51
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Sauvage A, Hubert G, Touboul J, Ribot J. The hemodynamic signal as a first-order low-pass temporal filter: Evidence and implications for neuroimaging studies. Neuroimage 2017; 155:394-405. [PMID: 28343986 DOI: 10.1016/j.neuroimage.2017.03.053] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 02/28/2017] [Accepted: 03/23/2017] [Indexed: 01/26/2023] Open
Abstract
Neuronal activation triggers local changes in blood flow and hemoglobin oxygenation. These hemodynamic signals can be recorded through functional magnetic resonance imaging or intrinsic optical imaging, and allows inferring neural activity in response to stimuli. These techniques are widely used to uncover functional brain architectures. However, their accuracy suffers from distortions inherent to hemodynamic responses and noise. The analysis of these signals currently relies on models of impulse hemodynamic responses to brief stimuli. Here, in order to infer precise functional architectures, we focused on integrated signals associated to the dynamic response of functional maps. To this end, we recorded orientation and direction maps in cat primary visual cortex and compared two protocols: the conventional episodic stimulation technique and a continuous, periodic stimulation paradigm. Conventional methods show that the dynamics of activation and deactivation of the functional maps follows a linear first-order differential equation representing a low-pass filter. Comparison with the periodic stimulation methods confirmed this observation: the phase shifts and magnitude attenuations extracted at various frequencies were consistent with a low-pass filter with a 5s time constant. This dynamics presumably reflects the variations in deoxyhemoglobin mediated by arterial dilations. This dynamics open new avenues in the analysis of neuroimaging data that differs from common methods based on the hemodynamic response function. In particular, we demonstrate that inverting this first-order low-pass filter minimized the distortions of the signal and enabled a much faster and accurate reconstruction of functional maps.
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Affiliation(s)
- Antoine Sauvage
- Mathematical Neuroscience Team, CIRB - Collège de France (CNRS UMR 7241, INSERM U1050, UPMC ED 158, MEMOLIFE PSL), 11 Place Marcelin Berthelot, 75005 Paris, France
| | - Guillaume Hubert
- Mathematical Neuroscience Team, CIRB - Collège de France (CNRS UMR 7241, INSERM U1050, UPMC ED 158, MEMOLIFE PSL), 11 Place Marcelin Berthelot, 75005 Paris, France
| | - Jonathan Touboul
- Mathematical Neuroscience Team, CIRB - Collège de France (CNRS UMR 7241, INSERM U1050, UPMC ED 158, MEMOLIFE PSL), 11 Place Marcelin Berthelot, 75005 Paris, France; INRIA Mycenae Team, Paris-Rocquencourt, France
| | - Jérôme Ribot
- Mathematical Neuroscience Team, CIRB - Collège de France (CNRS UMR 7241, INSERM U1050, UPMC ED 158, MEMOLIFE PSL), 11 Place Marcelin Berthelot, 75005 Paris, France.
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52
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Neural dynamics underlying varying attentional control facing invariant cognitive task upon invariant stimuli. Neuroscience 2017; 353:133-146. [DOI: 10.1016/j.neuroscience.2017.04.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 03/28/2017] [Accepted: 04/18/2017] [Indexed: 11/22/2022]
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53
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Neta M, Nelson SM, Petersen SE. Dorsal Anterior Cingulate, Medial Superior Frontal Cortex, and Anterior Insula Show Performance Reporting-Related Late Task Control Signals. Cereb Cortex 2017; 27:2154-2165. [PMID: 26972752 DOI: 10.1093/cercor/bhw053] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The cingulo-opercular network (including the dorsal anterior cingulate and bilateral anterior insula) shows 3 distinct task-control signals across a wide variety of tasks, including trial-related signals that appear to come online at or near the end of the trial. Previous work suggests that there are separable responses in this network for errors and ambiguity, implicating multiple types of processing units within these regions. Using a unique paradigm, we directly show that these separable responses withhold activity to the end of the trial, in the service of reporting performance back into the task set. Participants performed a slow reveal task where images were presented behind a black mask which was gradually degraded, and they pressed a button when they could recognize the object that was being revealed. A behavioral pilot was used to identify ambiguous stimuli. We found interactive effects of accuracy and ambiguity, which suggests that these regions are computing and utilizing information, at one time, about both types of performance indices. Importantly, we showed a relationship between cingulo-opercular activity and behavioral performance, suggesting a role for these regions in performance reporting, per se. We discuss these results in the context of task control.
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Affiliation(s)
- Maital Neta
- Department of Psychology, University of Nebraska-Lincoln, Lincoln, NE68588, USA
| | - Steven M Nelson
- VISN 17 Center of Excellence for Research on Returning War Veterans, Waco, TX 76711, USA.,Center for Vital Longevity, School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, TX 75235, USA
| | - Steven E Petersen
- Department of Neurology, Washington University, St. Louis, MO 63110, USA.,Department of Psychology, Washington University, St. Louis, MO 63110, USA.,Department of Radiology, Washington University, St. Louis, MO 63110, USA.,Department of Anatomy and Neurobiology, Washington University, St. Louis, MO 63110, USA.,Department of Neurosurgery, Washington University, St. Louis, MO 63110, USA.,Biomedical Engineering, Washington University, St. Louis, MO 63110, USA
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54
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Gratton C, Neta M, Sun H, Ploran EJ, Schlaggar BL, Wheeler ME, Petersen SE, Nelson SM. Distinct Stages of Moment-to-Moment Processing in the Cinguloopercular and Frontoparietal Networks. Cereb Cortex 2017; 27:2403-2417. [PMID: 27095824 DOI: 10.1093/cercor/bhw092] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Control of goal-directed tasks is putatively carried out via the cinguloopercular (CO) and frontoparietal (FP) systems. However, it remains unclear whether these systems show dissociable moment-to-moment processing during distinct stages of a trial. Here, we characterize dynamics in the CO and FP networks in a meta-analysis of 5 decision-making tasks using fMRI, with a specialized "slow reveal" paradigm which allows us to measure the temporal characteristics of trial responses. We find that activations in left FP, right FP, and CO systems form separate clusters, pointing to distinct roles in decision-making. Left FP shows early "accumulator-like" responses, suggesting a role in pre-decision processing. CO has a late onset and transient response linked to the decision event, suggesting a role in performance reporting. The majority of right FP regions show late onsets with prolonged responses, suggesting a role in post-recognition processing. These findings expand upon past models, arguing that the CO and FP systems relate to distinct stages of processing within a trial. Furthermore, the findings provide evidence for a heterogeneous profile in the FP network, with left and right FP taking on specialized roles. This evidence informs our understanding of how distinct control networks may coordinate moment-to-moment components of complex actions.
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Affiliation(s)
| | - M Neta
- Department of Psychology, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - H Sun
- Department of Biomedical Engineering
| | - E J Ploran
- Department of Psychology, Hofstra University, Hempstead, NY, USA
| | - B L Schlaggar
- Department of Neurology.,Department of Radiology.,Department of Pediatrics.,Department of Neuroscience
| | - M E Wheeler
- School of Psychology, Georgia Institute of Technology, Atlanta, GA, USA
| | - S E Petersen
- Department of Neurology.,Department of Radiology.,Department of Neuroscience.,Department of Biomedical Engineering.,Department of Psychology and.,Department of Neurological Surgery, Washington University in St Louis, St Louis, MO, USA
| | - S M Nelson
- VISN 17 Center of Excellence for Research on Returning War Veterans, Waco, TX, USA.,Center for Vital Longevity, School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, TX, USA
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55
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Sussman TJ, Weinberg A, Szekely A, Hajcak G, Mohanty A. Here Comes Trouble: Prestimulus Brain Activity Predicts Enhanced Perception of Threat. Cereb Cortex 2017; 27:2695-2707. [PMID: 27114179 DOI: 10.1093/cercor/bhw104] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Research on the perceptual prioritization of threatening stimuli has focused primarily on the physical characteristics and evolutionary salience of these stimuli. However, perceptual decision-making is strongly influenced by prestimulus factors such as goals, expectations, and prior knowledge. Using both event-related potentials and functional magnetic resonance imaging, we test the hypothesis that prior threat-related information and related increases in prestimulus brain activity play a key role in subsequent threat-related perceptual decision-making. After viewing threatening and neutral cues, participants detected perceptually degraded threatening and neutral faces presented at individually predetermined perceptual thresholds in a perceptual decision-making task. Compared with neutral cues, threat cues resulted in (1) improved perceptual sensitivity and faster detection of target stimuli; (2) increased late positive potential (LPP) and superior temporal sulcus (STS) activity, both of which are measures of emotional face processing; and (3) increased amygdala activity for subsequently presented threatening versus and neutral faces. Importantly, threat cue-related LPP and STS activity predicted subsequent improvement in the speed and precision of perceptual decisions specifically for threatening faces. Present findings establish the importance of top-down factors and prestimulus neural processing in understanding how the perceptual system prioritizes threatening information.
