The Journal of Neuroscience, March 2, 2005, ():
Compartment-Resolved Imaging of Activity-Dependent Dynamics of Cortical Blood Volume and Oximetry
J. Neurosci. Vanzetta et al.
25: 2233
HTML Page - index.htslp
Supplemental Figures
Files in this Data Supplement:
- Supplemental Fig. 1
-
Figure S1 (Supplemental Material): Effects of compartment-sample choice on inter-compartmental response differences. To increase the SNR of the measurements, we wanted to test whether the sample-sizes taken for the various compartments could be increased by extending the choice of vessel elements to the whole imaged area, although from the neuronal point of view, our visual stimuli (oriented gratings) did activate only a subset of all orientation columns. For this purpose, the samples of vessel elements chosen to represent each compartment was selected either from the whole imaged area or only from within the activated orientation columns. The results are shown for comparison in panels A, B, C, and D, E, F, respectively. The time-courses obtained following either calculation were extremely similar. Only at 605nm the ordering of the resulting time-courses depended on the chosen calculation. The dynamics of the capillary signal was slightly delayed with respect to the venular one, when the samples were not restricted to the active columns (white ellipse in A, D, lower panels), in agreement with the high degree of localization of capillary oximetric changes with loci of increased neuronal activity. A,D: Reflection signals at 605nm, B,E: fluorescence intensity and C,F: reflection at 570nm. To facilitate timing comparisons, the lower panels display the graphs after normalizing the peak-amplitudes to [0,1]. Line codes: dashed black: arteries, thick gray: arterioles, thin gray: parenchyma, thin black: venules, thick black: veins. To better display the differences between the various compartments’ time-courses, the mean time-course (average over all compartments) was subtracted from each individual compartment’s time-course, for each point in time. The dashed gray line in all panels depicts the true “zero-signal-level”. Note that, due to the convention used in this display, relative to the y=0 line, the dashed gray trace thus corresponds to the sign-inverted mean response (average over all compartments). Errorbars: SEM, obtained from 8 and 16 independent datasets.
- Supplemental Fig. 2
-
Figure S2 (Supplemental Material): Comparison of differential oximetric and CBV maps, obtained exclusively from the early part of the response. Correlation between the various differential CBV maps and the early oximetric map.
Top row: A: Differential map (vertical / horizontal) obtained at 605nm. Clipping range: 0.08%. B: Differential map obtained with fluorescence imaging. Clipping range: 0.1%. The colormap in B was inverted to facilitate comparison with the other panels. C: Differential map obtained at 565nm. Clipping range: 0.25%. All images were averaged from 0.4 to 1.2s after stimulus onset. D,E: Differential maps (vertical / horizontal) obtained during the same time window from another cat at 605 and 570nm. Clipping range: 0.07% and 0.1%, respectively. Middle row: Same as top row, but maps were Gaussian (sigma ~100µm) low-pass filtered to enhance the functional patches over the vascular patterns. As shown by the pseudo-color display, the crosses marking dark and bright patches were deduced from maxima and minima of the oximetric maps (A,D, middle row) and transposed to the identical locations in the other rows, to facilitate comparison between the maps. Bottom row: maps in top row (A, B) were Gaussian low-pass filtered with sigma ~200µm, a value around which most correlations between maps peaked. F: Dependence of the correlation coefficient R (y-axis) between the maps on the sigma-value (x-axis, mm) used for Gaussian low-pass filtering. Solid lines: CBV maps were averaged over the whole duration of the response (shown in the main manuscript, Fig. 10 B and C, bottom row): red: R(fluorescence, 565nm); blue: R(fluorescence, early 605nm); black: R(565nm, early 605nm). Dashed lines: same color-code as for solid lines, but CBV maps were averaged from 0.4 to 1.2s. Dotted lines: correlation between early (0.4-1.2s) and late (1.2-8s) CBV maps: cyan: R(early fluorescence, late fluorescence); green: R(early 565nm, late 565nm). The various CBV differential maps correlated better among themselves than any of them correlated with the early differential map obtained at 605nm. This was true also for the maps obtained from another cat: correlating the early CBV to the early oximetric map (E and D middle row) yielded R=0.58, whereas correlating the early CBV to the late CBV map yielded R=0.66. The late CBV maps used to calculate R are not shown in the figure. Scale-bars: 0.5mm.
