The Roles of Dorsolateral Prefrontal Cortex and Posterior Parietal Cortex During Task Switching

Both dorsolateral prefrontal and posterior parietal cortex have been implicated in spatial working memory and representation of task information. Prior experiments training animals to recall the first of a sequence of stimuli and examining the effect of subsequent distractors have identified increased ability of the prefrontal cortex to represent remembered stimuli and filter distractors. It is unclear, however, if this prefrontal functional specialization extends to stimuli appearing earlier in a sequence, when subjects are cued to remember subsequent ones. It is also not known how task information interacts with persistent activity representing remembered stimuli and distractors in the two areas. To address these questions, we trained monkeys to remember either the first or second of two stimuli presented in sequence and recorded neuronal activity from the posterior parietal and dorsolateral prefrontal cortex. The prefrontal cortex was better able to represent the actively remembered stimulus, whereas the posterior parietal cortex was more modulated by distractors; however, task effects interfered with this representation. As a result, large proportions of neurons with persistent activity and task effects exhibited a preference for a stimulus when it appeared as a distractor in both areas. Additionally, prefrontal neurons were modulated to a greater extent by task factors during the delay period of the task. The results indicate that the prefrontal cortex is better able than the posterior parietal cortex to differentiate between distractors and actively remembered stimuli and is more modulated by the task; however, this relative preference is highly context dependent and depends on the specific requirements of the task.

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Neurons with inverted tuning during the delay periods of working memory tasks in the dorsal prefrontal and posterior parietal cortex

Journal of Neurophysiology ◽

10.1152/jn.01151.2011 ◽

2012 ◽

Vol 108 (1) ◽

pp. 31-38 ◽

Cited By ~ 16

Author(s):

Xin Zhou ◽

Fumi Katsuki ◽

Xue-Lian Qi ◽

Christos Constantinidis

Keyword(s):

Working Memory ◽

Prefrontal Cortex ◽

Parietal Cortex ◽

Posterior Parietal Cortex ◽

Memory Task ◽

Functional Difference ◽

Initial Stimulus ◽

Cortical Afferents ◽

Dorsolateral Prefrontal ◽

Posterior Parietal

The dorsolateral prefrontal and posterior parietal cortices are two interconnected brain areas that are coactivated in tasks involving functions such as spatial attention and working memory. The response properties of neurons in the two areas are in many respects indistinguishable, yet only prefrontal neurons are able to resist interference by distracting stimuli when subjects are required to remember an initial stimulus. Several mechanisms have been proposed that could account for this functional difference, including the existence of specialized interneuron types, specific to the prefrontal cortex. Although such neurons with inverted tuning during the delay period of a working memory task have been described in the prefrontal cortex, no comparative data exist from other cortical areas that would establish a unique prefrontal role. To test this hypothesis, we analyzed a large database of recordings obtained in the dorsolateral prefrontal and posterior parietal cortex of the same monkeys as they performed working memory tasks. We found that in the prefrontal cortex, neurons with inverted tuning were more numerous and manifested unique properties. Our results give credence to the idea that a division of labor exists between separate neuron types in the prefrontal cortex and that this represents a functional specialization that is not present in its cortical afferents.

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The role of prefrontal cortex and posterior parietal cortex in task switching

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.240460497 ◽

2000 ◽

Vol 97 (24) ◽

pp. 13448-13453 ◽

Cited By ~ 354

Author(s):

M.-H. Sohn ◽

S. Ursu ◽

J. R. Anderson ◽

V. A. Stenger ◽

C. S. Carter

Keyword(s):

Prefrontal Cortex ◽

Parietal Cortex ◽

Task Switching ◽

Posterior Parietal Cortex ◽

Posterior Parietal

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Social hyperscanning with fNIRS

Gesture ◽

10.1075/gest.20013.bal ◽

2020 ◽

Vol 19 (2-3) ◽

pp. 196-222

Author(s):

Michela Balconi ◽

Angela Bartolo ◽

Giulia Fronda

Keyword(s):

Prefrontal Cortex ◽

Infrared Spectroscopy ◽

Near Infrared Spectroscopy ◽

Dorsolateral Prefrontal Cortex ◽

Near Infrared ◽

Brain Connectivity ◽

Gestural Communication ◽

Functional Near Infrared Spectroscopy ◽

Dorsolateral Prefrontal ◽

Posterior Parietal

Abstract The interest of neuroscience has been aimed at the investigation of the neural bases underlying gestural communication. This research explored the intra- and inter-brain connectivity between encoder and decoder. Specifically, adopting a “hyperscanning paradigm” with the functional Near-infrared Spectroscopy (fNIRS) cerebral connectivity in oxygenated (O2Hb) and deoxygenated (HHb) hemoglobin levels were revealed during the reproduction of affective, social, and informative gestures of different valence. Results showed an increase of intra- and inter-brain connectivity in dorsolateral prefrontal cortex for affective gestures, in superior frontal gyrus for social gestures and in frontal eyes field for informative gestures. Moreover, encoder showed a higher intra-brain connectivity in posterior parietal areas more than decoder. Finally, an increasing of inter-brain connectivity more than intra-brain (ConIndex) was observed in left regions for positive gestures. The present research has explored how the individuals neural tuning mechanisms turn out to be strongly influenced by the nature of specific gestures.

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Experience-Dependent Neural Integration of Taste and Smell in the Human Brain

Journal of Neurophysiology ◽

10.1152/jn.00050.2004 ◽

2004 ◽

Vol 92 (3) ◽

pp. 1892-1903 ◽

Cited By ~ 248

Author(s):

Dana M. Small ◽

Joel Voss ◽

Y. Erica Mak ◽

Katharine B. Simmons ◽

Todd Parrish ◽

...

