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Deviance detection by a P3-like response in rat posterior parietal cortex.

Imada A, Morris A, Wiest MC - Front Integr Neurosci (2013)

Bottom Line: Extending previous results from surface recordings we found, after controlling for the frequencies of the standard and oddball tones, that rat frontal and parietal-evoked LFPs (eLFPs) exhibit significantly larger N1 (~40 ms latency), P2 (~100 ms), N2 (~160 ms), P3E (~200-240 ms), and P3L (~300-500 ms) amplitudes after an oddball tone.We compared the difference between rare-tone and frequent-tone response amplitudes in the two-tone context (oddball effect) or single-tone context which isolates the contribution of SSA (SSA effect).An analysis of variance (ANOVA) revealed a significant main effect of tone context on rare-tone response enhancements, showing that the rare-tone enhancements were stronger in the two-tone context than the single-tone context.

View Article: PubMed Central - PubMed

Affiliation: Neuroscience Program, Wellesley College Wellesley, MA, USA.

ABSTRACT
To better understand sensory processing in frontal and parietal cortex of the rat, and to further assess the rat as a model of human frontal-parietal processing, we recorded local field potentials (LFPs) from microelectrode arrays implanted in medio-dorsal frontal, and posterior parietal cortex of awake rats as they were presented with a succession of frequent "standard" tones and infrequent "oddball" tones. Extending previous results from surface recordings we found, after controlling for the frequencies of the standard and oddball tones, that rat frontal and parietal-evoked LFPs (eLFPs) exhibit significantly larger N1 (~40 ms latency), P2 (~100 ms), N2 (~160 ms), P3E (~200-240 ms), and P3L (~300-500 ms) amplitudes after an oddball tone. These neural oddball effects could contribute to the automatic allocation of attention to rare stimuli. To determine whether these enhanced responses to rare stimuli could be accounted for in terms of stimulus-specific neural adaptation (SSA), we also recorded during single-tone control sessions involving frequent standard, or infrequent oddball beeps alone. We compared the difference between rare-tone and frequent-tone response amplitudes in the two-tone context (oddball effect) or single-tone context which isolates the contribution of SSA (SSA effect). An analysis of variance (ANOVA) revealed a significant main effect of tone context on rare-tone response enhancements, showing that the rare-tone enhancements were stronger in the two-tone context than the single-tone context. This difference between tone contexts was greatest at the early P3E peak (200-240 ms post-beep) in parietal cortex, suggesting true deviance detection by this evoked response component, which cannot be accounted for in terms of simple models of SSA.

No MeSH data available.


Grand average eLFPs for the two-tone oddball paradigm. (A,B) eLFPs averaged over session-pairs recorded in14 rats, from frontal (A) and parietal (B) cortex, for oddball tones (red) and standard tones (blue) separately. (C,D) plot the grand average difference between the oddball and standard eLFPs at frontal (C) and parietal (D) electrodes, with the shaded region representing a 68% confidence interval based on the variability across sessions. In both brain regions, evoked responses tend to be larger in amplitude when the tone is presented as a rare oddball, as opposed to when the same tone is presented as a frequent standard.
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Figure 2: Grand average eLFPs for the two-tone oddball paradigm. (A,B) eLFPs averaged over session-pairs recorded in14 rats, from frontal (A) and parietal (B) cortex, for oddball tones (red) and standard tones (blue) separately. (C,D) plot the grand average difference between the oddball and standard eLFPs at frontal (C) and parietal (D) electrodes, with the shaded region representing a 68% confidence interval based on the variability across sessions. In both brain regions, evoked responses tend to be larger in amplitude when the tone is presented as a rare oddball, as opposed to when the same tone is presented as a frequent standard.

Mentions: Our first approach to the question of whether the N1, P2, N2, P3E, and P3L peaks manifest larger amplitudes in response to rare oddballs in a background of frequent standards was by means of grand average differences between oddball and standard eLFPs (Figure 2). The trend in both frontal and parietal cortex is toward larger amplitude peaks in response to the tone presented as rare oddball, at each of the components we focused on. However, Figure 2 also suggests the possibility that peaks may be shifted with respect to one another in the oddball and standard eLFPs. For example, the positive peaks after 150 ms appear at different latencies in the oddball and standard eLFPs (Figures 2A,B). Thus, the raw difference between oddball and standard eLFPs may not be the most appropriate way to assess a putative enhancement of a given peak. Moreover, because eLFP peaks appear at different latencies in different animals, and even in different sessions recorded from the same animal, significant effects could be obscured in the grand average eLFP difference curves.