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Affiliation(s)
- Tamara J Sussman
- Department of Psychology, Stony Brook University, Stony Brook, NY 11794-2500, USA
| | - Anna Weinberg
- Department of Psychology, McGill University, Montreal H3A 2B4, Quebec, Canada
| | - Akos Szekely
- Department of Psychology, Stony Brook University, Stony Brook, NY 11794-2500, USA
| | - Greg Hajcak
- Department of Psychology, Stony Brook University, Stony Brook, NY 11794-2500, USA
| | - Aprajita Mohanty
- Department of Psychology, Stony Brook University, Stony Brook, NY 11794-2500, USA
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56
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Aarabi A, Osharina V, Wallois F. Effect of confounding variables on hemodynamic response function estimation using averaging and deconvolution analysis: An event-related NIRS study. Neuroimage 2017; 155:25-49. [PMID: 28450140 DOI: 10.1016/j.neuroimage.2017.04.048] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 04/12/2017] [Accepted: 04/20/2017] [Indexed: 11/17/2022] Open
Abstract
Slow and rapid event-related designs are used in fMRI and functional near-infrared spectroscopy (fNIRS) experiments to temporally characterize the brain hemodynamic response to discrete events. Conventional averaging (CA) and the deconvolution method (DM) are the two techniques commonly used to estimate the Hemodynamic Response Function (HRF) profile in event-related designs. In this study, we conducted a series of simulations using synthetic and real NIRS data to examine the effect of the main confounding factors, including event sequence timing parameters, different types of noise, signal-to-noise ratio (SNR), temporal autocorrelation and temporal filtering on the performance of these techniques in slow and rapid event-related designs. We also compared systematic errors in the estimates of the fitted HRF amplitude, latency and duration for both techniques. We further compared the performance of deconvolution methods based on Finite Impulse Response (FIR) basis functions and gamma basis sets. Our results demonstrate that DM was much less sensitive to confounding factors than CA. Event timing was the main parameter largely affecting the accuracy of CA. In slow event-related designs, deconvolution methods provided similar results to those obtained by CA. In rapid event-related designs, our results showed that DM outperformed CA for all SNR, especially above -5 dB regardless of the event sequence timing and the dynamics of background NIRS activity. Our results also show that periodic low-frequency systemic hemodynamic fluctuations as well as phase-locked noise can markedly obscure hemodynamic evoked responses. Temporal autocorrelation also affected the performance of both techniques by inducing distortions in the time profile of the estimated hemodynamic response with inflated t-statistics, especially at low SNRs. We also found that high-pass temporal filtering could substantially affect the performance of both techniques by removing the low-frequency components of HRF profiles. Our results emphasize the importance of characterization of event timing, background noise and SNR when estimating HRF profiles using CA and DM in event-related designs.
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Affiliation(s)
- Ardalan Aarabi
- Faculty of Medicine, University of Picardie Jules Verne, Amiens 80036, France; GRAMFC-Inserm U1105, University Research Center (CURS), University Hospital, Amiens, 80054 France.
| | - Victoria Osharina
- GRAMFC-Inserm U1105, University Research Center (CURS), University Hospital, Amiens, 80054 France
| | - Fabrice Wallois
- GRAMFC-Inserm U1105, University Research Center (CURS), University Hospital, Amiens, 80054 France; EFSN Pediatric (Pediatric Nervous System Functional Investigation Unit), CHU AMIENS - SITE SUD, Amiens, France
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57
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Tosoni A, Committeri G, Calluso C, Galati G. The effect of reward expectation on the time course of perceptual decisions. Eur J Neurosci 2017; 45:1152-1164. [DOI: 10.1111/ejn.13555] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 02/02/2017] [Accepted: 02/23/2017] [Indexed: 11/28/2022]
Affiliation(s)
- Annalisa Tosoni
- Department of Neuroscience, Imaging and Clinical Sciences; G. D'Annunzio University; Via dei Vestini 33 66013 Chieti Italy
- Institute for Advanced Biomedical Technologies; G. D'Annunzio Foundation; Chieti Italy
| | - Giorgia Committeri
- Department of Neuroscience, Imaging and Clinical Sciences; G. D'Annunzio University; Via dei Vestini 33 66013 Chieti Italy
- Institute for Advanced Biomedical Technologies; G. D'Annunzio Foundation; Chieti Italy
| | - Cinzia Calluso
- Department of Neuroscience, Imaging and Clinical Sciences; G. D'Annunzio University; Via dei Vestini 33 66013 Chieti Italy
- Institute for Advanced Biomedical Technologies; G. D'Annunzio Foundation; Chieti Italy
| | - Gaspare Galati
- Department of Psychology; Sapienza University of Rome; Rome Italy
- Laboratory of Neuropsychology; Santa Lucia Foundation; Rome Italy
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58
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Abstract
Parahippocampal cortex (PHc) is known to process spatial information, both in perceptual and episodic memory studies. However, recent theories propose an expanded role for PHc in processing context information in general, whether spatial or nonspatial. The current study used a source memory paradigm to investigate encoding and retrieval of nonspatial context information. Human participants were asked to judge lexical aspects of word stimuli and to retrieve those judgments during a later memory test. Anterior PHc showed significantly greater activation for items associated with correct source judgments than items associated with incorrect source judgments during both encoding and retrieval phases. These findings suggest that the role of PHc in episodic memory cannot be limited to spatial information.
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Affiliation(s)
- Rachel A. Diana
- Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
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59
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Church JA, Bunge SA, Petersen SE, Schlaggar BL. Preparatory Engagement of Cognitive Control Networks Increases Late in Childhood. Cereb Cortex 2017; 27:2139-2153. [PMID: 26972753 PMCID: PMC6317491 DOI: 10.1093/cercor/bhw046] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The ability to engage task control flexibly, especially in anticipation of task demands, is beneficial when juggling different tasks. We investigated whether children in late childhood or early adolescence engaged preparatory task control similar to adults in a trial-wise cued task-switching paradigm. Twenty-eight children (aged 9-15 years) and 30 adults (aged 21-30 years) participated in an fMRI study in which the Cue (preparatory) period across 2 tasks was analyzed separately from the execution of the tasks (the Target period). Children performed more slowly and less accurately than adults, and showed behavioral improvement within the child group age range of 9-15 years. Children exhibited weaker Cue period activation than adults within a number of putative cognitive control regions. In contrast, children exhibited greater activity than adults in several regions, including sensorimotor areas, during the Target period. Children who activated cognitive control-related regions more during the Cue period tended to activate the Target signal age-related regions less, and this correlated with improved accuracy and reaction time on the task, as well as age. The results endorse previous findings that preparatory cognitive control systems are still developing in late childhood, but add new evidence of age-related shifts in activity at the trial level.
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Affiliation(s)
- Jessica A. Church
- Department of Psychology, The University of Texas at Austin, Austin, TX 78712, USA
| | - Silvia A. Bunge
- Helen Wills Neuroscience Institute
- Department of Psychology, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Steven E. Petersen
- Department of Neurology
- Department of Radiology
- Department of Anatomy and Neurobiology
- Department of Neurosurgery
- Department of Psychology
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO63130, USA
| | - Bradley L. Schlaggar
- Department of Neurology
- Department of Radiology
- Department of Anatomy and Neurobiology
- Department of Pediatrics
- Department of Psychiatry, Washington University School of Medicine in St. Louis, St. Louis, MO 63110, USA
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60
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Turner BO, Crossley MJ, Ashby FG. Hierarchical control of procedural and declarative category-learning systems. Neuroimage 2017; 150:150-161. [PMID: 28213114 DOI: 10.1016/j.neuroimage.2017.02.039] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 01/30/2017] [Accepted: 02/13/2017] [Indexed: 01/30/2023] Open
Abstract
Substantial evidence suggests that human category learning is governed by the interaction of multiple qualitatively distinct neural systems. In this view, procedural memory is used to learn stimulus-response associations, and declarative memory is used to apply explicit rules and test hypotheses about category membership. However, much less is known about the interaction between these systems: how is control passed between systems as they interact to influence motor resources? Here, we used fMRI to elucidate the neural correlates of switching between procedural and declarative categorization systems. We identified a key region of the cerebellum (left Crus I) whose activity was bidirectionally modulated depending on switch direction. We also identified regions of the default mode network (DMN) that were selectively connected to left Crus I during switching. We propose that the cerebellum-in coordination with the DMN-serves a critical role in passing control between procedural and declarative memory systems.
