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Michael L. Platt - One of the best experts on this subject based on the ideXlab platform.
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neuronal activity in the Posterior Cingulate Cortex signals environmental information and predicts behavioral variability during trapline foraging
The Journal of Neuroscience, 2021Co-Authors: David L Barack, Michael L. PlattAbstract:Animals engage in routine behavior in order to efficiently navigate their environments. This routine behavior may be influenced by the state of the environment, such as the location and size of rewards. The neural circuits tracking environmental information and how that information impacts decisions to deviate from routines remains unexplored. To investigate the representation of environmental information during routine foraging, we recorded the activity of single neurons in Posterior Cingulate Cortex (PCC) in two male monkeys searching through an array of targets in which the location of rewards was unknown. Outside the laboratory, people and animals solve such traveling salesman problems by following routine traplines that connect nearest-neighbor locations. In our task, monkeys also deployed traplining routines, but as the environment became better known, they deviate from them despite the reduction in foraging efficiency. While foraging, PCC neurons tracked environmental information but not reward and predicted variability in the pattern of choices. Together, these findings suggest that PCC may mediate the influence of information on variability in choice behavior. Significance statement Many animals seek information to better guide their decisions and update behavioral routines. In our study, subjects visually searched through a set of targets on every trial to gather two rewards. Greater amounts of information about the distribution of rewards predicted less variability in choice patterns, whereas smaller amounts predicted greater variability. We recorded from the Posterior Cingulate Cortex, an area implicated in the coding of reward and uncertainty, and discovered that these neurons signaled the expected information about the distribution of rewards instead of signaling expected rewards. The activity in these cells also predicted the amount of variability in choice behavior. These findings suggest that the Posterior Cingulate helps direct the search for information in order to augment routines.
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neuronal activity in the Posterior Cingulate Cortex signals environmental information and predicts behavioral variability during routine foraging
bioRxiv, 2018Co-Authors: Michael L. Platt, David L BarackAbstract:Abstract Animals engage in routine behavior in order to efficiently navigate their environments. This routine behavior may be influenced by the state of the environment, such as the location and size of rewards. The neural circuits tracking environmental information and how that information impacts decisions to diverge from routines remains unexplored. To investigate the representation of environmental information during routine foraging, we recorded the activity of single neurons in Posterior Cingulate Cortex (PCC) in monkeys searching through an array of targets in which the location of rewards was unknown. Outside the laboratory, people and animals solve such traveling salesman problems by following routine traplines that connect nearest-neighbor locations. In our task, monkeys also deployed traplining routines, but as the environment became better known, they diverged from them despite the reduction in foraging efficiency. While foraging, PCC neurons tracked environmental information but not reward and predicted variability in the pattern of choices. Together, these findings suggest that PCC mediates the influence of information on variability in choice behavior.
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causal evidence of performance monitoring by neurons in Posterior Cingulate Cortex during learning
Neuron, 2013Co-Authors: Sarah R Heilbronner, Michael L. PlattAbstract:The Posterior Cingulate Cortex (CGp) is a major hub of the default mode network (DMN), a set of cortical areas with high resting activity that declines during task performance. This relationship suggests that DMN activity contributes to mental processes that are antagonistic to performance. Alternatively, DMN may detect conditions under which performance is poor and marshal cognitive resources for improvement. To test this idea, we recorded activity of CGp neurons in monkeys performing a learning task while varying reward size and novelty. We found that CGp neurons responded to errors, and this activity was magnified by small reward and novel stimuli. Inactivating CGp with muscimol impaired new learning when rewards were small but had no effect when rewards were large; inactivation did not affect performance on well-learned associations. Thus, CGp, and by extension the DMN, may support learning, and possibly other cognitive processes, by monitoring performance and motivating exploration.
