1. Figure 1. Characterization of the 4 states of vigilance
Figure 1. Characterization of the 4 states of vigilance. Wakefulness (A, B, E, F) was defined by a desynchronization ECoG activity in the motor cortex (A, B top traces) and somato-sensory cortex (A, B bottom traces) with the presence of a predominant theta (5–9 Hz), beta (15–30 Hz) and gamma (30–80 Hz) frequency bands activities (E, F) associated with a sustained muscular tonus on EMGs (A, B middle traces). Movement periods (A, E) were defined by sustained motor activity associated with variations of the EMG amplitude. During resting periods (B, F), rats were completely still but alert and a tonic but stable muscular activity was noted on EMGs. SWS (C, G) was defined by a high amplitude activity with predominant delta (1–4 Hz) and alpha (10–14 Hz) frequency bands activities, a decrease of rhythms above 20 Hz and a weak EMG activity (C, middle trace). PS (D, H) was defined by an awake-like ECoG activity with essentially theta and beta rhythms but with the absence of EMG activity (D, middle trace). Scale bars in A (horizontal: 1 s; vertical: 200 μV) apply to B, C, and D. Arrows in E, F, G, and H indicate the loss of power due to the 50-Hz notch filter.
From: Chronic but not Acute Dopaminergic Transmission Interruption Promotes a Progressive Increase in Cortical Beta Frequency Synchronization: Relationships to Vigilance State and Akinesia
Cereb Cortex. 2008;19(7): doi: /cercor/bhn199
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2. Figure 2. Histological controls of the nigral dopamine denervation extent. Photomicrographs of TH immunoreactivity at the SNC (left and right columns) and VTA (middle column) levels in sham-operated (A), unilaterally (B), and bilaterally (C) SNC-lesioned rats. Note the sparing of the DA cell bodies in the VTA in both unilaterally (B) and bilaterally (C) lesioned animals and the complete loss of SNC DA cell bodies above the substantia nigra pars reticulata in B3, C1, and C3. Scale bar in A1 (200 μm) applies in A, B, and C. Asterisks (*) indicate the loss of DA cell bodies in the 6-OHDA-lesioned SNCs. SNR: substantia nigra pars reticulata.
From: Chronic but not Acute Dopaminergic Transmission Interruption Promotes a Progressive Increase in Cortical Beta Frequency Synchronization: Relationships to Vigilance State and Akinesia
Cereb Cortex. 2008;19(7): doi: /cercor/bhn199
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3. Figure 3. Effects of SNC lesion on motor performance measured using the circular corridor (A), the grid (B), and the bar (C) tests. As assessed using the circular corridor test (A), unilateral and bilateral SNC lesions induced a marked and stable akinesia as soon as day 1 for bilaterally lesioned and day 2 for unilaterally lesioned rats (P < 0.05). Compared with sham and unilaterally operated animals, bilaterally SNC-lesioned ones were also strongly impaired in the grid (B) and bar (C) tests. It is noteworthy that the correct score observed for the unilaterally SNC-lesioned rats in the grid and bar tests is due to unilateral movements allowed by the intact hemisphere. White bars: sham-operated animals; gray and black bars: unilaterally and bilaterally 6-OHDA-lesioned rats, respectively.
From: Chronic but not Acute Dopaminergic Transmission Interruption Promotes a Progressive Increase in Cortical Beta Frequency Synchronization: Relationships to Vigilance State and Akinesia
Cereb Cortex. 2008;19(7): doi: /cercor/bhn199
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4. Figure 4. Spectral analysis (left and middle columns) and coherence (right column) of ECoG signals recorded in the motor and somato-sensory cortices during movement period in sham (A; n = 3 rats), unilaterally (B; n = 4 rats) and bilaterally (C; n = 4 rats) SNC-lesioned animals. (A1, B1, C1) Power spectrogram of the ECoG activity recorded in the motor cortex. (A2, B2, C2) Power spectrogram of the ECoG activity recorded in the somato-sensory cortex. (A3, B3, C3) Coherence between ECoG activities recorded in the motor and somato-sensory cortices. Note particularly in (B) the progressive increase in the power of the beta frequency band that is accompanied by an increase in the coherence between activities of motor and somato-sensory cortices. In the present and Figures 5, 6, 7, 10 the power and the coherence levels are graduated from black (lowest level) to white (highest level). White lines on the power spectrum maps (left and middle columns) delimit areas presenting statistically significant difference in power compared with sham condition (P < 0.05 Mann–Whitney U after Bonferroni correction). White lines on coherence maps (right column) delimit areas where coherence between the motor and the somato-sensory cortices is statistically higher than what is expected from random fluctuations (P < 0.05 in one-tailed t-test after Bonferroni correction).
From: Chronic but not Acute Dopaminergic Transmission Interruption Promotes a Progressive Increase in Cortical Beta Frequency Synchronization: Relationships to Vigilance State and Akinesia
Cereb Cortex. 2008;19(7): doi: /cercor/bhn199
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5. Figure 5. Spectral analysis (left and middle columns) and coherence (right column) of ECoG signals recorded in the motor and somato-sensory cortices at rest in sham (A; n = 3 rats), unilaterally (B; n = 4 rats), and bilaterally (C; n = 4 rats) SNC-lesioned animals. (A1, B1, C1) Power spectrogram of the ECoG activity recorded in the motor cortex. (A2, B2, C2) Power spectrogram of the ECoG activity recorded in the somato-sensory cortex. (A3, B3, C3) Coherence between ECoG activities recorded in the motor and somato-sensory cortices. Note particularly in (B) the progressive increase in the power of the β frequency band that is accompanied by an increase in the coherence between activities of motor and somato-sensory cortices. White lines: see legend of Figure 4.
