1
|
Default Mode Network, Meditation, and Age-Associated Brain Changes: What Can We Learn from the Impact of Mental Training on Well-Being as a Psychotherapeutic Approach? Neural Plast 2019; 2019:7067592. [PMID: 31065259 PMCID: PMC6466873 DOI: 10.1155/2019/7067592] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 01/08/2019] [Accepted: 02/26/2019] [Indexed: 12/27/2022] Open
Abstract
Aging is a physiological process accompanied by cognitive decline, principally in memory and executive functions. Alterations in the connectivity of the default mode network (DMN) have been found to participate in cognitive decline, as well as in several neurocognitive disorders. The DMN has antisynchronic activity with attentional networks (task-positive networks (TPN)), which are critical to executive function and memory. Findings pointing to the regulation of the DMN via activation of TPN suggest that it can be used as a strategy for neuroprotection. Meditation is a noninvasive and nonpharmacological technique proven to increase meta-awareness, a cognitive ability which involves the control of both networks. In this review, we discuss the possibility of facilitating healthy aging through the regulation of networks through meditation. We propose that by practicing specific types of meditation, cognitive decline could be slowed, promoting a healthy lifestyle, which may enhance the quality of life for the elderly.
Collapse
|
2
|
Møller A, Rømer Thomsen K, Brooks DJ, Mouridsen K, Blicher JU, Hansen KV, Lou HC. Attenuation of dopamine-induced GABA release in problem gamblers. Brain Behav 2019; 9:e01239. [PMID: 30788911 PMCID: PMC6422713 DOI: 10.1002/brb3.1239] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 01/17/2019] [Accepted: 01/18/2019] [Indexed: 12/17/2022] Open
Abstract
INTRODUCTION We have previously shown that an interaction between medial prefrontal and parietal cortices is instrumental in promoting self-awareness via synchronizing oscillations in the gamma range. The synchronization of these oscillations is modulated by dopamine release. Given that such oscillations result from intermittent GABA stimulation of pyramidal cells, it is of interest to determine whether the dopaminergic system regulates GABA release directly in cortical paralimbic regions. Here, we test the hypothesis that the regulation of the GABA-ergic system by the dopaminergic system becomes attenuated in problem gamblers resulting in addictive behaviors and impaired self-awareness. METHODS [11 C]Ro15-4513 PET, a marker of benzodiazepine α1/α5 receptor availability in the GABA receptor complex, was used to detect changes in synaptic GABA levels after oral doses of 100mg L-dopa in a double-blind controlled study of male problem gamblers (N = 10) and age-matched healthy male controls (N = 10). RESULTS The mean reduction of cortical gray matter GABA/BDZ receptor availability induced by L-dopa was significantly attenuated in the problem gambling group compared to the healthy control group (p = 0.0377). CONCLUSIONS Our findings demonstrate that: (a) Exogenous dopamine can induce synaptic GABA release in healthy controls. (b) This release is attenuated in frontal cortical areas of males suffering from problem gambling, possibly contributing to their loss of inhibitory control. This suggests that dysfunctional dopamine regulation of GABA release may contribute to problem gambling and gambling disorder.
Collapse
Affiliation(s)
- Arne Møller
- Nuclear Medicine and PET-Center, Aarhus University Hospital, Aarhus, Denmark.,Center of Functionally Integrative Neuroscience, Aarhus University, Aarhus, Denmark
| | | | - David J Brooks
- Nuclear Medicine and PET-Center, Aarhus University Hospital, Aarhus, Denmark.,Center of Functionally Integrative Neuroscience, Aarhus University, Aarhus, Denmark.,Division of Neuroscience, University of Newcastle, Tyne, UK
| | - Kim Mouridsen
- Center of Functionally Integrative Neuroscience, Aarhus University, Aarhus, Denmark
| | - Jakob U Blicher
- Center of Functionally Integrative Neuroscience, Aarhus University, Aarhus, Denmark
| | - Kim V Hansen
- Nuclear Medicine and PET-Center, Aarhus University Hospital, Aarhus, Denmark
| | - Hans C Lou
- Center of Functionally Integrative Neuroscience, Aarhus University, Aarhus, Denmark
| |
Collapse
|
3
|
Pillay S, Liu X, Baracskay P, Hudetz AG. Brainstem stimulation increases functional connectivity of basal forebrain-paralimbic network in isoflurane-anesthetized rats. Brain Connect 2015; 4:523-34. [PMID: 25090190 DOI: 10.1089/brain.2014.0254] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Brain states and cognitive-behavioral functions are precisely controlled by subcortical neuromodulatory networks. Manipulating key components of the ascending arousal system (AAS), via deep-brain stimulation, may help facilitate global arousal in anesthetized animals. Here we test the hypothesis that electrical stimulation of the oral part of the pontine reticular nucleus (PnO) under light isoflurane anesthesia, associated with loss of consciousness, leads to cortical desynchronization and specific changes in blood-oxygenation-level-dependent (BOLD) functional connectivity (FC) of the brain. BOLD signals were acquired simultaneously with frontal epidural electroencephalogram before and after PnO stimulation. Whole-brain FC was mapped using correlation analysis with seeds in major centers of the AAS. PnO stimulation produced cortical desynchronization, a decrease in δ- and θ-band power, and an increase in approximate entropy. Significant increases in FC after PnO stimulation occurred between the left nucleus Basalis of Meynert (NBM) as seed and numerous regions of the paralimbic network. Smaller increases in FC were present between the central medial thalamic nucleus and retrosplenium seeds and the left caudate putamen and NBM. The results suggest that, during light anesthesia, PnO stimulation preferentially modulates basal forebrain-paralimbic networks. We speculate that this may be a reflection of disconnected awareness.
