39) and cerebellum (lobule V, VI). We suggest that due to the high demands for the continuous readjustment of an appropriate body posture in free-floating, this visuo-attentional state required more contribution from the motor cortex. The cerebellum and the vestibular network involvement in weightlessness might support the correction signals processing necessary for postural stabilization, and the increased demand to integrate incongruent vestibular information.

No MeSH data available.


Related in: MedlinePlus