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Behavioral states may be associated with distinct spatial patterns in electrocorticogram.

Panagiotides H, Freeman WJ, Holmes MD, Pantazis D - Cogn Neurodyn (2010)

Bottom Line: Moments of maximal spatial variance are shown to cluster by behavior.Comparisons between conditions using a permutation test reveal significantly different spatial patterns for each behavior.We conclude that ECoG recordings obtained on the cortical surface with optimal high spatial frequency resolution reveal distinct local spatial patterns that reflect different behavioral states, and we predict that similar patterns will be found in many if not most cortical areas on which a microgrid is placed.

View Article: PubMed Central - PubMed

ABSTRACT
To determine if behavioral states are associated with unique spatial electrocorticographic (ECoG) patterns, we obtained recordings with a microgrid electrode array applied to the cortical surface of a human subject. The array was constructed with the intent of extracting maximal spatial information by optimizing interelectrode distances. A 34-year-old patient with intractable epilepsy underwent intracranial ECoG monitoring after standard methods failed to reveal localization of seizures. During the 8-day period of invasive recording, in addition to standard clinical electrodes a square 1 × 1 cm microgrid array with 64 electrodes (1.25 mm separation) was placed on the right inferior temporal gyrus. Careful review of video recordings identified four extended naturalistic behaviors: reading, conversing on the telephone, looking at photographs, and face-to-face interactions. ECoG activity recorded with the microgrid that corresponded to these behaviors was collected and ECoG spatial patterns were analyzed. During periods of ECoG selected for analysis, no electrographic seizures or epileptiform patterns were present. Moments of maximal spatial variance are shown to cluster by behavior. Comparisons between conditions using a permutation test reveal significantly different spatial patterns for each behavior. We conclude that ECoG recordings obtained on the cortical surface with optimal high spatial frequency resolution reveal distinct local spatial patterns that reflect different behavioral states, and we predict that similar patterns will be found in many if not most cortical areas on which a microgrid is placed.

No MeSH data available.


Related in: MedlinePlus

Scatter plots of the scores (scoret,1 and scoret,2) of each voltage vector v(t) for the first two principal components. Only time points of maximum local variance were analyzed (t ∈ SM), separately for each condition
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Fig5: Scatter plots of the scores (scoret,1 and scoret,2) of each voltage vector v(t) for the first two principal components. Only time points of maximum local variance were analyzed (t ∈ SM), separately for each condition

Mentions: Microgrid measurements with the highest spatial variance were grouped by condition and separately analyzed with principal component analysis as described in the “Method” section (Eq. 2). Figure 5 shows scatter plots of the scores for the first two principal components (scoret,1 and scoret,2, t ∈ SM) for each condition. In other words, it displays the projections (inner product) of each microgrid measurement v(t) on the first two principal components pc1 and pc2.Fig. 5


Behavioral states may be associated with distinct spatial patterns in electrocorticogram.

Panagiotides H, Freeman WJ, Holmes MD, Pantazis D - Cogn Neurodyn (2010)

Scatter plots of the scores (scoret,1 and scoret,2) of each voltage vector v(t) for the first two principal components. Only time points of maximum local variance were analyzed (t ∈ SM), separately for each condition
© Copyright Policy
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC3045495&req=5

Fig5: Scatter plots of the scores (scoret,1 and scoret,2) of each voltage vector v(t) for the first two principal components. Only time points of maximum local variance were analyzed (t ∈ SM), separately for each condition
Mentions: Microgrid measurements with the highest spatial variance were grouped by condition and separately analyzed with principal component analysis as described in the “Method” section (Eq. 2). Figure 5 shows scatter plots of the scores for the first two principal components (scoret,1 and scoret,2, t ∈ SM) for each condition. In other words, it displays the projections (inner product) of each microgrid measurement v(t) on the first two principal components pc1 and pc2.Fig. 5

Bottom Line: Moments of maximal spatial variance are shown to cluster by behavior.Comparisons between conditions using a permutation test reveal significantly different spatial patterns for each behavior.We conclude that ECoG recordings obtained on the cortical surface with optimal high spatial frequency resolution reveal distinct local spatial patterns that reflect different behavioral states, and we predict that similar patterns will be found in many if not most cortical areas on which a microgrid is placed.

View Article: PubMed Central - PubMed

ABSTRACT
To determine if behavioral states are associated with unique spatial electrocorticographic (ECoG) patterns, we obtained recordings with a microgrid electrode array applied to the cortical surface of a human subject. The array was constructed with the intent of extracting maximal spatial information by optimizing interelectrode distances. A 34-year-old patient with intractable epilepsy underwent intracranial ECoG monitoring after standard methods failed to reveal localization of seizures. During the 8-day period of invasive recording, in addition to standard clinical electrodes a square 1 × 1 cm microgrid array with 64 electrodes (1.25 mm separation) was placed on the right inferior temporal gyrus. Careful review of video recordings identified four extended naturalistic behaviors: reading, conversing on the telephone, looking at photographs, and face-to-face interactions. ECoG activity recorded with the microgrid that corresponded to these behaviors was collected and ECoG spatial patterns were analyzed. During periods of ECoG selected for analysis, no electrographic seizures or epileptiform patterns were present. Moments of maximal spatial variance are shown to cluster by behavior. Comparisons between conditions using a permutation test reveal significantly different spatial patterns for each behavior. We conclude that ECoG recordings obtained on the cortical surface with optimal high spatial frequency resolution reveal distinct local spatial patterns that reflect different behavioral states, and we predict that similar patterns will be found in many if not most cortical areas on which a microgrid is placed.

No MeSH data available.


Related in: MedlinePlus