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61
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Hawes SW, Chahal R, Hallquist MN, Paulsen DJ, Geier CF, Luna B. Modulation of reward-related neural activation on sensation seeking across development. Neuroimage 2017; 147:763-771. [PMID: 27956207 PMCID: PMC5303670 DOI: 10.1016/j.neuroimage.2016.12.020] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Revised: 12/04/2016] [Accepted: 12/08/2016] [Indexed: 11/30/2022] Open
Abstract
Sensation seeking is a personality construct associated with an increased propensity for engaging in risk-taking. Associations with deleterious outcomes ranging from mental health impairments to increased mortality rates highlight important public health concerns related to this construct. Although some have suggested that increased neural responsivity to reward within the ventral striatum (e.g., nucleus accumbens) may drive sensation seeking behaviors, few studies have examined the neural mechanisms associated with stable individual differences in sensation seeking across development. To address this issue, the current study used functional magnetic resonance imaging to examine the association between neural responding to reward and stable patterns of sensation seeking across a three-year follow-up period among healthy adolescents and young adults (N = 139). Results indicated that during early adolescence (~ages 10-12), increased reactivity to reward within the nucleus accumbens (NAcc) was associated with lower levels of sensation seeking across a three-year follow-up. In middle adolescence (~ages 12-16), there was no evidence of a relationship between NAcc reactivity and sensation seeking. However, during the transition from late adolescence into adulthood (~ages 17-25), heightened reward-related reactivity in the NAcc was linked to increased sensation seeking. Findings suggest that the neural mechanisms underlying individual differences in trait-like levels of sensation seeking change from early to late adolescence.
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Affiliation(s)
- Samuel W Hawes
- Florida International University, Center for Children and Families, Department of Psychology, 11200 SW 8th Street, Miami, FL 33199, United States.
| | - Rajpreet Chahal
- University of California, Davis, Department of Psychology, 135 Young Hall, One Shields Avenue, Davis, CA 95616, United States
| | - Michael N Hallquist
- Pennsylvania State University, Department of Psychology, 140 Moore Building, University Park, PA 16801, United States
| | - David J Paulsen
- University of Pittsburgh, Department of Psychology, 121 Meyran Avenue, Pittsburgh, PA 15213, United States
| | - Charles F Geier
- Pennsylvania State University, Department of Psychology, 140 Moore Building, University Park, PA 16801, United States
| | - Beatriz Luna
- University of Pittsburgh, Department of Psychology, 121 Meyran Avenue, Pittsburgh, PA 15213, United States; University of Pittsburgh, Department of Psychiatry, 121 Meyran Avenue, Pittsburgh, PA 15213, United States
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62
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Preferential coding of eye/hand motor actions in the human ventral occipito-temporal cortex. Neuropsychologia 2016; 93:116-127. [DOI: 10.1016/j.neuropsychologia.2016.10.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 09/21/2016] [Accepted: 10/14/2016] [Indexed: 01/23/2023]
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63
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Webb TW, Igelström KM, Schurger A, Graziano MSA. Cortical networks involved in visual awareness independent of visual attention. Proc Natl Acad Sci U S A 2016; 113:13923-13928. [PMID: 27849616 PMCID: PMC5137756 DOI: 10.1073/pnas.1611505113] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
It is now well established that visual attention, as measured with standard spatial attention tasks, and visual awareness, as measured by report, can be dissociated. It is possible to attend to a stimulus with no reported awareness of the stimulus. We used a behavioral paradigm in which people were aware of a stimulus in one condition and unaware of it in another condition, but the stimulus drew a similar amount of spatial attention in both conditions. The paradigm allowed us to test for brain regions active in association with awareness independent of level of attention. Participants performed the task in an MRI scanner. We looked for brain regions that were more active in the aware than the unaware trials. The largest cluster of activity was obtained in the temporoparietal junction (TPJ) bilaterally. Local independent component analysis (ICA) revealed that this activity contained three distinct, but overlapping, components: a bilateral, anterior component; a left dorsal component; and a right dorsal component. These components had brain-wide functional connectivity that partially overlapped the ventral attention network and the frontoparietal control network. In contrast, no significant activity in association with awareness was found in the banks of the intraparietal sulcus, a region connected to the dorsal attention network and traditionally associated with attention control. These results show the importance of separating awareness and attention when testing for cortical substrates. They are also consistent with a recent proposal that awareness is associated with ventral attention areas, especially in the TPJ.
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Affiliation(s)
- Taylor W Webb
- Department of Psychology, Princeton University, Princeton, NJ 08544
| | | | - Aaron Schurger
- Cognitive Neuroimaging Unit, NeuroSpin Research Center, Commissariat a l'Energie Atomique (CEA)-Saclay, 91191 Gif-sur-Yvette, France
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64
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Cookson SL, Hazeltine E, Schumacher EH. Neural representation of stimulus-response associations during task preparation. Brain Res 2016; 1648:496-505. [PMID: 27527267 DOI: 10.1016/j.brainres.2016.08.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 07/19/2016] [Accepted: 08/11/2016] [Indexed: 10/21/2022]
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65
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Braem S, King JA, Korb FM, Krebs RM, Notebaert W, Egner T. The Role of Anterior Cingulate Cortex in the Affective Evaluation of Conflict. J Cogn Neurosci 2016; 29:137-149. [PMID: 27575278 DOI: 10.1162/jocn_a_01023] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
An influential theory of ACC function argues that this brain region plays a crucial role in the affective evaluation of performance monitoring and control demands. Specifically, control-demanding processes such as response conflict are thought to be registered as aversive signals by ACC, which in turn triggers processing adjustments to support avoidance learning. In support of conflict being treated as an aversive event, recent behavioral studies demonstrated that incongruent (i.e., conflict inducing), relative to congruent, stimuli can speed up subsequent negative, relative to positive, affective picture processing. Here, we used fMRI to investigate directly whether ACC activity in response to negative versus positive pictures is modulated by preceding control demands, consisting of conflict and task-switching conditions. The results show that negative, relative to positive, pictures elicited higher ACC activation after congruent, relative to incongruent, trials, suggesting that ACC's response to negative (positive) pictures was indeed affectively primed by incongruent (congruent) trials. Interestingly, this pattern of results was observed on task repetitions but disappeared on task alternations. This study supports the proposal that conflict induces negative affect and is the first to show that this affective signal is reflected in ACC activation.
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66
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Yu Z, Prado R, Quinlan EB, Cramer SC, Ombao H. Understanding the Impact of Stroke on Brain Motor Function: A Hierarchical Bayesian Approach. J Am Stat Assoc 2016; 111:549-563. [PMID: 28138206 DOI: 10.1080/01621459.2015.1133425] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Stroke is a disturbance in blood supply to the brain resulting in the loss of brain functions, particularly motor function. A study was conducted by the UCI Neurorehabilitation Lab to investigate the impact of stroke on motor-related brain regions. Functional MRI (fMRI) data were collected from stroke patients and healthy controls while the subjects performed a simple motor task. In addition to affecting local neuronal activation strength, stroke might also alter communications (i.e., connectivity) between brain regions. We develop a hierarchical Bayesian modeling approach for the analysis of multi-subject fMRI data that allows us to explore brain changes due to stroke. Our approach simultaneously estimates activation and condition-specific connectivity at the group level, and provides estimates for region/subject-specific hemodynamic response functions. Moreover, our model uses spike and slab priors to allow for direct posterior inference on the connectivity network. Our results indicate that motor-control regions show greater activation in the unaffected hemisphere and the midline surface in stroke patients than those same regions in healthy controls during the simple motor task. We also note increased connectivity within secondary motor regions in stroke subjects. These findings provide insight into altered neural correlates of movement in subjects who suffered a stroke.
