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Different Mode of Afferents Determines the Frequency Range of High Frequency Activities in the Human Brain: Direct Electrocorticographic Comparison between Peripheral Nerve and Direct Cortical Stimulation.

Kobayashi K, Matsumoto R, Matsuhashi M, Usami K, Shimotake A, Kunieda T, Kikuchi T, Mikuni N, Miyamoto S, Fukuyama H, Takahashi R, Ikeda A - PLoS ONE (2015)

Bottom Line: We evaluated the HFA power values in reference to the baseline overriding N20 (earliest cortical response) and N80 (late response) of somatosensory evoked potentials (HFA(SEP(N20)) and HFA(SEP(N80))) and compared those overriding N1 and N2 (first and second responses) of cortico-cortical evoked potentials (HFA(CCEP(N1)) and HFA(CCEP(N2))).HFA(SEP(N20)) showed the power peak in the frequency above 200 Hz, while HFA(CCEP(N1)) had its power peak in the frequency below 200 Hz.Since HFA(CCEP(N1)) and HFA induced during various brain functions share a similar broadband profile of the power spectrum, cortico-coritcal horizontal propagation seems to represent common mode of neural transmission for processing these functions.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurology, Kyoto University Graduate School of Medicine, Kyoto, Japan.

ABSTRACT
Physiological high frequency activities (HFA) are related to various brain functions. Factors, however, regulating its frequency have not been well elucidated in humans. To validate the hypothesis that different propagation modes (thalamo-cortical vs. cortico-coritcal projections), or different terminal layers (layer IV vs. layer II/III) affect its frequency, we, in the primary somatosensory cortex (SI), compared HFAs induced by median nerve stimulation with those induced by electrical stimulation of the cortex connecting to SI. We employed 6 patients who underwent chronic subdural electrode implantation for presurgical evaluation. We evaluated the HFA power values in reference to the baseline overriding N20 (earliest cortical response) and N80 (late response) of somatosensory evoked potentials (HFA(SEP(N20)) and HFA(SEP(N80))) and compared those overriding N1 and N2 (first and second responses) of cortico-cortical evoked potentials (HFA(CCEP(N1)) and HFA(CCEP(N2))). HFA(SEP(N20)) showed the power peak in the frequency above 200 Hz, while HFA(CCEP(N1)) had its power peak in the frequency below 200 Hz. Different propagation modes and/or different terminal layers seemed to determine HFA frequency. Since HFA(CCEP(N1)) and HFA induced during various brain functions share a similar broadband profile of the power spectrum, cortico-coritcal horizontal propagation seems to represent common mode of neural transmission for processing these functions.

No MeSH data available.


Related in: MedlinePlus

The distributions of logarithmic power values in reference to the baseline in each frequency band.As for the 4 groups, HFASEP(N20) (a black solid line), HFACCEP(N1) (a grey solid line), HFASEP(N80) (a black dashed line) and HFACCEP(N2) (a grey dashed line), all the power values of 7 hemispheres are averaged (mean ± SE). RM-ANOVA showed statistically significant interactions between the 4 groups. An asterisk indicates significant interaction between the 2 groups in the post-hoc analysis. Other conventions are the same as for Fig 3.
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pone.0130461.g004: The distributions of logarithmic power values in reference to the baseline in each frequency band.As for the 4 groups, HFASEP(N20) (a black solid line), HFACCEP(N1) (a grey solid line), HFASEP(N80) (a black dashed line) and HFACCEP(N2) (a grey dashed line), all the power values of 7 hemispheres are averaged (mean ± SE). RM-ANOVA showed statistically significant interactions between the 4 groups. An asterisk indicates significant interaction between the 2 groups in the post-hoc analysis. Other conventions are the same as for Fig 3.

Mentions: In order to compare the power trend across the frequency bands among HFASEP(N20), HFASEP(N80), HFACCEP(N1), and HFACCEP(N2), we also drew additional figures plotting the change of the logarithmic power spectra across the frequency bands at the timing of N1 and N2 of CCEP and N20 and N80 of SEP. In each patient, we analyzed the power values for frequency bands centered at 80, 160, 240, 320, 400, 480, and 560 Hz for the 4 groups (HFASEP(N20), HFASEP(N80), HFACCEP(N1), HFACCEP(N2)). After the plot was made for each patient (see Fig 3G, 3H, 3I and 3J), all the power values from 7 hemispheres in 6 patients (N = 7 for HFASEP(N20) and HFASEP(N80), N = 16 for HFACCEP(N1) and HFACCEP(N2)) were plotted in the same figure (see Fig 4).


