Task-positive network

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The task-positive network (TPN) is a network of areas in the human brain that typically responds with activation increases to attention-demanding tasks in functional imaging studies.[1] The task-positive network encompasses regions of the dorsal attention system, but in addition includes dorsolateral and ventrolateral prefrontal regions, the insular cortex, and the SMA/pre-SMA.[1] Recent work indicates that the cerebellum may participate in this network as well.[2][3] Notably, the nodes of this network are also correlated during rest (i.e., in the absence of any task).[1] The task-positive network is anti-correlated with the default mode network.[1][4] Competing activation between the task-positive network and the default mode network at the time of memory encoding has been shown to result in poor long-term memory consolidation.[5]

During rest the TPN has been claimed to subserve intermittent "external awareness", defined as the conscious perception through different sensory modalities of one's surrounding environment[further explanation needed].[6]

Function[edit]

During performance of attention-demanding tasks, prefrontal and parietal structures comprising the task-positive network are characterized by increases in activation; in contrast, default mode network structures, including posterior cingulate[further explanation needed] and medial prefrontal cortices, are characterized by decreased activity. During wakeful rest, the opposite pattern emerges, with the default mode network becoming more active and the task-positive network less active.[7]

References[edit]

  1. ^ a b c d Fox, M. D.; Snyder, A. Z.; Vincent, J. L.; Corbetta, M.; Van Essen, D. C.; Raichle, M. E. (2005). "From The Cover: The human brain is intrinsically organized into dynamic, anticorrelated functional networks". Proceedings of the National Academy of Sciences. 102 (27): 9673–9678. doi:10.1073/pnas.0504136102. ISSN 0027-8424. PMC 1157105. PMID 15976020.
  2. ^ Somers, David C.; Halko, Mark A.; Levin, Emily J.; Osher, David E.; Tobyne, Sean M.; Brissenden, James A. (2018-11-05). "Topographic Cortico-cerebellar Networks Revealed by Visual Attention and Working Memory". Current Biology. 28 (21): 3364–3372.e5. doi:10.1016/j.cub.2018.08.059. ISSN 0960-9822. PMID 30344119.
  3. ^ Somers, David C.; Halko, Mark A.; Osher, David E.; Levin, Emily J.; Brissenden, James A. (2016-06-01). "Functional Evidence for a Cerebellar Node of the Dorsal Attention Network". Journal of Neuroscience. 36 (22): 6083–6096. doi:10.1523/JNEUROSCI.0344-16.2016. ISSN 0270-6474. PMID 27251628.
  4. ^ Fransson, P. (2005). "Spontaneous low-frequency BOLD signal fluctuations: an fMRI investigation of the resting-state default mode of brain function hypothesis". Human Brain Mapping. 26 (1): 15–29. doi:10.1002/hbm.20113. PMID 15852468.
  5. ^ Lefebvre, Etienne; D’Angiulli, Amedeo (2019). "Imagery-Mediated Verbal Learning Depends on Vividness–Familiarity Interactions: The Possible Role of Dualistic Resting State Network Activity Interference". Brain Sciences. 9 (6): 143. doi:10.3390/brainsci9060143. ISSN 2076-3425.
  6. ^ Vanhaudenhuyse, Audrey; Demertzi, Athena; Schabus, Manuel; Noirhomme, Quentin; Bredart, Serge; Boly, Melanie; Phillips, Christophe; Soddu, Andrea; Luxen, Andre; Moonen, Gustave; Laureys, Steven (1 March 2011). "Two Distinct Neuronal Networks Mediate the Awareness of Environment and of Self". Journal of Cognitive Neuroscience. 23 (3): 570–578. doi:10.1162/jocn.2010.21488. PMID 20515407.
  7. ^ Hamilton, J.Paul (2011). "Default-Mode and Task-Positive Network Activity in Major Depressive Disorder: Implications for Adaptive and Maladaptive Rumination" (PDF). Biological Psychiatry. 70 (4): 327–333. doi:10.1016/j.biopsych.2011.02.003. PMC 3144981. PMID 21459364. Retrieved 6 June 2014.