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Affiliation(s)
- Zhe Yu
- Department of Statistics, University of California at Irvine
| | - Raquel Prado
- Department of Applied Mathematics & Statistics, University of California at Santa Cruz
| | - Erin B Quinlan
- Department of Anatomy & Neurobiology, University of California at Irvine
| | - Steven C Cramer
- Department of Neurobiology, University of California at Irvine
| | - Hernando Ombao
- Department of Statistics, University of California at Irvine
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67
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Anhedonia is associated with reduced incentive cue related activation in the basal ganglia. COGNITIVE AFFECTIVE & BEHAVIORAL NEUROSCIENCE 2016; 15:749-67. [PMID: 26105776 DOI: 10.3758/s13415-015-0366-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Research has shown that reward incentives improve cognitive control in motivationally salient situations. Much previous work in this domain has focused on incentive cue-related activity in a number of brain regions, including the dorsolateral prefrontal cortex (DLPFC) and striatum. However, the more sustained changes in functional brain activity during task contexts with incentives have been relatively less explored. Here, we examined both the cue-related and sustained effects of rewards (i.e., monetary incentives) on cognitive control, with a particular focus on the roles of the DLPFC and striatum, using a mixed state-item design. We investigated whether variability in a reward-related trait (i.e., anhedonia) would modulate the sustained and/or the cue-related transient aspects of motivated cognitive control. Twenty-seven healthy individuals performed a modified response conflict task (Padmala & Pessoa, Journal of Cognitive Neuroscience, 23, 3419-3432, 2011) during scanning, in which participants were asked to categorize images as either houses or buildings with either congruent or incongruent overlaid words. Participants performed a baseline condition without knowledge of monetary incentives, followed by reward blocks with monetary incentives on some cued trials (reward cues) for fast and correct responses. We replicated previous work by showing increases in both sustained activity during reward versus baseline blocks and transient. cue-related activity in bilateral DLPFC and the basal ganglia. Importantly, healthy individuals with higher anhedonia showed less of an increase in trial-by-trial activity as a function of reward in the lateral globus pallidus. Together, our results suggest that reduced hedonic experience may be related to abnormality of reward cue-related activity in the basal ganglia.
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Orchestrating Proactive and Reactive Mechanisms for Filtering Distracting Information: Brain-Behavior Relationships Revealed by a Mixed-Design fMRI Study. J Neurosci 2016; 36:988-1000. [PMID: 26791226 DOI: 10.1523/jneurosci.2966-15.2016] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Given the information overload often imparted to human cognitive-processing systems, suppression of irrelevant and distracting information is essential for successful behavior. Using a hybrid block/event-related fMRI design, we characterized proactive and reactive brain mechanisms for filtering distracting stimuli. Participants performed a flanker task, discriminating the direction of a target arrow in the presence versus absence of congruent or incongruent flanking distracting arrows during either Pure blocks (distracters always absent) or Mixed blocks (distracters on 80% of trials). Each Mixed block had either 20% or 60% incongruent trials. Activations in the dorsal frontoparietal attention network during Mixed versus Pure blocks evidenced proactive (blockwise) recruitment of a distraction-filtering mechanism. Sustained activations in right middle frontal gyrus during 60% Incongruent blocks correlated positively with behavioral indices of distraction-filtering (slowing when distracters might occur) and negatively with distraction-related behavioral costs (incongruent vs congruent trials), suggesting a role in coordinating proactive filtering of potential distracters. Event-related analyses showed that incongruent trials elicited greater reactive activations in 20% (vs 60%) Incongruent blocks for counteracting distraction and conflict, including in the insula and anterior cingulate. Context-related effects in occipitoparietal cortex consisted of greater target-evoked activations for distracter-absent trials (central-target-only) in Mixed versus Pure blocks, suggesting enhanced attentional engagement. Functional-localizer analyses in V1/V2/V3 revealed less distracter-processing activity in 60% (vs 20%) Incongruent blocks, presumably reflecting tonic suppression by proactive filtering mechanisms. These results delineate brain mechanisms underlying proactive and reactive filtering of distraction and conflict, and how they are orchestrated depending on distraction probability, thereby aiding task performance. Significance statement: Irrelevant stimuli distract people and impair their attentional performance. Here, we studied how the brain deals with distracting stimuli using a hybrid block/event-related fMRI design and a task that varied the probability of the occurrence of such distracting stimuli. The results suggest that when distraction is likely, a region in right frontal cortex proactively implements attentional control mechanisms to help filter out any distracting stimuli that might occur. In contrast, when distracting input occurs infrequently, this region is more reactively engaged to help limit the negative consequences of the distracters on behavioral performance. Our results thus help illuminate how the brain flexibly responds under differing attentional demands to engender effective behavior.
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Ellamil M, Fox KCR, Dixon ML, Pritchard S, Todd RM, Thompson E, Christoff K. Dynamics of neural recruitment surrounding the spontaneous arising of thoughts in experienced mindfulness practitioners. Neuroimage 2016; 136:186-96. [PMID: 27114056 DOI: 10.1016/j.neuroimage.2016.04.034] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 04/12/2016] [Accepted: 04/14/2016] [Indexed: 01/17/2023] Open
Abstract
Thoughts arise spontaneously in our minds with remarkable frequency, but tracking the brain systems associated with the early inception of a thought has proved challenging. Here we addressed this issue by taking advantage of the heightened introspective ability of experienced mindfulness practitioners to observe the onset of their spontaneously arising thoughts. We found subtle differences in timing among the many regions typically recruited by spontaneous thought. In some of these regions, fMRI signal peaked prior to the spontaneous arising of a thought - most notably in the medial temporal lobe and inferior parietal lobule. In contrast, activation in the medial prefrontal, temporopolar, mid-insular, lateral prefrontal, and dorsal anterior cingulate cortices peaked together with or immediately following the arising of spontaneous thought. We propose that brain regions that show antecedent recruitment may be preferentially involved in the initial inception of spontaneous thoughts, while those that show later recruitment may be preferentially involved in the subsequent elaboration and metacognitive processing of spontaneous thoughts. Our findings highlight the temporal dynamics of neural recruitment surrounding the emergence of spontaneous thoughts and may help account for some of spontaneous thought's peculiar qualities, including its wild diversity of content and its links to memory and attention.
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Affiliation(s)
- Melissa Ellamil
- Department of Psychology, University of British Columbia, 2136 West Mall, Vancouver, British Columbia V6T 1Z4, Canada
| | - Kieran C R Fox
- Department of Psychology, University of British Columbia, 2136 West Mall, Vancouver, British Columbia V6T 1Z4, Canada
| | - Matthew L Dixon
- Department of Psychology, University of British Columbia, 2136 West Mall, Vancouver, British Columbia V6T 1Z4, Canada
| | - Sean Pritchard
- School of Psychology, Fielding Graduate University, 2020 De la Vina Street, Santa Barbara, CA 93105, United States
| | - Rebecca M Todd
- Department of Psychology, University of British Columbia, 2136 West Mall, Vancouver, British Columbia V6T 1Z4, Canada; Centre for Brain Health, University of British Columbia, 2215 Wesbrook Mall, Vancouver, British Columbia V6T 1Z3, Canada
| | - Evan Thompson
- Department of Philosophy, University of British Columbia, 1866 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada
| | - Kalina Christoff
- Department of Psychology, University of British Columbia, 2136 West Mall, Vancouver, British Columbia V6T 1Z4, Canada; Centre for Brain Health, University of British Columbia, 2215 Wesbrook Mall, Vancouver, British Columbia V6T 1Z3, Canada.