Collapse
Affiliation(s)
- Siveshigan Pillay
- 1 Department of Anesthesiology, Medical College of Wisconsin , Milwaukee, Wisconsin
| | | | | | | |
Collapse
|
4
|
Kringelbach ML. The pleasure of food: underlying brain mechanisms of eating and other pleasures. ACTA ACUST UNITED AC 2015. [DOI: 10.1186/s13411-014-0029-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
|
5
|
Joensson M, Thomsen KR, Andersen LM, Gross J, Mouridsen K, Sandberg K, Østergaard L, Lou HC. Making sense: Dopamine activates conscious self-monitoring through medial prefrontal cortex. Hum Brain Mapp 2015; 36:1866-77. [PMID: 25627861 PMCID: PMC4737196 DOI: 10.1002/hbm.22742] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 01/12/2015] [Indexed: 11/06/2022] Open
Abstract
When experiences become meaningful to the self, they are linked to synchronous activity in a paralimbic network of self-awareness and dopaminergic activity. This network includes medial prefrontal and medial parietal/posterior cingulate cortices, where transcranial magnetic stimulation may transiently impair self-awareness. Conversely, we hypothesize that dopaminergic stimulation may improve self-awareness and metacognition (i.e., the ability of the brain to consciously monitor its own cognitive processes). Here, we demonstrate improved noetic (conscious) metacognition by oral administration of 100 mg dopamine in minimal self-awareness. In a separate experiment with extended self-awareness dopamine improved the retrieval accuracy of memories of self-judgment (autonoetic, i.e., explicitly self-conscious) metacognition. Concomitantly, magnetoencephalography (MEG) showed increased amplitudes of oscillations (power) preferentially in the medial prefrontal cortex. Given that electromagnetic activity in this region is instrumental in self-awareness, this explains the specific effect of dopamine on explicit self-awareness and autonoetic metacognition.
Collapse
Affiliation(s)
- Morten Joensson
- Center of Functionally Integrative Neuroscience, Aarhus University, 8000, Aarhus, Denmark; Department of Psychiatry, University of Oxford, OX37JX Oxford, United Kingdom
| | | | | | | | | | | | | | | |
Collapse
|
6
|
Affiliation(s)
- Zoran Josipovic
- Psychology Department; New York University; New York New York
| |
Collapse
|
7
|
Affiliation(s)
- Zoran Josipovic
- Contemplative Science Lab, Department of Psychology, New York University New York, NY, USA
| |
Collapse
|
8
|
Tsuchiya N, van Boxtel J. Introduction to research topic: attention and consciousness in different senses. Front Psychol 2013; 4:249. [PMID: 23641230 PMCID: PMC3640185 DOI: 10.3389/fpsyg.2013.00249] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 04/15/2013] [Indexed: 12/02/2022] Open
Affiliation(s)
- Naotsugu Tsuchiya
- Faculty of Medicine, Nursing and Health Sciences, School of Psychology and Psychiatry, Monash UniversityMelbourne, VIC, Australia
- Japan Science and Technology AgencyTokyo, Japan
| | - Jeroen van Boxtel
- Department of Psychology, University of California Los AngelesLos Angeles, CA, USA
- Division of Biology, California Institute of TechnologyPasadena, CA, USA
| |
Collapse
|
9
|
Abstract
The introduction of magnetoencephalography has made it possible to study electromagnetic signaling in deeper, paralimbic cortical structures such as the medial prefrontal/anterior cingulate (ACC) and medial parietal/posterior cingulate (PCC) cortices. Self-awareness and self-control have been attributed to these regions. To test the hypothesis that they are dysfunctional in pathological gambling with poor self-control, we studied gamblers with and without previous stimulant abuse and age- and sex-matched controls. We found that pathological gamblers were more impulsive than controls in a stop-signal task and attributed this to changes in the activity of the paralimbic network: Pathological gamblers had reduced synchronization at rest in the high gamma range (55-100 Hz) compared with controls and failed to show an increase in gamma synchronization during rest compared with the task, as observed in controls. Subgroup analysis revealed that pathological gamblers without a history of stimulant abuse had lower PCC power during the stop-signal task compared with controls and gamblers with previous stimulant abuse. Furthermore, gamblers with a history of stimulant abuse had up to four times higher power at the ACC site during rest and the task compared with controls. In conclusion, pathological gamblers had higher impulsivity and functional paralimbic abnormalities, which could not be explained by a history of stimulant abuse. In addition, previous stimulant abuse had a marked effect on the amplitude of oscillatory brain activity in the ACC and PCC, suggesting long-term deleterious effects of repeated dopaminergic drug exposure. These consequences should be investigated in more detail in longitudinal studies.
