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Inhibition load changes the brain activation irrespective of attentional differences: A functional magnetic resonance imaging study
Abstracts / Neuroscience Research 71S (2011) e108–e415
P4-o11 Neuronal correlates of cognitive resource allocation revealed by a dual-task paradigm Kei Watanabe , Shintaro Funahashi Kokoro Res. Center, Kyoto Univ., Kyoto The need to perform two tasks concurrently (e.g., talking while driving) is common in everyday life. Dual-tasking often results in a detriment of both or one of the component tasks. This well-known phenomenon, dual-task interference, is thought of as a sign of widely held psychological constructs, the capacity-limited cognitive resource and as-needed allocation of it. However, physiological underpinnings of these notions have rarely been tested on the single neuronal level. In the present, in order to characterize the neuronal basis of cognitive resource and its allocation, we recorded and analyzed lateral prefrontal neuron activities while the monkeys performed a dual-task, involving two concurrently performed component tasks using two effectors (hand and eye), a cue-attention (CA) and a memory-guided saccade (MGS) tasks. Our primary focus was on whether and how task-related activities observed in singly performed MGS task were modulated when the task was concurrently performed with CA task. The dual-task interference was evident on both the behavioral and neural level. There was a significant reduction in the magnitude and the selectivity among MGS task-related activities in the dual-task context. The degree of the attenuation was correlated with the behavioral demand of the concurrently performed CA task. The results suggest that (1) the PFC neurons’ ability to process behaviorally relevant information is subject to the capacity limit, (2) the limited encoding capacity is allocated among concurrently performed tasks on as-needed basis. Research fund: KAKENHI (21240024). doi:10.1016/j.neures.2011.07.1672
P4-o12 Multidimensional representations of task phases in the lateral prefrontal cortex Yosuke Saga 1,2 , Michiyo Iba 1 , Jun Tanji 1,3 , Eiji Hoshi 1,2 1 3
Tamagawa Univ., Brain Sci. Inst Tohoku Univ., Brain Sci. Center
2
Tokyo Metropolitan Inst., Medical Sci
The temporal structuring of multiple events is essential for the purposeful regulation of behavior. We investigated the role of the lateral prefrontal cortex (LPFC) in transforming external signals of multiple sensory modalities into information suitable for monitoring successive events across behavioral phases. We trained monkeys (Macaca fuscata) to receive a succession of 1s visual, auditory, or tactile sensory signals separated by variable intervals and then to release a key as soon as the fourth signal appeared. We used a square (10◦ × 10◦ ) as a visual stimulus, a 500 Hz pure tone as an auditory stimulus, and 20 Hz sinusoidal vibrations as a tactile stimulus. In each trial, sensory stimuli of only one modality were delivered. After a block of 5 trials, the sensory modality was switched. To perform this task successfully, it was necessary to detect the appearance of each sensory stimulus and to keep track of the phase of the behavioral task updated by the appearance of the sensory signal. We subsequently recorded neuronal activity from LPFC while the monkeys performed the task. We found that the initial, shortlatency responses of LPFC neurons reflected primarily the sensory modality, rather than the phase or progress of the task. However, a task-phase-selective response developed within 500 ms of signal reception, and information about the task phase was maintained throughout the presentation of successive cues. The task-phase selective activity was updated with the appearance of each cue until the planned action was initiated. The phase-selective activity of individual neurons reflected not only merely a particular phase of the task but also multiple successive phases. Furthermore, we found combined representations of task phase and sensory modality in the activity of individual LPFC neurons. These properties suggest how information representing multiple phases of behavioral events develops in the LPFC to provide a basis for the temporal regulation of behavior. Research fund: KAKENHI (19300110) KAKENHI (19670004) Takeda Science Foundation. doi:10.1016/j.neures.2011.07.1673
e381