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Culbreth AJ, Gold JM, Cools R, Barch DM. Impaired Activation in Cognitive Control Regions Predicts Reversal Learning in Schizophrenia. Schizophr Bull 2016; 42:484-93. [PMID: 26049083 PMCID: PMC4753588 DOI: 10.1093/schbul/sbv075] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Reinforcement learning deficits have been associated with schizophrenia (SZ). However, the pathophysiology that gives rise to these abnormalities remains unclear. To address this question, SZ patients (N = 58) and controls (CN; N = 36) completed a probabilistic reversal-learning paradigm during functional magnetic resonance imaging scanning. During the task, participants choose between 2 stimuli. Initially, 1 stimulus was frequently rewarded (80%); the other was infrequently rewarded (20%). The reward contingencies reversed periodically because the participant learned the more rewarded stimulus. The results indicated that SZ patients achieved fewer reversals than CN, and demonstrated decreased winstay-loseshift decision-making behavior. On loseshift compared to winstay trials, SZ patients showed reduced Blood Oxygen Level Dependent activation compared to CN in a network of brain regions widely associated with cognitive control, and striatal regions. Importantly, relationships between group membership and behavior were mediated by alterations in the activity of cognitive control regions, but not striatum. These findings indicate an important role for the cognitive control network in mediating the use and updating of value representations in SZ. Such results provide biological targets for further inquiry because researchers attempt to better characterize decision-making neural circuitry in SZ as a means to discover new pathways for interventions.
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Affiliation(s)
- Adam J Culbreth
- Department of Psychology, Washington University in St Louis, St Louis, MO;
| | - James M Gold
- University of Maryland School of Medicine, Department of Psychiatry and Maryland Psychiatric Research Center, Baltimore MD
| | - Roshan Cools
- Department of Psychiatry, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands; Centre for Cognitive Neuroimaging, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | - Deanna M Barch
- Department of Psychology, Washington University in St Louis, St Louis, MO; Department of Psychiatry & Radiology, Washington University in St Louis, St Louis, MO
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Astafiev SV, Zinn KL, Shulman GL, Corbetta M. Exploring the physiological correlates of chronic mild traumatic brain injury symptoms. NEUROIMAGE-CLINICAL 2016; 11:10-19. [PMID: 26909324 PMCID: PMC4732189 DOI: 10.1016/j.nicl.2016.01.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 12/31/2015] [Accepted: 01/04/2016] [Indexed: 12/14/2022]
Abstract
We report on the results of a multimodal imaging study involving behavioral assessments, evoked and resting-state BOLD fMRI, and DTI in chronic mTBI subjects. We found that larger task-evoked BOLD activity in the MT+/LO region in extra-striate visual cortex correlated with mTBI and PTSD symptoms, especially light sensitivity. Moreover, higher FA values near the left optic radiation (OR) were associated with both light sensitivity and higher BOLD activity in the MT+/LO region. The MT+/LO region was localized as a region of abnormal functional connectivity with central white matter regions previously found to have abnormal physiological signals during visual eye movement tracking (Astafiev et al., 2015). We conclude that mTBI symptoms and light sensitivity may be related to excessive responsiveness of visual cortex to sensory stimuli. This abnormal sensitivity may be related to chronic remodeling of white matter visual pathways acutely injured. We report a multimodal imaging study of symptoms in chronic mTBI. Higher BOLD activity in the MT +/LO region correlated with mTBI symptoms. Higher FA near the left optic radiation was associated with light sensitivity.
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Affiliation(s)
- Serguei V Astafiev
- Department of Neurology, Washington University in St. Louis, 660 S. Euclid Ave, Campus Box 8225, St. Louis, MO 63110, USA.
| | - Kristina L Zinn
- Department of Neurology, Washington University in St. Louis, 660 S. Euclid Ave, Campus Box 8225, St. Louis, MO 63110, USA.
| | - Gordon L Shulman
- Department of Neurology, Washington University in St. Louis, 660 S. Euclid Ave, Campus Box 8225, St. Louis, MO 63110, USA.
| | - Maurizio Corbetta
- Department of Neurology, Washington University in St. Louis, 660 S. Euclid Ave, Campus Box 8225, St. Louis, MO 63110, USA.
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Sumner JA, Sheridan MA, Drury SS, Esteves KC, Walsh K, Koenen KC, McLaughlin KA. Variation in CACNA1C is Associated with Amygdala Structure and Function in Adolescents. J Child Adolesc Psychopharmacol 2015; 25:701-10. [PMID: 26401721 PMCID: PMC4653820 DOI: 10.1089/cap.2015.0047] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Genome-wide association studies have identified allelic variation in CACNA1C as a risk factor for multiple psychiatric disorders associated with limbic system dysfunction, including bipolar disorder, schizophrenia, and depression. The CACNA1C gene codes for a subunit of L-type voltage-gated calcium channels, which modulate amygdala function. Although CACNA1C genotype appears to be associated with amygdala morphology and function in adults with and without psychopathology, whether genetic variation influences amygdala structure and function earlier in development has not been examined. METHODS In this first investigation of the neural correlates of CACNA1C in young individuals, we examined associations between two single nucleotide polymorphisms in CACNA1C (rs1006737 and rs4765914) with amygdala volume and activation during an emotional processing task in 58 adolescents and young adults 13-20 years of age. RESULTS Minor (T) allele carriers of rs4765914 exhibited smaller amygdala volume than major (C) allele homozygotes (β=-0.33, p=0.006). Furthermore, minor (A) allele homozygotes of rs1006737 exhibited increased blood-oxygen-level-dependent (BOLD) signal in the amygdala when viewing negative (vs. neutral) stimuli (β=0.29, p=0.040) and decreased BOLD signal in the amygdala when instructed to downregulate their emotional response to negative stimuli (β=-0.38, p=0.009). Follow-up analyses indicated that childhood trauma did not moderate the associations of CACNA1C variation with amygdala structure and function (ps>0.170). CONCLUSIONS Findings indicate that CACNA1C-related differences in amygdala structure and function are present by adolescence. However, population stratification is a concern, given the racial/ethnic heterogeneity of our sample, and our findings do not have direct clinical implications currently. Nevertheless, these results suggest that developmentally informed research can begin to shed light on the time course by which genetic liability may translate into neural differences associated with vulnerability to psychopathology.
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Affiliation(s)
- Jennifer A. Sumner
- Department of Epidemiology, Columbia University Mailman School of Public Health, New York, New York
| | - Margaret A. Sheridan
- Developmental Medicine Center, Boston Children's Hospital, Boston, Massachusetts.,Department of Pediatrics, Harvard Medical School, Boston, Massachusetts
| | - Stacy S. Drury
- Department of Psychiatry and Behavioral Sciences, Tulane University School of Medicine, New Orleans, Louisiana
| | - Kyle C. Esteves
- Department of Psychiatry and Behavioral Sciences, Tulane University School of Medicine, New Orleans, Louisiana
| | - Kate Walsh
- Department of Epidemiology, Columbia University Mailman School of Public Health, New York, New York
| | - Karestan C. Koenen
- Department of Epidemiology, Columbia University Mailman School of Public Health, New York, New York
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Lobben M, D'Ascenzo S. Grounding grammatical categories: attention bias in hand space influences grammatical congruency judgment of Chinese nominal classifiers. Front Psychol 2015; 6:1299. [PMID: 26379611 PMCID: PMC4550751 DOI: 10.3389/fpsyg.2015.01299] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Accepted: 08/13/2015] [Indexed: 11/28/2022] Open
Abstract
Embodied cognitive theories predict that linguistic conceptual representations are grounded and continually represented in real world, sensorimotor experiences. However, there is an on-going debate on whether this also holds for abstract concepts. Grammar is the archetype of abstract knowledge, and therefore constitutes a test case against embodied theories of language representation. Former studies have largely focussed on lexical-level embodied representations. In the present study we take the grounding-by-modality idea a step further by using reaction time (RT) data from the linguistic processing of nominal classifiers in Chinese. We take advantage of an independent body of research, which shows that attention in hand space is biased. Specifically, objects near the hand consistently yield shorter RTs as a function of readiness for action on graspable objects within reaching space, and the same biased attention inhibits attentional disengagement. We predicted that this attention bias would equally apply to the graspable object classifier but not to the big object classifier. Chinese speakers (N = 22) judged grammatical congruency of classifier-noun combinations in two conditions: graspable object classifier and big object classifier. We found that RTs for the graspable object classifier were significantly faster in congruent combinations, and significantly slower in incongruent combinations, than the big object classifier. There was no main effect on grammatical violations, but rather an interaction effect of classifier type. Thus, we demonstrate here grammatical category-specific effects pertaining to the semantic content and by extension the visual and tactile modality of acquisition underlying the acquisition of these categories. We conclude that abstract grammatical categories are subjected to the same mechanisms as general cognitive and neurophysiological processes and may therefore be grounded.