Keyword(s):

Prefrontal Cortex ◽

Parietal Cortex ◽

Posterior Parietal Cortex ◽

Anterior Cingulate ◽

Brain Response ◽

Liquid Form ◽

Flavor Perception ◽

Odor Pair ◽

Frontal Operculum ◽

Posterior Parietal

Flavor perception arises from the central integration of peripherally distinct sensory inputs (taste, smell, texture, temperature, sight, and even sound of foods). The results from psychophysical and neuroimaging studies in humans are converging with electrophysiological findings in animals and a picture of the neural correlates of flavor processing is beginning to emerge. Here we used event-related fMRI to evaluate brain response during perception of flavors (i.e., taste/odor liquid mixtures not differing in temperature or texture) compared with the sum of the independent presentation of their constituents (taste and/or odor). All stimuli were presented in liquid form so that olfactory stimulation was by the retronasal route. Mode of olfactory delivery is important because neural suppression has been observed in chemosensory regions during congruent taste–odor pairs when the odors are delivered by the orthonasal route and require subjects to sniff. There were 2 flavors. One contained a familiar/congruent taste–odor pair (vanilla/sweet) and the other an unfamiliar/incongruent taste–odor pair (vanilla/salty). Three unimodal stimuli, including 2 tastes (sweet and salty) and one odor (vanilla), as well as a tasteless/odorless liquid (baseline) were presented. Superadditive responses during the perception of the congruent flavor compared with the sum of its constituents were observed in the anterior cingulate cortex (ACC), dorsal insula, anterior ventral insula extending into the caudal orbitofrontal cortex (OFC), frontal operculum, ventral lateral prefrontal cortex, and posterior parietal cortex. These regions were not present in a similar analysis of the incongruent flavor compared with the sum of its constituents. All of these regions except the ventrolateral prefrontal cortex were also isolated in a direct contrast of congruent − incongruent. Additionally, the anterior cingulate, posterior parietal cortex, frontal operculum, and ventral insula/caudal OFC were also more active in vanilla + salty minus incongruent, suggesting that delivery of an unfamiliar taste–odor combination may lead to suppressed neural responses. Taken together with previous findings in the literature, these results suggest that the insula, OFC, and ACC are key components of the network underlying flavor perception and that taste–smell integration within these and other regions is dependent on 1) mode of olfactory delivery and 2) previous experience with taste/smell combinations.

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Effects of repetitive transcranial magnetic stimulation over dorsolateral prefrontal and posterior parietal cortex on memory-guided saccades

Experimental Brain Research ◽

10.1007/s002210050272 ◽

1998 ◽

Vol 118 (2) ◽

pp. 197-204 ◽

Cited By ~ 46

Author(s):

S. A. Brandt ◽

Christoph J. Ploner ◽

Bernd-Ulrich Meyer ◽

Stefanie Leistner ◽

Arno Villringer

Keyword(s):

Transcranial Magnetic Stimulation ◽

Parietal Cortex ◽

Magnetic Stimulation ◽

Posterior Parietal Cortex ◽

Repetitive Transcranial Magnetic Stimulation ◽

Dorsolateral Prefrontal ◽

Posterior Parietal

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Brain functional changes across the different phases of bipolar disorder

The British Journal of Psychiatry ◽

10.1192/bjp.bp.114.152033 ◽

2015 ◽

Vol 206 (2) ◽

pp. 136-144 ◽

Cited By ~ 34

Author(s):

Edith Pomarol-Clotet ◽

Silvia Alonso-Lana ◽

Noemi Moro ◽

Salvador Sarró ◽

Mar C. Bonnin ◽

...

Keyword(s):

Bipolar Disorder ◽

Prefrontal Cortex ◽

Frontal Cortex ◽

Parietal Cortex ◽

Dorsolateral Prefrontal Cortex ◽

Cognitive Task ◽

Memory Task ◽

Mixed Effects ◽

Linear Mixed Effects ◽

Dorsolateral Prefrontal

BackgroundLittle is known about how functional imaging changes in bipolar disorder relate to different phases of the illness.AimsTo compare cognitive task activation in participants with bipolar disorder examined in different phases of illness.MethodParticipants with bipolar disorder in mania (n = 38), depression (n = 38) and euthymia (n = 38), as well as healthy controls (n = 38), underwent functional magnetic resonance imaging during performance of the n-back working memory task. Activations and de-activations were compared between the bipolar subgroups and the controls, and among the bipolar subgroups. All participants were also entered into a linear mixed-effects model.ResultsCompared with the controls, the mania and depression subgroups, but not the euthymia subgroup, showed reduced activation in the dorsolateral prefrontal cortex, the parietal cortex and other areas. Compared with the euthymia subgroup, the mania and depression subgroups showed hypoactivation in the parietal cortex. All three bipolar subgroups showed failure of de-activation in the ventromedial frontal cortex. Linear mixed-effects modelling revealed a further cluster of reduced activation in the left dorsolateral prefrontal cortex in the patients; this was significantly more marked in the mania than in the euthymia subgroup.ConclusionsBipolar disorder is characterised by mood state-dependent hypoactivation in the parietal cortex. Reduced dorsolateral prefrontal activation is a further feature of mania and depression, which may improve partially in euthymia. Failure of de-activation in the medial frontal cortex shows trait-like characteristics.

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