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Comparison of the neural activity between the task and passive tone condition. A, An example of the firing patterns from sound-evoked cells, which demonstrated firing increases during stimulus onset. The data from 0.5 s before to 1 s after stimulus onset are shown. Top panels, Raster plots for each tone condition. Yellow lines indicate the stimulus tone onset times. Middle panels, PSTHs of the high-tone trials (red) and low-tone trials (green). Dashed lines indicate the stimulus onset times. Bottom panels, auROC values of the task conditions for defining sound-evoked cells. The color scale represents the auROC values. Nonsignificant auROC values close to 0 are expressed in black. B, Comparison of the proportion of sound-evoked cells between the task and passive tone condition. C, Comparison of the proportion of frequency-selective cells between the task and passive tone condition. D, Comparison of the selectivity of frequency-selective cells between the task and passive tone condition. ***p , 0.01; *p,0.05; n.s.; not significant.
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The activity of primary auditory cortex (A1) neurons is modulated not only by sensory inputs but also by other task-related variables in associative learning. However, it is unclear how A1 neural activity changes dynamically in response to these variables during the learning process of associative memory tasks. Therefore, we developed an associativ...
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... auROC values of all conditions were calculated by comparing the firing rates of each period to the baseline of each condition that were significant for five bins in a row from the start of the trial up to 1 s after the response (Fig. ...
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... and the passive tone condition (32 cells) in three of six rats. The tetrodes were not moved, and the recorded cells were from the same cell populations as those used in the task training. In the passive tone condition, 25% (8 of 32) of the neurons showed sound-evoked firing that was modulated by tone presentation, regardless of the tone frequency (Fig. 3A). This type of frequency-insensitive firing was not observed in the associative memory task (Fig. 3B). Moreover, 44% (12 of 27) and 19% (6 of 32) of the neurons were frequency-selective cells (e.g., Fig. 2) in the task and passive tone conditions, respectively. The proportion of frequency-selective cells was significantly higher in the ...
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... recorded cells were from the same cell populations as those used in the task training. In the passive tone condition, 25% (8 of 32) of the neurons showed sound-evoked firing that was modulated by tone presentation, regardless of the tone frequency (Fig. 3A). This type of frequency-insensitive firing was not observed in the associative memory task (Fig. 3B). Moreover, 44% (12 of 27) and 19% (6 of 32) of the neurons were frequency-selective cells (e.g., Fig. 2) in the task and passive tone conditions, respectively. The proportion of frequency-selective cells was significantly higher in the task than in the passive tone condition ( Fig. 3C; Fisher's exact test, p = 4.75 Â 10 À2 ). ...
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... firing was not observed in the associative memory task (Fig. 3B). Moreover, 44% (12 of 27) and 19% (6 of 32) of the neurons were frequency-selective cells (e.g., Fig. 2) in the task and passive tone conditions, respectively. The proportion of frequency-selective cells was significantly higher in the task than in the passive tone condition ( Fig. 3C; Fisher's exact test, p = 4.75 Â 10 À2 ). Furthermore, the frequency selectivity of the frequency-selective cells was higher in the task than in the passive tone condition ( Fig. 3D; Wilcoxon rank-sum test, p = 7.54 Â 10 À4 ...
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... task and passive tone conditions, respectively. The proportion of frequency-selective cells was significantly higher in the task than in the passive tone condition ( Fig. 3C; Fisher's exact test, p = 4.75 Â 10 À2 ). Furthermore, the frequency selectivity of the frequency-selective cells was higher in the task than in the passive tone condition ( Fig. 3D; Wilcoxon rank-sum test, p = 7.54 Â 10 À4 ...
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... of proportions might be related to plastic changes in the tonotopic map related to the learning task, as the tetrodes were not moved throughout the successive days of training and the recording sites were not changed. The proportion of frequency-selective cells was also significantly different between the task and passive tone conditions (Fig. 3C), and the strength of the selectivity was significantly higher in the former than in the latter (Fig. 3D). Furthermore, some frequency-selective cells showed phasic modulation in brief periods following tone presentation, whereas others showed tonic modulation during tone presentation. These results suggest that the frequency ...
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... task, as the tetrodes were not moved throughout the successive days of training and the recording sites were not changed. The proportion of frequency-selective cells was also significantly different between the task and passive tone conditions (Fig. 3C), and the strength of the selectivity was significantly higher in the former than in the latter (Fig. 3D). Furthermore, some frequency-selective cells showed phasic modulation in brief periods following tone presentation, whereas others showed tonic modulation during tone presentation. These results suggest that the frequency selectivity of A1 neurons emerges strongly when the tone is engaged in a task with choices and rewards. Some ...
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