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Affiliation(s)
- Marit Lobben
- Department of Psychology, University of Oslo, Oslo Norway
| | - Stefania D'Ascenzo
- Department of Communication and Economics, University of Modena and Reggio Emilia, Emilia-Romagna Italy
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Brain-behavior relationships in the experience and regulation of negative emotion in healthy children: implications for risk for childhood depression. Dev Psychopathol 2015; 26:1289-303. [PMID: 25422962 DOI: 10.1017/s0954579414001035] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Structural and functional alterations in a variety of brain regions have been associated with depression and risk for depression across the life span. A majority of these regions are associated with emotion reactivity and/or regulation. However, it is generally unclear what mechanistic role these alterations play in the etiology of depression. A first step toward understanding this is to characterize the relationships between variation in brain structure/function and individual differences in depression severity and related processes, particularly emotion regulation. To this end, the current study examines how brain structure and function predict concurrent and longitudinal measures of depression symptomology and emotion regulation skills in psychiatrically healthy school-age children (N = 60). Specifically, we found that smaller hippocampus volumes and greater responses to sad faces in emotion reactivity regions predict increased depressive symptoms at the time of scan, whereas larger amygdala volumes, smaller insula volumes, and greater responses in emotion reactivity regions predict decreased emotion regulation skills. In addition, larger insula volumes predict improvements in emotion regulation skills even after accounting for emotion regulation at the time of scan. Understanding brain-behavior relationships in psychiatrically healthy samples, especially early in development, will help inform normative developmental trajectories and neural alterations in depression and other affective pathology.
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75
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Nelson SM, Savalia NK, Fishell AK, Gilmore AW, Zou F, Balota DA, McDermott KB. Default Mode Network Activity Predicts Early Memory Decline in Healthy Young Adults Aged 18–31. Cereb Cortex 2015. [DOI: 10.1093/cercor/bhv165] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
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Griffis JC, Elkhetali AS, Vaden RJ, Visscher KM. Distinct effects of trial-driven and task Set-related control in primary visual cortex. Neuroimage 2015; 120:285-297. [PMID: 26163806 DOI: 10.1016/j.neuroimage.2015.07.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2014] [Revised: 06/02/2015] [Accepted: 07/03/2015] [Indexed: 11/28/2022] Open
Abstract
Task sets are task-specific configurations of cognitive processes that facilitate task-appropriate reactions to stimuli. While it is established that the trial-by-trial deployment of visual attention to expected stimuli influences neural responses in primary visual cortex (V1) in a retinotopically specific manner, it is not clear whether the mechanisms that help maintain a task set over many trials also operate with similar retinotopic specificity. Here, we address this question by using BOLD fMRI to characterize how portions of V1 that are specialized for different eccentricities respond during distinct components of an attention-demanding discrimination task: cue-driven preparation for a trial, trial-driven processing, task-initiation at the beginning of a block of trials, and task-maintenance throughout a block of trials. Tasks required either unimodal attention to an auditory or a visual stimulus or selective intermodal attention to the visual or auditory component of simultaneously presented visual and auditory stimuli. We found that while the retinotopic patterns of trial-driven and cue-driven activity depended on the attended stimulus, the retinotopic patterns of task-initiation and task-maintenance activity did not. Further, only the retinotopic patterns of trial-driven activity were found to depend on the presence of inter-modal distraction. Participants who performed well on the intermodal selective attention tasks showed strong task-specific modulations of both trial-driven and task-maintenance activity. Importantly, task-related modulations of trial-driven and task-maintenance activity were in opposite directions. Together, these results confirm that there are (at least) two different processes for top-down control of V1: One, working trial-by-trial, differently modulates activity across different eccentricity sectors - portions of V1 corresponding to different visual eccentricities. The second process works across longer epochs of task performance, and does not differ among eccentricity sectors. These results are discussed in the context of previous literature examining top-down control of visual cortical areas.
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Affiliation(s)
- Joseph C Griffis
- The University of Alabama at Birmingham Department of Psychology
| | | | - Ryan J Vaden
- The University of Alabama at Birmingham Department of Neurobiology
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Chevrier A, Cheyne D, Graham S, Schachar R. Dissociating Two Stages of Preparation in the Stop Signal Task Using fMRI. PLoS One 2015; 10:e0130992. [PMID: 26110429 PMCID: PMC4481508 DOI: 10.1371/journal.pone.0130992] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 05/27/2015] [Indexed: 12/04/2022] Open
Abstract
Often we must balance being prepared to act quickly with being prepared to suddenly stop. The stop signal task (SST) is widely used to study inhibitory control, and provides a measure of the speed of the stop process that is robust to changes in subjects' response strategy. Previous studies have shown that preparation affects inhibition. We used fMRI to separate activity that occurs after a brief (500 ms) warning stimulus (warning-phase) from activity that occurs during responses that follow (response-phase). Both of these phases could contribute to the preparedness to stop because they both precede stop signals. Warning stimuli activated posterior networks that signal the need for top-down control, whereas response phases engaged prefrontal and subcortical networks that implement top-down control. Regression analyses revealed that both of these phases affect inhibitory control in different ways. Warning-phase activity in the cerebellum and posterior cingulate predicted stop latency and accuracy, respectively. By contrast, response-phase activity in fronto-temporal areas and left striatum predicted go speed and stop accuracy, in pre-supplementary motor area affected stop accuracy, and in right striatum predicted stop latency and accuracy. The ability to separate hidden contributions to inhibitory control during warning-phases from those during response-phases can aid in the study of models of preparation and inhibitory control, and of disorders marked by poor top-down control.
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Affiliation(s)
- Andre Chevrier
- University of Toronto, Institute of Medical Science. Toronto, Ontario, Canada
| | - Douglas Cheyne
- University of Toronto, Institute of Biomaterials and Biomedical EngineeringDepartment of Medical Imaging, Toronto, Ontario, Canada
| | - Simon Graham
- Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
| | - Russell Schachar
- The Hospital for Sick Children, Psychiatry research, Toronto, Ontario Canada
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Lebois LAM, Papies EK, Gopinath K, Cabanban R, Quigley KS, Krishnamurthy V, Barrett LF, Barsalou LW. A shift in perspective: Decentering through mindful attention to imagined stressful events. Neuropsychologia 2015; 75:505-24. [PMID: 26111487 DOI: 10.1016/j.neuropsychologia.2015.05.030] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Revised: 05/19/2015] [Accepted: 05/28/2015] [Indexed: 01/17/2023]
Abstract
Ruminative thoughts about a stressful event can seem subjectively real, as if the imagined event were happening in the moment. One possibility is that this subjective realism results from simulating the self as engaged in the stressful event (immersion). If so, then the process of decentering--disengaging the self from the event--should reduce the subjective realism associated with immersion, and therefore perceived stressfulness. To assess this account of decentering, we taught non-meditators a strategy for disengaging from imagined events, simply viewing these events as transient mental states (mindful attention). In a subsequent neuroimaging session, participants imagined stressful and non-stressful events, while either immersing themselves or adopting mindful attention. In conjunction analyses, mindful attention down-regulated the processing of stressful events relative to baseline, whereas immersion up-regulated their processing. In direct contrasts between mindful attention and immersion, mindful attention showed greater activity in brain areas associated with perspective shifting and effortful attention, whereas immersion showed greater activity in areas associated with self-processing and visceral states. These results suggest that mindful attention produces decentering by disengaging embodied senses of self from imagined situations so that affect does not develop.
