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Cognitive modulation of local and callosal neural interactions in decision making.

Merchant H, Crowe DA, Fortes AF, Georgopoulos AP - Front Neurosci (2014)

Bottom Line: They were observed both within area 7a of the posterior parietal cortex and between symmetric 7a areas of the two hemispheres.Time lags for maximum interactions were longer for opposite- vs. same-hemisphere recordings, and lags for negative interactions were longer than for positive interactions in both recording sites.These findings underscore the involvement of dynamic neuronal interactions in cognitive processing within and across hemispheres.

View Article: PubMed Central - PubMed

Affiliation: Department of Behavioral and Cognitive Neurobiology, Instituto de Neurobiología, UNAM Querétaro, México.

ABSTRACT
Traditionally, the neurophysiological mechanisms of cognitive processing have been investigated at the single cell level. Here we show that the dynamic, millisecond-by-millisecond, interactions between neuronal events measured by local field potentials are modulated in an orderly fashion by key task variables of a space categorization task performed by monkeys. These interactions were stronger during periods of higher cognitive load and varied in sign (positive, negative). They were observed both within area 7a of the posterior parietal cortex and between symmetric 7a areas of the two hemispheres. Time lags for maximum interactions were longer for opposite- vs. same-hemisphere recordings, and lags for negative interactions were longer than for positive interactions in both recording sites. These findings underscore the involvement of dynamic neuronal interactions in cognitive processing within and across hemispheres. They also provide accurate estimates of lags in callosal interactions, very comparable to similar estimates of callosal conduction delays derived from neuroanatomical measurements (Caminiti et al., 2013).

No MeSH data available.


Related in: MedlinePlus

Modulation of two LFPs (left panel) and their zCC0 (right panel) during the seven task periods. Although the LFP magnitude increased after the first period, it did not show systematic modulation during the subsequent periods. In contrast, zCC0 was obviously modulated, peaking at period 3, the most cognitively demanding period.
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Figure 5: Modulation of two LFPs (left panel) and their zCC0 (right panel) during the seven task periods. Although the LFP magnitude increased after the first period, it did not show systematic modulation during the subsequent periods. In contrast, zCC0 was obviously modulated, peaking at period 3, the most cognitively demanding period.

Mentions: By task design, the cognitive demand differed among periods, such that it was highest during the sample period (when the test bar had to be categorized as High or Low, Figure 1) and lowest during the initial fixation period and the last two response periods. We found that CC0 was modulated across task periods, being highest in the sample period and much lower at the beginning and the end of the trial. An example from a LFP pair is illustrated in Figure 5. Mean values across all trials and periods are shown in Figures 6, 7 for recordings in the same and opposite hemispheres, respectively. We evaluated the statistical significance of this variation by performing a repeated measures analysis of covariance (ANCOVA) in which the seven periods of the task were the repeated measures factor, the hemisphere (same or across) and repetition were “between-subjects” factors, and the vertical position of the task box on the screen and the elapsed time for recording the trial were covariates. Bonferroni tests in the ANCOVA showed that zCC0 in the sample period differed highly significantly from all others (P < 0.001) both within the same hemisphere and across hemispheres.


Cognitive modulation of local and callosal neural interactions in decision making.

Merchant H, Crowe DA, Fortes AF, Georgopoulos AP - Front Neurosci (2014)

Modulation of two LFPs (left panel) and their zCC0 (right panel) during the seven task periods. Although the LFP magnitude increased after the first period, it did not show systematic modulation during the subsequent periods. In contrast, zCC0 was obviously modulated, peaking at period 3, the most cognitively demanding period.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4128092&req=5

Figure 5: Modulation of two LFPs (left panel) and their zCC0 (right panel) during the seven task periods. Although the LFP magnitude increased after the first period, it did not show systematic modulation during the subsequent periods. In contrast, zCC0 was obviously modulated, peaking at period 3, the most cognitively demanding period.
Mentions: By task design, the cognitive demand differed among periods, such that it was highest during the sample period (when the test bar had to be categorized as High or Low, Figure 1) and lowest during the initial fixation period and the last two response periods. We found that CC0 was modulated across task periods, being highest in the sample period and much lower at the beginning and the end of the trial. An example from a LFP pair is illustrated in Figure 5. Mean values across all trials and periods are shown in Figures 6, 7 for recordings in the same and opposite hemispheres, respectively. We evaluated the statistical significance of this variation by performing a repeated measures analysis of covariance (ANCOVA) in which the seven periods of the task were the repeated measures factor, the hemisphere (same or across) and repetition were “between-subjects” factors, and the vertical position of the task box on the screen and the elapsed time for recording the trial were covariates. Bonferroni tests in the ANCOVA showed that zCC0 in the sample period differed highly significantly from all others (P < 0.001) both within the same hemisphere and across hemispheres.

Bottom Line: They were observed both within area 7a of the posterior parietal cortex and between symmetric 7a areas of the two hemispheres.Time lags for maximum interactions were longer for opposite- vs. same-hemisphere recordings, and lags for negative interactions were longer than for positive interactions in both recording sites.These findings underscore the involvement of dynamic neuronal interactions in cognitive processing within and across hemispheres.

View Article: PubMed Central - PubMed

Affiliation: Department of Behavioral and Cognitive Neurobiology, Instituto de Neurobiología, UNAM Querétaro, México.

ABSTRACT
Traditionally, the neurophysiological mechanisms of cognitive processing have been investigated at the single cell level. Here we show that the dynamic, millisecond-by-millisecond, interactions between neuronal events measured by local field potentials are modulated in an orderly fashion by key task variables of a space categorization task performed by monkeys. These interactions were stronger during periods of higher cognitive load and varied in sign (positive, negative). They were observed both within area 7a of the posterior parietal cortex and between symmetric 7a areas of the two hemispheres. Time lags for maximum interactions were longer for opposite- vs. same-hemisphere recordings, and lags for negative interactions were longer than for positive interactions in both recording sites. These findings underscore the involvement of dynamic neuronal interactions in cognitive processing within and across hemispheres. They also provide accurate estimates of lags in callosal interactions, very comparable to similar estimates of callosal conduction delays derived from neuroanatomical measurements (Caminiti et al., 2013).

No MeSH data available.


Related in: MedlinePlus