Different Mode of Afferents Determines the Frequency Range of High Frequency Activities in the Human Brain: Direct Electrocorticographic Comparison between Peripheral Nerve and Direct Cortical Stimulation.

Kobayashi K, Matsumoto R, Matsuhashi M, Usami K, Shimotake A, Kunieda T, Kikuchi T, Mikuni N, Miyamoto S, Fukuyama H, Takahashi R, Ikeda A - PLoS ONE (2015)

The distributions of logarithmic power values in reference to the baseline in each frequency band.As for the 4 groups, HFASEP(N20) (a black solid line), HFACCEP(N1) (a grey solid line), HFASEP(N80) (a black dashed line) and HFACCEP(N2) (a grey dashed line), all the power values of 7 hemispheres are averaged (mean ± SE). RM-ANOVA showed statistically significant interactions between the 4 groups. An asterisk indicates significant interaction between the 2 groups in the post-hoc analysis. Other conventions are the same as for Fig 3.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4472671&req=5

pone.0130461.g004: The distributions of logarithmic power values in reference to the baseline in each frequency band.As for the 4 groups, HFASEP(N20) (a black solid line), HFACCEP(N1) (a grey solid line), HFASEP(N80) (a black dashed line) and HFACCEP(N2) (a grey dashed line), all the power values of 7 hemispheres are averaged (mean ± SE). RM-ANOVA showed statistically significant interactions between the 4 groups. An asterisk indicates significant interaction between the 2 groups in the post-hoc analysis. Other conventions are the same as for Fig 3.
Mentions: In order to compare the power trend across the frequency bands among HFASEP(N20), HFASEP(N80), HFACCEP(N1), and HFACCEP(N2), we also drew additional figures plotting the change of the logarithmic power spectra across the frequency bands at the timing of N1 and N2 of CCEP and N20 and N80 of SEP. In each patient, we analyzed the power values for frequency bands centered at 80, 160, 240, 320, 400, 480, and 560 Hz for the 4 groups (HFASEP(N20), HFASEP(N80), HFACCEP(N1), HFACCEP(N2)). After the plot was made for each patient (see Fig 3G, 3H, 3I and 3J), all the power values from 7 hemispheres in 6 patients (N = 7 for HFASEP(N20) and HFASEP(N80), N = 16 for HFACCEP(N1) and HFACCEP(N2)) were plotted in the same figure (see Fig 4).

Bottom Line: We evaluated the HFA power values in reference to the baseline overriding N20 (earliest cortical response) and N80 (late response) of somatosensory evoked potentials (HFA(SEP(N20)) and HFA(SEP(N80))) and compared those overriding N1 and N2 (first and second responses) of cortico-cortical evoked potentials (HFA(CCEP(N1)) and HFA(CCEP(N2))).HFA(SEP(N20)) showed the power peak in the frequency above 200 Hz, while HFA(CCEP(N1)) had its power peak in the frequency below 200 Hz.Since HFA(CCEP(N1)) and HFA induced during various brain functions share a similar broadband profile of the power spectrum, cortico-coritcal horizontal propagation seems to represent common mode of neural transmission for processing these functions.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurology, Kyoto University Graduate School of Medicine, Kyoto, Japan.

ABSTRACT
Physiological high frequency activities (HFA) are related to various brain functions. Factors, however, regulating its frequency have not been well elucidated in humans. To validate the hypothesis that different propagation modes (thalamo-cortical vs. cortico-coritcal projections), or different terminal layers (layer IV vs. layer II/III) affect its frequency, we, in the primary somatosensory cortex (SI), compared HFAs induced by median nerve stimulation with those induced by electrical stimulation of the cortex connecting to SI. We employed 6 patients who underwent chronic subdural electrode implantation for presurgical evaluation. We evaluated the HFA power values in reference to the baseline overriding N20 (earliest cortical response) and N80 (late response) of somatosensory evoked potentials (HFA(SEP(N20)) and HFA(SEP(N80))) and compared those overriding N1 and N2 (first and second responses) of cortico-cortical evoked potentials (HFA(CCEP(N1)) and HFA(CCEP(N2))). HFA(SEP(N20)) showed the power peak in the frequency above 200 Hz, while HFA(CCEP(N1)) had its power peak in the frequency below 200 Hz. Different propagation modes and/or different terminal layers seemed to determine HFA frequency. Since HFA(CCEP(N1)) and HFA induced during various brain functions share a similar broadband profile of the power spectrum, cortico-coritcal horizontal propagation seems to represent common mode of neural transmission for processing these functions.

No MeSH data available.


Related in: MedlinePlus