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Affiliation(s)
- Lauren A M Lebois
- Department of Psychology, Emory University, United States; McLean Hospital/Harvard Medical School, MA, United States.
| | - Esther K Papies
- Department of Social and Organizational Psychology, Utrecht University, The Netherlands
| | - Kaundinya Gopinath
- Department of Radiology and Imaging Sciences, United States; Center for Systems Imaging, Emory School of Medicine, United States
| | - Romeo Cabanban
- Center for Systems Imaging, Emory School of Medicine, United States
| | - Karen S Quigley
- Department of Psychology, Northeastern University, United States; Edith Nourse Rogers Memorial (Bedford) VA Hospital, United States
| | - Venkatagiri Krishnamurthy
- Department of Radiology and Imaging Sciences, United States; Center for Systems Imaging, Emory School of Medicine, United States
| | - Lisa Feldman Barrett
- Department of Psychology, Northeastern University, United States; Massachusetts General Hospital/Harvard Medical School, United States
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Abstract
We continuously encounter and process novel events in the surrounding world, but only some episodes will leave detailed memory traces that can be recollected after weeks and months. Here, our aim was to monitor brain activity during encoding of events that eventually transforms into long-term stable memories. Previous functional magnetic resonance imaging (fMRI) studies have shown that the degree of activation of different brain regions during encoding is predictive of later recollection success. However, most of these studies tested participants' memories the same day as encoding occurred, whereas several lines of research suggest that extended post-encoding processing is of crucial importance for long-term consolidation. Using fMRI, we tested whether the same encoding mechanisms are predictive of recollection success after hours as after a retention interval of several weeks. Seventy-eight participants were scanned during an associative encoding task and given a source memory test the same day or after ∼6 weeks. We found a strong link between regional activity levels during encoding and recollection success over short time intervals. However, results further showed that durable source memories, i.e., events recollected after several weeks, were not simply the events associated with the highest activity levels at encoding. Rather, strong levels of connectivity between the right hippocampus and perceptual areas, as well as with parts of the self-referential default-mode network, seemed instrumental in establishing durable source memories. Thus, we argue that an initial intensity-based encoding is necessary for short-term encoding of events, whereas additional processes involving hippocampal-cortical communication aid transformation into stable long-term memories.
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Regional brain activation supporting cognitive control in the context of reward is associated with treated adolescents' marijuana problem severity at follow-up: A preliminary study. Dev Cogn Neurosci 2015; 16:93-100. [PMID: 26026506 PMCID: PMC4644722 DOI: 10.1016/j.dcn.2015.05.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 05/05/2015] [Accepted: 05/07/2015] [Indexed: 11/29/2022] Open
Abstract
Activation during rewarded antisaccade task correlated with later marijuana severity. Antisaccade behavioral performance was not associated with treatment outcome. Preliminary results suggest a brain-based correlate of treatment outcome in youth.
This preliminary study examined the extent to which regional brain activation during a reward cue antisaccade (AS) task was associated with 6-month treatment outcome in adolescent substance users. Antisaccade performance provides a sensitive measure of executive function and cognitive control, and generally improves with reward cues. We hypothesized that when preparing to execute an AS, greater activation in regions associated with cognitive and oculomotor control supporting AS, particularly during reward cue trials, would be associated with lower substance use severity at 6-month follow-up. Adolescents (n = 14, ages 14–18) recruited from community-based outpatient treatment completed an fMRI reward cue AS task (reward and neutral conditions), and provided follow-up data. Results indicated that AS errors decreased in reward, compared to neutral, trials. AS behavioral performance, however, was not associated with treatment outcome. As hypothesized, activation in regions of interest (ROIs) associated with cognitive (e.g., ventrolateral prefrontal cortex) and oculomotor control (e.g., supplementary eye field) during reward trials were inversely correlated with marijuana problem severity at 6-months. ROI activation during neutral trials was not associated with outcomes. Results support the role of motivational (reward cue) factors to enhance cognitive control processes, and suggest a potential brain-based correlate of youth treatment outcome.
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81
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Kharitonova M, Winter W, Sheridan MA. As Working Memory Grows: A Developmental Account of Neural Bases of Working Memory Capacity in 5- to 8-Year Old Children and Adults. J Cogn Neurosci 2015; 27:1775-88. [PMID: 25961641 DOI: 10.1162/jocn_a_00824] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Working memory develops slowly: Even by age 8, children are able to maintain only half the number of items that adults can remember. Neural substrates that support performance on working memory tasks also have a slow developmental trajectory and typically activate to a lesser extent in children, relative to adults. Little is known about why younger participants elicit less neural activation. This may be due to maturational differences, differences in behavioral performance, or both. Here we investigate the neural correlates of working memory capacity in children (ages 5-8) and adults using a visual working memory task with parametrically increasing loads (from one to four items) using fMRI. This task allowed us to estimate working memory capacity limit for each group. We found that both age groups increased the activation of frontoparietal networks with increasing working memory loads, until working memory capacity was reached. Because children's working memory capacity limit was half of that for adults, the plateau occurred at lower loads for children. Had a parametric increase in load not been used, this would have given an impression of less activation overall and less load-dependent activation for children relative to adults. Our findings suggest that young children and adults recruit similar frontoparietal networks at working memory loads that do not exceed capacity and highlight the need to consider behavioral performance differences when interpreting developmental differences in neural activation.
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Affiliation(s)
- Maria Kharitonova
- Boston Children's Hospital/Harvard Medical School.,Northwestern University
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82
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Astafiev SV, Shulman GL, Metcalf NV, Rengachary J, MacDonald CL, Harrington DL, Maruta J, Shimony JS, Ghajar J, Diwakar M, Huang MX, Lee RR, Corbetta M. Abnormal White Matter Blood-Oxygen-Level-Dependent Signals in Chronic Mild Traumatic Brain Injury. J Neurotrauma 2015; 32:1254-71. [PMID: 25758167 DOI: 10.1089/neu.2014.3547] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Concussion, or mild traumatic brain injury (mTBI), can cause persistent behavioral symptoms and cognitive impairment, but it is unclear if this condition is associated with detectable structural or functional brain changes. At two sites, chronic mTBI human subjects with persistent post-concussive symptoms (three months to five years after injury) and age- and education-matched healthy human control subjects underwent extensive neuropsychological and visual tracking eye movement tests. At one site, patients and controls also performed the visual tracking tasks while blood-oxygen-level-dependent (BOLD) signals were measured with functional magnetic resonance imaging. Although neither neuropsychological nor visual tracking measures distinguished patients from controls at the level of individual subjects, abnormal BOLD signals were reliably detected in patients. The most consistent changes were localized in white matter regions: anterior internal capsule and superior longitudinal fasciculus. In contrast, BOLD signals were normal in cortical regions, such as the frontal eye field and intraparietal sulcus, that mediate oculomotor and attention functions necessary for visual tracking. The abnormal BOLD signals accurately differentiated chronic mTBI patients from healthy controls at the single-subject level, although they did not correlate with symptoms or neuropsychological performance. We conclude that subjects with persistent post-concussive symptoms can be identified years after their TBI using fMRI and an eye movement task despite showing normal structural MRI and DTI.
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Affiliation(s)
- Serguei V Astafiev
- 1 Department of Neurology, Washington University in St. Louis , St. Louis, Missouri
| | - Gordon L Shulman
- 1 Department of Neurology, Washington University in St. Louis , St. Louis, Missouri
| | - Nicholas V Metcalf
- 1 Department of Neurology, Washington University in St. Louis , St. Louis, Missouri
| | - Jennifer Rengachary
- 1 Department of Neurology, Washington University in St. Louis , St. Louis, Missouri
| | | | - Deborah L Harrington
- 2 Department of Radiology, University of California , San Diego, San Diego, California
| | - Jun Maruta
- 3 Brain Trauma Foundation , New York, New York
| | | | - Jamshid Ghajar
- 3 Brain Trauma Foundation , New York, New York.,4 Department of Neurological Surgery, Weill Cornell Medical College , New York, New York
| | - Mithun Diwakar
- 2 Department of Radiology, University of California , San Diego, San Diego, California
| | - Ming-Xiong Huang
- 2 Department of Radiology, University of California , San Diego, San Diego, California
| | - Roland R Lee
- 2 Department of Radiology, University of California , San Diego, San Diego, California
| | - Maurizio Corbetta
- 1 Department of Neurology, Washington University in St. Louis , St. Louis, Missouri
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83
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Wang Y, Quadflieg S. In our own image? Emotional and neural processing differences when observing human-human vs human-robot interactions. Soc Cogn Affect Neurosci 2015; 10:1515-24. [PMID: 25911418 PMCID: PMC4631149 DOI: 10.1093/scan/nsv043] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 04/14/2015] [Indexed: 11/13/2022] Open
Abstract
Notwithstanding the significant role that human-robot interactions (HRI) will play in the near future, limited research has explored the neural correlates of feeling eerie in response to social robots. To address this empirical lacuna, the current investigation examined brain activity using functional magnetic resonance imaging while a group of participants (n = 26) viewed a series of human-human interactions (HHI) and HRI. Although brain sites constituting the mentalizing network were found to respond to both types of interactions, systematic neural variation across sites signaled diverging social-cognitive strategies during HHI and HRI processing. Specifically, HHI elicited increased activity in the left temporal-parietal junction indicative of situation-specific mental state attributions, whereas HRI recruited the precuneus and the ventromedial prefrontal cortex (VMPFC) suggestive of script-based social reasoning. Activity in the VMPFC also tracked feelings of eeriness towards HRI in a parametric manner, revealing a potential neural correlate for a phenomenon known as the uncanny valley. By demonstrating how understanding social interactions depends on the kind of agents involved, this study highlights pivotal sub-routes of impression formation and identifies prominent challenges in the use of humanoid robots.