Deviance detection by a P3-like response in rat posterior parietal cortex.

Imada A, Morris A, Wiest MC - Front Integr Neurosci (2013)

Grand average eLFPs for the two-tone oddball paradigm. (A,B) eLFPs averaged over session-pairs recorded in14 rats, from frontal (A) and parietal (B) cortex, for oddball tones (red) and standard tones (blue) separately. (C,D) plot the grand average difference between the oddball and standard eLFPs at frontal (C) and parietal (D) electrodes, with the shaded region representing a 68% confidence interval based on the variability across sessions. In both brain regions, evoked responses tend to be larger in amplitude when the tone is presented as a rare oddball, as opposed to when the same tone is presented as a frequent standard.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3539781&req=5

Figure 2: Grand average eLFPs for the two-tone oddball paradigm. (A,B) eLFPs averaged over session-pairs recorded in14 rats, from frontal (A) and parietal (B) cortex, for oddball tones (red) and standard tones (blue) separately. (C,D) plot the grand average difference between the oddball and standard eLFPs at frontal (C) and parietal (D) electrodes, with the shaded region representing a 68% confidence interval based on the variability across sessions. In both brain regions, evoked responses tend to be larger in amplitude when the tone is presented as a rare oddball, as opposed to when the same tone is presented as a frequent standard.
Mentions: Our first approach to the question of whether the N1, P2, N2, P3E, and P3L peaks manifest larger amplitudes in response to rare oddballs in a background of frequent standards was by means of grand average differences between oddball and standard eLFPs (Figure 2). The trend in both frontal and parietal cortex is toward larger amplitude peaks in response to the tone presented as rare oddball, at each of the components we focused on. However, Figure 2 also suggests the possibility that peaks may be shifted with respect to one another in the oddball and standard eLFPs. For example, the positive peaks after 150 ms appear at different latencies in the oddball and standard eLFPs (Figures 2A,B). Thus, the raw difference between oddball and standard eLFPs may not be the most appropriate way to assess a putative enhancement of a given peak. Moreover, because eLFP peaks appear at different latencies in different animals, and even in different sessions recorded from the same animal, significant effects could be obscured in the grand average eLFP difference curves.

Bottom Line: Extending previous results from surface recordings we found, after controlling for the frequencies of the standard and oddball tones, that rat frontal and parietal-evoked LFPs (eLFPs) exhibit significantly larger N1 (~40 ms latency), P2 (~100 ms), N2 (~160 ms), P3E (~200-240 ms), and P3L (~300-500 ms) amplitudes after an oddball tone.We compared the difference between rare-tone and frequent-tone response amplitudes in the two-tone context (oddball effect) or single-tone context which isolates the contribution of SSA (SSA effect).An analysis of variance (ANOVA) revealed a significant main effect of tone context on rare-tone response enhancements, showing that the rare-tone enhancements were stronger in the two-tone context than the single-tone context.

View Article: PubMed Central - PubMed

Affiliation: Neuroscience Program, Wellesley College Wellesley, MA, USA.

ABSTRACT
To better understand sensory processing in frontal and parietal cortex of the rat, and to further assess the rat as a model of human frontal-parietal processing, we recorded local field potentials (LFPs) from microelectrode arrays implanted in medio-dorsal frontal, and posterior parietal cortex of awake rats as they were presented with a succession of frequent "standard" tones and infrequent "oddball" tones. Extending previous results from surface recordings we found, after controlling for the frequencies of the standard and oddball tones, that rat frontal and parietal-evoked LFPs (eLFPs) exhibit significantly larger N1 (~40 ms latency), P2 (~100 ms), N2 (~160 ms), P3E (~200-240 ms), and P3L (~300-500 ms) amplitudes after an oddball tone. These neural oddball effects could contribute to the automatic allocation of attention to rare stimuli. To determine whether these enhanced responses to rare stimuli could be accounted for in terms of stimulus-specific neural adaptation (SSA), we also recorded during single-tone control sessions involving frequent standard, or infrequent oddball beeps alone. We compared the difference between rare-tone and frequent-tone response amplitudes in the two-tone context (oddball effect) or single-tone context which isolates the contribution of SSA (SSA effect). An analysis of variance (ANOVA) revealed a significant main effect of tone context on rare-tone response enhancements, showing that the rare-tone enhancements were stronger in the two-tone context than the single-tone context. This difference between tone contexts was greatest at the early P3E peak (200-240 ms post-beep) in parietal cortex, suggesting true deviance detection by this evoked response component, which cannot be accounted for in terms of simple models of SSA.

No MeSH data available.