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decision salience signals in Posterior Cingulate Cortex
Frontiers in Neuroscience, 2011Co-Authors: Sarah R Heilbronner, Benjamin Y Hayden, Michael L. PlattAbstract:Despite its phylogenetic antiquity and clinical importance, the Posterior Cingulate Cortex (CGp) remains an enigmatic nexus of attention, memory, motivation, and decision making. Here we show that CGp neurons track decision salience—the degree to which an option differs from a standard—but not the subjective value of a decision. To do this, we recorded the spiking activity of CGp neurons in monkeys choosing between options varying in reward-related risk, delay to reward, and social outcomes, each of which varied in level of decision salience. Firing rates were higher when monkeys chose the risky option, consistent with their risk-seeking preferences, but were also higher when monkeys chose the delayed and social options, contradicting their preferences. Thus, across decision contexts, neuronal activity was uncorrelated with how much monkeys valued a given option, as inferred from choice. Instead, neuronal activity signaled the deviation of the chosen option from the standard, independently of how it differed. The observed decision salience signals suggest a role for CGp in the flexible allocation of neural resources to motivationally significant information, akin to the role of attention in selective processing of sensory inputs.
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Posterior Cingulate Cortex adapting behavior to a changing world
Trends in Cognitive Sciences, 2011Co-Authors: John M Pearson, Sarah R Heilbronner, David L Barack, Benjamin Y Hayden, Michael L. PlattAbstract:When has the world changed enough to warrant a new approach? The answer depends on current needs, behavioral flexibility and prior knowledge about the environment. Formal approaches solve the problem by integrating the recent history of rewards, errors, uncertainty and context via Bayesian inference to detect changes in the world and alter behavioral policy. Neuronal activity in Posterior Cingulate Cortex – a key node in the default network – is known to vary with learning, memory, reward and task engagement. We propose that these modulations reflect the underlying process of change detection and motivate subsequent shifts in behavior.
Michael H. Buonocore - One of the best experts on this subject based on the ideXlab platform.
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Posterior Cingulate Cortex activation by emotional words fmri evidence from a valence decision task
Human Brain Mapping, 2003Co-Authors: Richard J. Maddock, Amy Garrett, Michael H. BuonocoreAbstract:Functional imaging studies consistently find that emotional stimuli activate the Posterior Cingulate Cortex, a region that appears to have memory-related functions. However, prior imaging studies have not controlled for non-emotional stimulus features that might activate this region by engaging memory processes unrelated to emotion. This study examined whether emotional words activated the Posterior Cingulate Cortex when these potentially confounding factors were controlled. Sixty-four pleasant and 64 unpleasant words were matched with neutral words on non-emotional features known to influence memory. Eight subjects underwent block-designed functional magnetic resonance imaging scans while evaluating the valence of these words. The Posterior Cingulate Cortex was significantly activated bilaterally during both unpleasant and pleasant compared to neutral words. The strongest activation peak with both unpleasant and pleasant words was observed in the left subgenual Cingulate Cortex. Anteromedial orbital and left inferior and middle frontal cortices were also activated by both pleasant and unpleasant words. Right amygdala and auditory Cortex were activated only by unpleasant words, while left frontal pole was activated only by pleasant words. The results show that activation of the Posterior Cingulate Cortex by emotional stimuli cannot be attributed to the memory-enhancing effects of non-emotional stimulus features. The findings are consistent with the suggestion that this region may mediate interactions of emotional and memory-related processes. The results also extend prior findings that evaluating emotional words consistently activates the subgenual Cingulate Cortex, and suggest a means of probing this region in patients with mood disorders.
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Posterior Cingulate Cortex activation by emotional words fmri evidence from a valence decision task
Human Brain Mapping, 2003Co-Authors: Richard J. Maddock, Amy Garrett, Michael H. BuonocoreAbstract:Functional imaging studies consistently find that emotional stimuli activate the Posterior Cingulate Cortex, a region that appears to have memory-related functions. However, prior imaging studies have not controlled for non-emotional stimulus features that might activate this region by engaging memory processes unrelated to emotion. This study examined whether emotional words activated the Posterior Cingulate Cortex when these potentially confounding factors were controlled. Sixty-four pleasant and 64 unpleasant words were matched with neutral words on non-emotional features known to influence memory. Eight subjects underwent block-designed functional magnetic resonance imaging scans while evaluating the valence of these words. The Posterior Cingulate Cortex was significantly activated bilaterally during both unpleasant and pleasant compared to neutral words. The strongest activation peak with both unpleasant and pleasant words was observed in the left subgenual Cingulate Cortex. Anteromedial orbital and left inferior and middle frontal cortices were also activated by both pleasant and unpleasant words. Right amygdala and auditory Cortex were activated only by unpleasant words, while left frontal pole was activated only by pleasant words. The results show that activation of the Posterior Cingulate Cortex by emotional stimuli cannot be attributed to the memory-enhancing effects of non-emotional stimulus features. The findings are consistent with the suggestion that this region may mediate interactions of emotional and memory-related processes. The results also extend prior findings that evaluating emotional words consistently activates the subgenual Cingulate Cortex, and suggest a means of probing this region in patients with mood disorders. Hum. Brain Mapping 18:30 - 41, 2003. © 2002 Wiley-Liss, Inc.