From: Chronic but not Acute Dopaminergic Transmission Interruption Promotes a Progressive Increase in Cortical Beta Frequency Synchronization: Relationships to Vigilance State and Akinesia
Cereb Cortex. 2008;19(7): doi: /cercor/bhn199
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6. Figure 6. Spectral analysis (left and middle columns) and coherence (right column) of ECoG signals recorded in the motor and somato-sensory cortices during SWS in sham (A; n = 3 rats), unilaterally (B; n = 4 rats) and bilaterally (C; n = 4 rats) SNC-lesioned animals. (A1, B1, C1) Power spectrogram of the ECoG activity recorded in the motor cortex. (A2, B2, C2) Power spectrogram of the ECoG activity recorded in the somato-sensory cortex. (A3, B3, C3) Coherence between ECoG activities recorded in the motor and somato-sensory cortices. Note the lack of synchronization and coherence in the β frequency band in this state. White lines: see legend of Figure 4.
From: Chronic but not Acute Dopaminergic Transmission Interruption Promotes a Progressive Increase in Cortical Beta Frequency Synchronization: Relationships to Vigilance State and Akinesia
Cereb Cortex. 2008;19(7): doi: /cercor/bhn199
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7. Figure 7. Spectral analysis (left and middle columns) and coherence (right column) of ECoG signals recorded in the motor and somato-sensory cortices during PS in sham (A; n = 3 rats), unilaterally (B; n = 4 rats), and bilaterally (C; n = 4 rats) SNC-lesioned animals. (A1, B1, C1) Power spectrogram of the ECoG activity recorded in the motor cortex. (A2, B2, C2) Power spectrogram of the ECoG activity recorded in the somato-sensory cortex. (A3, B3, C3) Coherence between ECoG activities recorded in the motor and somato-sensory cortices. Note the emergence of a nonexcessive β synchronization in the unilateral situation and of a coherence between activities of motor and somato-sensory cortices with the recovery of the PS. White lines: see legend of Figure 4.
From: Chronic but not Acute Dopaminergic Transmission Interruption Promotes a Progressive Increase in Cortical Beta Frequency Synchronization: Relationships to Vigilance State and Akinesia
Cereb Cortex. 2008;19(7): doi: /cercor/bhn199
Cereb Cortex | © The Author Published by Oxford University Press. All rights reserved. For permissions, please

8. Figure 8. Spectral analysis comparing the coherence of activities between motor and somato-sensory cortices across the different groups (sham [n = 3 rats], unilaterally [n = 4 rats], and bilaterally [n = 4 rats]) SNC-lesioned rats and in the different vigilance state. (A) Unilateral lesion vs. sham; (B) bilateral lesion vs. sham; (C) bilateral vs. unilateral lesion. (A1, B1, C1) movement period; (A2, B2, C2) resting period; (A3, B3, C3) SWS; (A4, B4, C4) PS. Plots of coherence report the values of coherence (which by construction take values between 0 and 1) estimated from different groups. White lines on coherence maps delimit areas presenting statistically significant difference between motor and somato-sensory cortices: unilateral lesion versus sham (left column), bilateral lesion vs. sham (middle column) and bilateral lesion vs. unilateral lesion (right column) (P < 0.05 in one-tailed t-test after Bonferroni correction). Note that during wakefulness and PS, unilaterally lesioned animals present a higher coherence between motor and somato-sensory cortices compared with sham and bilaterally lesioned animals.
From: Chronic but not Acute Dopaminergic Transmission Interruption Promotes a Progressive Increase in Cortical Beta Frequency Synchronization: Relationships to Vigilance State and Akinesia
Cereb Cortex. 2008;19(7): doi: /cercor/bhn199
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9. Figure 10. Effects of chronic treatment by neuroleptic on motor performance (A, B) and on ECoG spectrograms recorded during wakefulness (C, D). As assessed using the circular corridor test (A), the bar (B, white bars) and grid (B, gray bars) tests, chronic neuroleptic treatment induced a marked and stable akinesia as soon as day 1 following the first neuroleptic injection (P < 0.05). The spectral analysis of ECoG signals recorded during movement (C) and resting (D) periods in the motor (C1, D1) and somato-sensory (C2, D2) cortices shows the emergence of an excessive β synchronization growing progressively along the course of the neuroleptic treatment. M: movement periods; R: resting periods. White lines: see legend of Figure 4 concerning power spectrum maps.
From: Chronic but not Acute Dopaminergic Transmission Interruption Promotes a Progressive Increase in Cortical Beta Frequency Synchronization: Relationships to Vigilance State and Akinesia
Cereb Cortex. 2008;19(7): doi: /cercor/bhn199
Cereb Cortex | © The Author Published by Oxford University Press. All rights reserved. For permissions, please

10. Figure 9. Power spectrum of ECoG in the 10- to 45-Hz frequency band in sham, unilaterally, bilaterally SNC-lesioned rats and following acute neuroleptics (n = 3 rats) injection observed in awake resting animals. Note that acute neuroleptics injection has no effect in motor (left) and somato-sensory (right) cortices. For comparative purpose, the traces in the sham, unilaterally and bilaterally lesioned animals correspond to those obtained at day 28. NL: neuroleptics.
From: Chronic but not Acute Dopaminergic Transmission Interruption Promotes a Progressive Increase in Cortical Beta Frequency Synchronization: Relationships to Vigilance State and Akinesia
Cereb Cortex. 2008;19(7): doi: /cercor/bhn199
Cereb Cortex | © The Author Published by Oxford University Press. All rights reserved. For permissions, please