Collapse
|
10
|
Quah-Smith I, Wen W, Chen X, Williams MA, Sachdev PS. The Brain Effects of Laser Acupuncture in Depressed Individuals: An fMRI Investigation. Med Acupunct 2012. [DOI: 10.1089/acu.2011.0870] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Affiliation(s)
- Im Quah-Smith
- School of Psychiatry, Faculty of Medicine, University of New South Wales, New South Wales, Australia
| | - Wei Wen
- School of Psychiatry, Faculty of Medicine, University of New South Wales, New South Wales, Australia
- Neuropsychiatric Institute, Prince of Wales Hospital, Randwick, New South Wales, Australia
- Brain & Ageing Research Program, School of Psychiatry, Faculty of Medicine, University of New South Wales, New South Wales, Australia
| | - Xiaohua Chen
- School of Psychiatry, Faculty of Medicine, University of New South Wales, New South Wales, Australia
- Neuropsychiatric Institute, Prince of Wales Hospital, Randwick, New South Wales, Australia
- Brain & Ageing Research Program, School of Psychiatry, Faculty of Medicine, University of New South Wales, New South Wales, Australia
| | - Mark A. Williams
- Macquarie Centre for Cognitive Sciences, Macquarie University, Sydney, Australia
| | - Perminder S. Sachdev
- School of Psychiatry, Faculty of Medicine, University of New South Wales, New South Wales, Australia
- Neuropsychiatric Institute, Prince of Wales Hospital, Randwick, New South Wales, Australia
- Brain & Ageing Research Program, School of Psychiatry, Faculty of Medicine, University of New South Wales, New South Wales, Australia
| |
Collapse
|
11
|
Georgiadis JR, Kringelbach ML. The human sexual response cycle: brain imaging evidence linking sex to other pleasures. Prog Neurobiol 2012; 98:49-81. [PMID: 22609047 DOI: 10.1016/j.pneurobio.2012.05.004] [Citation(s) in RCA: 190] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Revised: 04/21/2012] [Accepted: 05/08/2012] [Indexed: 12/30/2022]
Abstract
Sexual behavior is critical to species survival, yet comparatively little is known about the neural mechanisms in the human brain. Here we systematically review the existing human brain imaging literature on sexual behavior and show that the functional neuroanatomy of sexual behavior is comparable to that involved in processing other rewarding stimuli. Sexual behavior clearly follows the established principles and phases for wanting, liking and satiety involved in the pleasure cycle of other rewards. The studies have uncovered the brain networks involved in sexual wanting or motivation/anticipation, as well as sexual liking or arousal/consummation, while there is very little data on sexual satiety or post-orgasmic refractory period. Human sexual behavior also interacts with other pleasures, most notably social interaction and high arousal states. We discuss the changes in the underlying brain networks supporting sexual behavior in the context of the pleasure cycle, the changes to this cycle over the individual's life-time and the interactions between them. Overall, it is clear from the data that the functional neuroanatomy of sex is very similar to that of other pleasures and that it is unlikely that there is anything special about the brain mechanisms and networks underlying sex.
Collapse
Affiliation(s)
- J R Georgiadis
- Department of Neuroscience/Section Anatomy, University Medical Center Groningen (UMCG), University of Groningen, Groningen, The Netherlands.
| | | |
Collapse
|
12
|
The functional human neuroanatomy of food pleasure cycles. Physiol Behav 2012; 106:307-16. [PMID: 22487544 DOI: 10.1016/j.physbeh.2012.03.023] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2011] [Revised: 02/28/2012] [Accepted: 03/20/2012] [Indexed: 01/01/2023]
Abstract
Food ensures our survival and is a potential source of pleasure and general well-being. In order to survive, the human brain is required to optimize the resource allocation such that rewards are pursued when relevant. This means that food intake follows a similar cyclical time course to other rewards with phases related to expectation, consummation and satiety. Here we develop a multilevel model for the full cycle of eating behavior based on the evidence for the brain networks and mechanisms initiating, sustaining and terminating the various phases of eating. We concentrate on how the underlying reward mechanisms of wanting, liking and learning lead to how human food intake is governed by both hedonic and homeostatic principles. We describe five of the main processing principles controlling food intake: hunger and attentional signal processing; motivation-independent discriminative processing; reward representations; learning-dependent multimodal sensory representations and hedonic experience. Overall, the evidence shows that while human food intake is complex, we are making progress in understanding the underlying mechanisms and that the brain networks supporting the food pleasure cycle are remarkably similar to those underlying the processing of other rewards.
Collapse
|