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Remembering familiar people: the Posterior Cingulate Cortex and autobiographical memory retrieval.
Neuroscience, 2001Co-Authors: Richard J. Maddock, Amy Garrett, Michael H. BuonocoreAbstract:Most functional imaging studies of memory retrieval investigate memory for standardized laboratory stimuli. However, naturally acquired autobiographical memories differ from memories of standardized stimuli in important ways. Neuroimaging studies of natural memories may reveal distinctive patterns of brain activation and may have particular value in assessing clinical disorders of memory. This study used functional magnetic resonance imaging to investigate brain activation during successful retrieval of autobiographical memories elicited by name-cued recall of family members and friends. The caudal part of the left Posterior Cingulate Cortex was the most strongly activated region and was significantly activated in all eight subjects studied. Most subjects also showed significant activation of the left anterior orbitomedial, anterior middle frontal, precuneus, cuneus, and Posterior inferior parietal cortices, and the right Posterior Cingulate and motor cortices.Our findings are consistent with prior studies showing Posterior Cingulate Cortex activation during autobiographical memory retrieval. This region is also consistently activated during retrieval of standardized memory stimuli when experimental designs emphasizing successful retrieval are employed. Our results support the hypothesis that the Posterior Cingulate Cortex plays an important role in successful memory retrieval. The Posterior Cingulate Cortex has strong reciprocal connections with entorhinal and parahippocampal cortices. Studies of early Alzheimer's disease, temporal lobectomy, and hypoxic amnesia show that hypometabolism of the Posterior Cingulate Cortex is an early and prominent indicator of pathology in these patients. Our findings suggest that autobiographical memory retrieval tasks could be used to probe the functional status of the Posterior Cingulate Cortex in patients with early Alzheimer's disease or at risk for that condition.
Guillaume Marrelec - One of the best experts on this subject based on the ideXlab platform.
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the precuneus Posterior Cingulate Cortex plays a pivotal role in the default mode network evidence from a partial correlation network analysis
NeuroImage, 2008Co-Authors: Peter Fransson, Guillaume MarrelecAbstract:Abstract Recent research has shown that intrinsic brain activity as observed by functional magnetic resonance imaging (fMRI) manifest itself as coherent signal changes in networks encompassing brain regions that span long-range neuronal pathways. One of these networks, the so called default mode network, has become the primary target in recent investigations to link intrinsic activity to cognition and how intrinsic signal changes may be altered in disease. In this study we assessed functional connectivity within the default mode network during both rest and a continuous working memory task on a region-by-region basis using partial correlation analysis, a data-driven method that provides insight into effective connectivity within neuronal networks. Prominent features of functional connectivity within the default mode network included an overall strong level of interaction between the precuneus/Posterior Cingulate region and the rest of the default mode network, as well as a high degree of interaction between the left and right medial temporal lobes combined with weak interactions between the medial temporal lobes and the rest of the default mode network. Additionally, we found support for strong interactions between the precuneus/Posterior Cingulate Cortex and the left inferior parietal lobe as well as between the dorsal and ventral sections of the medial prefrontal Cortex. The suggested pivotal role of the precuneus/Posterior Cingulate Cortex in the default mode network is discussed.
Richard J. Maddock - One of the best experts on this subject based on the ideXlab platform.