P4-o13 Inhibition load changes the brain activation irrespective of attentional differences: A functional magnetic resonance imaging study Hisakazu Yanaka 1,2 , Daisuke N. Saito 1,2 , Takanori Kochiyama 5 , Takeshi Fujii 2 , Hirotaka Kosaka 2,3 , Taisuke Shimada 2,4 , Tatsuya Asai 2,4 , Hidehiko Okazawa 1,2 1 Research and Education Program for Life Science, University of Fukui, Fukui, Japan 2 Biomedical Imaging Research Center, University of Fukui, Fukui, Japan 3 Department of Neuropsychiatry, Faculty of Medical Sciences, University of Fukui, Fukui, Japan 4 Faculty of Engineering, University of Fukui, Fukui, Japan 5 Brain Activity Imaging Center, ATR-Promotions, Advanced Telecommunications Research Institute, Kyoto, Japan
Response inhibition is defined as the ability to inhibit the inappropriate motor response due to the prominent response tendency. Previous neuroimaging studies have suggested that the lateral prefrontal cortex (PFC) is related to the response inhibition using Go/NoGo task. However, other regions such as medial frontal cortex including anterior cingulate cortex (ACC) and pre-supplementary motor area (pre-SMA), temporal and parietal region have also been reported. All studies are consistent with the findings that have shown the activation in the frontal region, however, the localization of the activation within and outside of the frontal regions has been variable. To examine whether the response inhibition load affects the variability of brain activation, we conducted a rapid event-related functional magnetic resonance imaging (fMRI) during the different version of three Go/NoGo tasks. Twenty-two healthy right-handed subjects were participated in this study. To induce different inhibition load, we used three tasks which were constituted as follows: High-Go/NoGo-ratio task (Htask), Middle-Go/NoGo-ratio task (Mtask) and Low-Go/NoGo-ratio task (Ltask). We found the activation which was associated with response inhibition through all types of tasks in right posterior dorsolateral PFC (dlPFC), ventrolateral PFC (vlPFC) and medial frontal region. The task-dependent activations were also found in the parietal regions, temporal regions, pre-SMA and ACC. Furthermore, we also found the activation which was dependent on the false alarm rates in the right anterior dlPFC. Thus, the present study demonstrates that the response inhibition load can induce the variability of the brain activation. Research fund: FUKUI BRAIN PROJECT and Research Grant, Research and Education Program for Life Science, University of Fukui. doi:10.1016/j.neures.2011.07.1674
P4-o14 Error-predicting neuronal activities recorded from the anterior cingulate sulcus during performance of Wisconsin Card Sorting Test analog Masaru Kuwabara 1,2 , Farshad A. Mansouri 1 , Keiji Tanaka 1 1
RIKEN-BSI 2 Graduate School of Frontier Biosciences, Osaka University
The anterior cingulate cortex (ACC) is generally active when human subjects perform difficult tasks, and various functions have been proposed for ACC. However, not many of them have been supported by single-cell recording and lesion results in monkeys. Our previous lesion study showed that ACC is essential for the response slowing in error trials in a Wisconsin Card Sorting Test (WCST) analog: responses were slower in error trials than those in correct trials whereas the difference disappeared by a bilateral lesion of ACC (Buckley et al., 2009). To reveal the neuronal basis of this function, we have recorded neuronal activities from the dorsal bank of the anterior cingulate sulcus in intact monkeys performing the same task. When we analyzed the activities in the parts of trials before the feedback was provided, more than a quarter of cells showed significant differences in firing rate between correct and error trials. More cells showed higher activities in error trials. This difference was not due to the more frequent occurrence of errors immediately after rule switches, because only a small part of the cells showed significant interaction between the factors of early/late phase (within block) and correct/error. We also observed such differential activity in the dorsolateral prefrontal cortex (Mansouri et al., 2006), but such activity was less popular there than in ACC. Moreover, about a quater of ACC cells that showed activities significantly correlated with the monkey’s reaction time, for a majority of them in the direction in which the firing rate was higher in slower trials. These results suggest that ACC neuronal circuits are involved in the detection of error likelihood and slowing the response to adjust the network status in real time.