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Posterior Cingulate Cortex activation by emotional words fmri evidence from a valence decision task
Human Brain Mapping, 2003Co-Authors: Richard J. Maddock, Amy Garrett, Michael H. BuonocoreAbstract:Functional imaging studies consistently find that emotional stimuli activate the Posterior Cingulate Cortex, a region that appears to have memory-related functions. However, prior imaging studies have not controlled for non-emotional stimulus features that might activate this region by engaging memory processes unrelated to emotion. This study examined whether emotional words activated the Posterior Cingulate Cortex when these potentially confounding factors were controlled. Sixty-four pleasant and 64 unpleasant words were matched with neutral words on non-emotional features known to influence memory. Eight subjects underwent block-designed functional magnetic resonance imaging scans while evaluating the valence of these words. The Posterior Cingulate Cortex was significantly activated bilaterally during both unpleasant and pleasant compared to neutral words. The strongest activation peak with both unpleasant and pleasant words was observed in the left subgenual Cingulate Cortex. Anteromedial orbital and left inferior and middle frontal cortices were also activated by both pleasant and unpleasant words. Right amygdala and auditory Cortex were activated only by unpleasant words, while left frontal pole was activated only by pleasant words. The results show that activation of the Posterior Cingulate Cortex by emotional stimuli cannot be attributed to the memory-enhancing effects of non-emotional stimulus features. The findings are consistent with the suggestion that this region may mediate interactions of emotional and memory-related processes. The results also extend prior findings that evaluating emotional words consistently activates the subgenual Cingulate Cortex, and suggest a means of probing this region in patients with mood disorders.
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Posterior Cingulate Cortex activation by emotional words fmri evidence from a valence decision task
Human Brain Mapping, 2003Co-Authors: Richard J. Maddock, Amy Garrett, Michael H. BuonocoreAbstract:Functional imaging studies consistently find that emotional stimuli activate the Posterior Cingulate Cortex, a region that appears to have memory-related functions. However, prior imaging studies have not controlled for non-emotional stimulus features that might activate this region by engaging memory processes unrelated to emotion. This study examined whether emotional words activated the Posterior Cingulate Cortex when these potentially confounding factors were controlled. Sixty-four pleasant and 64 unpleasant words were matched with neutral words on non-emotional features known to influence memory. Eight subjects underwent block-designed functional magnetic resonance imaging scans while evaluating the valence of these words. The Posterior Cingulate Cortex was significantly activated bilaterally during both unpleasant and pleasant compared to neutral words. The strongest activation peak with both unpleasant and pleasant words was observed in the left subgenual Cingulate Cortex. Anteromedial orbital and left inferior and middle frontal cortices were also activated by both pleasant and unpleasant words. Right amygdala and auditory Cortex were activated only by unpleasant words, while left frontal pole was activated only by pleasant words. The results show that activation of the Posterior Cingulate Cortex by emotional stimuli cannot be attributed to the memory-enhancing effects of non-emotional stimulus features. The findings are consistent with the suggestion that this region may mediate interactions of emotional and memory-related processes. The results also extend prior findings that evaluating emotional words consistently activates the subgenual Cingulate Cortex, and suggest a means of probing this region in patients with mood disorders. Hum. Brain Mapping 18:30 - 41, 2003. © 2002 Wiley-Liss, Inc.
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Remembering familiar people: the Posterior Cingulate Cortex and autobiographical memory retrieval.
Neuroscience, 2001Co-Authors: Richard J. Maddock, Amy Garrett, Michael H. BuonocoreAbstract:Most functional imaging studies of memory retrieval investigate memory for standardized laboratory stimuli. However, naturally acquired autobiographical memories differ from memories of standardized stimuli in important ways. Neuroimaging studies of natural memories may reveal distinctive patterns of brain activation and may have particular value in assessing clinical disorders of memory. This study used functional magnetic resonance imaging to investigate brain activation during successful retrieval of autobiographical memories elicited by name-cued recall of family members and friends. The caudal part of the left Posterior Cingulate Cortex was the most strongly activated region and was significantly activated in all eight subjects studied. Most subjects also showed significant activation of the left anterior orbitomedial, anterior middle frontal, precuneus, cuneus, and Posterior inferior parietal cortices, and the right Posterior Cingulate and motor cortices.Our findings are consistent with prior studies showing Posterior Cingulate Cortex activation during autobiographical memory retrieval. This region is also consistently activated during retrieval of standardized memory stimuli when experimental designs emphasizing successful retrieval are employed. Our results support the hypothesis that the Posterior Cingulate Cortex plays an important role in successful memory retrieval. The Posterior Cingulate Cortex has strong reciprocal connections with entorhinal and parahippocampal cortices. Studies of early Alzheimer's disease, temporal lobectomy, and hypoxic amnesia show that hypometabolism of the Posterior Cingulate Cortex is an early and prominent indicator of pathology in these patients. Our findings suggest that autobiographical memory retrieval tasks could be used to probe the functional status of the Posterior Cingulate Cortex in patients with early Alzheimer's disease or at risk for that condition.