P4-o11 Neuronal correlates of cognitive resource allocation revealed by a dual-task paradigm Kei Watanabe , Shintaro Funahashi Kokoro Res. Center, Kyoto Univ., Kyoto The need to perform two tasks concurrently (e.g., talking while driving) is common in everyday life. Dual-tasking often results in a detriment of both or one of the component tasks. This well-known phenomenon, dual-task interference, is thought of as a sign of widely held psychological constructs, the capacity-limited cognitive resource and as-needed allocation of it. However, physiological underpinnings of these notions have rarely been tested on the single neuronal level. In the present, in order to characterize the neuronal basis of cognitive resource and its allocation, we recorded and analyzed lateral prefrontal neuron activities while the monkeys performed a dual-task, involving two concurrently performed component tasks using two effectors (hand and eye), a cue-attention (CA) and a memory-guided saccade (MGS) tasks. Our primary focus was on whether and how task-related activities observed in singly performed MGS task were modulated when the task was concurrently performed with CA task. The dual-task interference was evident on both the behavioral and neural level. There was a significant reduction in the magnitude and the selectivity among MGS task-related activities in the dual-task context. The degree of the attenuation was correlated with the behavioral demand of the concurrently performed CA task. The results suggest that (1) the PFC neurons’ ability to process behaviorally relevant information is subject to the capacity limit, (2) the limited encoding capacity is allocated among concurrently performed tasks on as-needed basis. Research fund: KAKENHI (21240024). doi:10.1016/j.neures.2011.07.1672
P4-o12 Multidimensional representations of task phases in the lateral prefrontal cortex Yosuke Saga 1,2 , Michiyo Iba 1 , Jun Tanji 1,3 , Eiji Hoshi 1,2 1 3
Tamagawa Univ., Brain Sci. Inst Tohoku Univ., Brain Sci. Center
2
Tokyo Metropolitan Inst., Medical Sci
The temporal structuring of multiple events is essential for the purposeful regulation of behavior. We investigated the role of the lateral prefrontal cortex (LPFC) in transforming external signals of multiple sensory modalities into information suitable for monitoring successive events across behavioral phases. We trained monkeys (Macaca fuscata) to receive a succession of 1s visual, auditory, or tactile sensory signals separated by variable intervals and then to release a key as soon as the fourth signal appeared. We used a square (10◦ × 10◦ ) as a visual stimulus, a 500 Hz pure tone as an auditory stimulus, and 20 Hz sinusoidal vibrations as a tactile stimulus. In each trial, sensory stimuli of only one modality were delivered. After a block of 5 trials, the sensory modality was switched. To perform this task successfully, it was necessary to detect the appearance of each sensory stimulus and to keep track of the phase of the behavioral task updated by the appearance of the sensory signal. We subsequently recorded neuronal activity from LPFC while the monkeys performed the task. We found that the initial, shortlatency responses of LPFC neurons reflected primarily the sensory modality, rather than the phase or progress of the task. However, a task-phase-selective response developed within 500 ms of signal reception, and information about the task phase was maintained throughout the presentation of successive cues. The task-phase selective activity was updated with the appearance of each cue until the planned action was initiated. The phase-selective activity of individual neurons reflected not only merely a particular phase of the task but also multiple successive phases. Furthermore, we found combined representations of task phase and sensory modality in the activity of individual LPFC neurons. These properties suggest how information representing multiple phases of behavioral events develops in the LPFC to provide a basis for the temporal regulation of behavior. Research fund: KAKENHI (19300110) KAKENHI (19670004) Takeda Science Foundation. doi:10.1016/j.neures.2011.07.1673
e381