Sven Vanneste - One of the best experts on this subject based on the ideXlab platform.
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impaired Posterior Cingulate Cortex parahippocampus connectivity is associated with episodic memory retrieval problems in amnestic mild cognitive impairment
European Journal of Neuroscience, 2021Co-Authors: Sven Vanneste, Alison M Luckey, Lauren S Mcleod, Ian H RobertsonAbstract:Episodic memory retention and retrieval decline are the most common impairments observed in amnestic mild cognitive impairment (aMCI) patients who progress to Alzheimer's disease (AD). Clinical electroencephalography research shows that patients with dementia due to AD exhibit a slowing of neural electrical activity in the parietal Cortex. Memory research has further suggested that successful memory performance is associated with changes in a Posterior Cingulate-parahippocampal cortical network together with increased θ-γ oscillatory coupling, where θ oscillations act as carrier waves for γ oscillations, which contain the actual information. However, the neurophysiological link between the memory research and clinical studies investigating aMCI and AD is lacking. In this study, we look at brain activity in aMCI and how it relates to memory performance. We demonstrate decreased γ power in the Posterior Cingulate Cortex and the left and right parahippocampus in aMCI patients in comparison to control participants. This goes together with reduced θ coherence between the Posterior Cingulate Cortex and parahippocampus associated with altered memory performance aMCI patients in comparison to control participants. In addition, comparing patients with aMCI to control participants reveals an effect for θ-γ coupling for the Posterior Cingulate Cortex, and the left and right parahippocampus. Taken together, our results show that parahippocampus and Posterior Cingulate Cortex interact via θ-γ coupling, which is associated with memory recollection and is altered in aMCI patients, offering a potential candidate mechanism for memory decline in aMCI.
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influencing connectivity and cross frequency coupling by real time source localized neurofeedback of the Posterior Cingulate Cortex reduces tinnitus related distress
Neurobiology of Stress, 2016Co-Authors: Sven Vanneste, Kathleen Joos, Jan Ost, Dirk De RidderAbstract:Abstract Background In this study we are using source localized neurofeedback to moderate tinnitus related distress by influencing neural activity of the target region as well as the connectivity within the default network. Hypothesis We hypothesize that up-training alpha and down-training beta and gamma activity in the Posterior Cingulate Cortex has a moderating effect on tinnitus related distress by influencing neural activity of the target region as well as the connectivity within the default network and other functionally connected brain areas. Methods Fifty-eight patients with chronic tinnitus were included in the study. Twenty-three tinnitus patients received neurofeedback training of the Posterior Cingulate Cortex with the aim of up-training alpha and down-training beta and gamma activity, while 17 patients underwent training of the lingual gyrus as a control situation. A second control group consisted of 18 tinnitus patients on a waiting list for future tinnitus treatment. Results This study revealed that neurofeedback training of the Posterior Cingulate Cortex results in a significant decrease of tinnitus related distress. No significant effect on neural activity of the target region could be obtained. However, functional and effectivity connectivity changes were demonstrated between remote brain regions or functional networks as well as by altering cross frequency coupling of the Posterior Cingulate Cortex. Conclusion This suggests that neurofeedback could remove the information, processed in beta and gamma, from the carrier wave, alpha, which transports the high frequency information and influences the salience attributed to the tinnitus sound. Based on the observation that much pathology is the result of an abnormal functional connectivity within and between neural networks various pathologies should be considered eligible candidates for the application of source localized EEG based neurofeedback training.