P4-o13 Inhibition load changes the brain activation irrespective of attentional differences: A functional magnetic resonance imaging study Hisakazu Yanaka 1,2 , Daisuke N. Saito 1,2 , Takanori Kochiyama 5 , Takeshi Fujii 2 , Hirotaka Kosaka 2,3 , Taisuke Shimada 2,4 , Tatsuya Asai 2,4 , Hidehiko Okazawa 1,2 1 Research and Education Program for Life Science, University of Fukui, Fukui, Japan 2 Biomedical Imaging Research Center, University of Fukui, Fukui, Japan 3 Department of Neuropsychiatry, Faculty of Medical Sciences, University of Fukui, Fukui, Japan 4 Faculty of Engineering, University of Fukui, Fukui, Japan 5 Brain Activity Imaging Center, ATR-Promotions, Advanced Telecommunications Research Institute, Kyoto, Japan
Response inhibition is defined as the ability to inhibit the inappropriate motor response due to the prominent response tendency. Previous neuroimaging studies have suggested that the lateral prefrontal cortex (PFC) is related to the response inhibition using Go/NoGo task. However, other regions such as medial frontal cortex including anterior cingulate cortex (ACC) and pre-supplementary motor area (pre-SMA), temporal and parietal region have also been reported. All studies are consistent with the findings that have shown the activation in the frontal region, however, the localization of the activation within and outside of the frontal regions has been variable. To examine whether the response inhibition load affects the variability of brain activation, we conducted a rapid event-related functional magnetic resonance imaging (fMRI) during the different version of three Go/NoGo tasks. Twenty-two healthy right-handed subjects were participated in this study. To induce different inhibition load, we used three tasks which were constituted as follows: High-Go/NoGo-ratio task (Htask), Middle-Go/NoGo-ratio task (Mtask) and Low-Go/NoGo-ratio task (Ltask). We found the activation which was associated with response inhibition through all types of tasks in right posterior dorsolateral PFC (dlPFC), ventrolateral PFC (vlPFC) and medial frontal region. The task-dependent activations were also found in the parietal regions, temporal regions, pre-SMA and ACC. Furthermore, we also found the activation which was dependent on the false alarm rates in the right anterior dlPFC. Thus, the present study demonstrates that the response inhibition load can induce the variability of the brain activation. Research fund: FUKUI BRAIN PROJECT and Research Grant, Research and Education Program for Life Science, University of Fukui. doi:10.1016/j.neures.2011.07.1674
P4-o14 Error-predicting neuronal activities recorded from the anterior cingulate sulcus during performance of Wisconsin Card Sorting Test analog Masaru Kuwabara 1,2 , Farshad A. Mansouri 1 , Keiji Tanaka 1 1
RIKEN-BSI 2 Graduate School of Frontier Biosciences, Osaka University
The anterior cingulate cortex (ACC) is generally active when human subjects perform difficult tasks, and various functions have been proposed for ACC. However, not many of them have been supported by single-cell recording and lesion results in monkeys. Our previous lesion study showed that ACC is essential for the response slowing in error trials in a Wisconsin Card Sorting Test (WCST) analog: responses were slower in error trials than those in correct trials whereas the difference disappeared by a bilateral lesion of ACC (Buckley et al., 2009). To reveal the neuronal basis of this function, we have recorded neuronal activities from the dorsal bank of the anterior cingulate sulcus in intact monkeys performing the same task. When we analyzed the activities in the parts of trials before the feedback was provided, more than a quarter of cells showed significant differences in firing rate between correct and error trials. More cells showed higher activities in error trials. This difference was not due to the more frequent occurrence of errors immediately after rule switches, because only a small part of the cells showed significant interaction between the factors of early/late phase (within block) and correct/error. We also observed such differential activity in the dorsolateral prefrontal cortex (Mansouri et al., 2006), but such activity was less popular there than in ACC. Moreover, about a quater of ACC cells that showed activities significantly correlated with the monkey’s reaction time, for a majority of them in the direction in which the firing rate was higher in slower trials. These results suggest that ACC neuronal circuits are involved in the detection of error likelihood and slowing the response to adjust the network status in real time.