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Affiliation(s)
- Yin Wang
- Division of Psychology, New York University
- Abu Dhabi, Abu Dhabi, UAE
| | - Susanne Quadflieg
- Division of Psychology, New York University
- Abu Dhabi, Abu Dhabi, UAE
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84
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Effects of intranasal oxytocin on thermal pain in healthy men: a randomized functional magnetic resonance imaging study. Psychosom Med 2015; 77:156-66. [PMID: 25647754 DOI: 10.1097/psy.0000000000000142] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
OBJECTIVE Intranasal oxytocin has been shown to affect human social and emotional processing, but its potential to affect pain remains elusive. This randomized, placebo-controlled, double-blind, crossover trial investigated the effect of intranasal oxytocin on the perception and processing of noxious experimental heat in 36 healthy male volunteers. METHODS Thermal thresholds were determined according to the Quantitative Sensory Testing protocol. A functional magnetic resonance imaging experiment including intensity and unpleasantness ratings of tonic heat was used to investigate the effects of oxytocin within the brain. RESULTS Thirty men (aged 18-50 years) were included in the study. Intranasal oxytocin had no significant effect on thermal thresholds, but significantly (t = -2.06, p = .046) reduced heat intensity ratings during functional magnetic resonance imaging. The effect on intensity ratings was small (-3.46 points on a 100-point visual analog scale [95% confidence interval {CI} = -6.86 to -0.07] and independent of temperature. No effects of oxytocin on stimulus- or temperature-related processing were found at the whole-brain level at a robust statistical threshold. A region of interest analysis indicated that oxytocin caused small but significant decreases in left (-0.045%, 95% CI = -0.087 to -0.003, t = -2.19, p = .037) and right (-0.051%, 95% CI = -0.088 to -0.014], t = -2.82, p = .008) amygdala activity across all temperatures. CONCLUSIONS The present study provides evidence for a significant but subtle inhibitory effect of oxytocin on thermal stimulus ratings and concurrent amygdala activity. Neither of the two effects significantly depended of temperature; therefore, the hypothesis of a pain-specific effect of oxytocin could not be confirmed. TRIAL REGISTRATION EUDRA-CT 2009-015115-40.
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85
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Kasper RW, Grafton ST, Eckstein MP, Giesbrecht B. Multimodal neuroimaging evidence linking memory and attention systems during visual search cued by context. Ann N Y Acad Sci 2015; 1339:176-89. [DOI: 10.1111/nyas.12640] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Ryan W. Kasper
- Department of Psychological and Brain Sciences; Institute for Collaborative Biotechnologies, University of California, Santa Barbara; Santa Barbara California
| | - Scott T. Grafton
- Department of Psychological and Brain Sciences; Institute for Collaborative Biotechnologies, University of California, Santa Barbara; Santa Barbara California
| | - Miguel P. Eckstein
- Department of Psychological and Brain Sciences; Institute for Collaborative Biotechnologies, University of California, Santa Barbara; Santa Barbara California
| | - Barry Giesbrecht
- Department of Psychological and Brain Sciences; Institute for Collaborative Biotechnologies, University of California, Santa Barbara; Santa Barbara California
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86
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Wilson-Mendenhall CD, Barrett LF, Barsalou LW. Variety in emotional life: within-category typicality of emotional experiences is associated with neural activity in large-scale brain networks. Soc Cogn Affect Neurosci 2015; 10:62-71. [PMID: 24563528 PMCID: PMC4994840 DOI: 10.1093/scan/nsu037] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Revised: 02/19/2014] [Accepted: 02/19/2014] [Indexed: 11/14/2022] Open
Abstract
The tremendous variability within categories of human emotional experience receives little empirical attention. We hypothesized that atypical instances of emotion categories (e.g. pleasant fear of thrill-seeking) would be processed less efficiently than typical instances of emotion categories (e.g. unpleasant fear of violent threat) in large-scale brain networks. During a novel fMRI paradigm, participants immersed themselves in scenarios designed to induce atypical and typical experiences of fear, sadness or happiness (scenario immersion), and then focused on and rated the pleasant or unpleasant feeling that emerged (valence focus) in most trials. As predicted, reliably greater activity in the 'default mode' network (including medial prefrontal cortex and posterior cingulate) was observed for atypical (vs typical) emotional experiences during scenario immersion, suggesting atypical instances require greater conceptual processing to situate the socio-emotional experience. During valence focus, reliably greater activity was observed for atypical (vs typical) emotional experiences in the 'salience' network (including anterior insula and anterior cingulate), suggesting atypical instances place greater demands on integrating shifting body signals with the sensory and social context. Consistent with emerging psychological construction approaches to emotion, these findings demonstrate that is it important to study the variability within common categories of emotional experience.
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Affiliation(s)
- Christine D Wilson-Mendenhall
- Department of Psychology, Northeastern University, 125 Nightingale Hall, Boston, MA 02115 and Department of Psychology, Emory University, 483 Psychology and Interdisciplinary Sciences Building, 36 Eagle Row, Atlanta, GA 30322, USA
| | - Lisa Feldman Barrett
- Department of Psychology, Northeastern University, 125 Nightingale Hall, Boston, MA 02115 and Department of Psychology, Emory University, 483 Psychology and Interdisciplinary Sciences Building, 36 Eagle Row, Atlanta, GA 30322, USA
| | - Lawrence W Barsalou
- Department of Psychology, Northeastern University, 125 Nightingale Hall, Boston, MA 02115 and Department of Psychology, Emory University, 483 Psychology and Interdisciplinary Sciences Building, 36 Eagle Row, Atlanta, GA 30322, USA
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87
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Yang H, Susilo T, Duchaine B. The Anterior Temporal Face Area Contains Invariant Representations of Face Identity That Can Persist Despite the Loss of Right FFA and OFA. Cereb Cortex 2014; 26:1096-1107. [DOI: 10.1093/cercor/bhu289] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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88
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Elkhetali AS, Vaden RJ, Pool SM, Visscher KM. Early visual cortex reflects initiation and maintenance of task set. Neuroimage 2014; 107:277-288. [PMID: 25485712 DOI: 10.1016/j.neuroimage.2014.11.061] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 10/20/2014] [Accepted: 11/30/2014] [Indexed: 10/24/2022] Open
Abstract
The human brain is able to process information flexibly, depending on a person's task. The mechanisms underlying this ability to initiate and maintain a task set are not well understood, but they are important for understanding the flexibility of human behavior and developing therapies for disorders involving attention. Here we investigate the differential roles of early visual cortical areas in initiating and maintaining a task set. Using functional Magnetic Resonance Imaging (fMRI), we characterized three different components of task set-related, but trial-independent activity in retinotopically mapped areas of early visual cortex, while human participants performed attention demanding visual or auditory tasks. These trial-independent effects reflected: (1) maintenance of attention over a long duration, (2) orienting to a cue, and (3) initiation of a task set. Participants performed tasks that differed in the modality of stimulus to be attended (auditory or visual) and in whether there was a simultaneous distractor (auditory only, visual only, or simultaneous auditory and visual). We found that patterns of trial-independent activity in early visual areas (V1, V2, V3, hV4) depend on attended modality, but not on stimuli. Further, different early visual areas play distinct roles in the initiation of a task set. In addition, activity associated with maintaining a task set tracks with a participant's behavior. These results show that trial-independent activity in early visual cortex reflects initiation and maintenance of a person's task set.
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Affiliation(s)
- Abdurahman S Elkhetali
- Neurobiology Department, University of Alabama at Birmingham, CIRC 111D, 1530 3(RD) Avenue South, Birmingham, AL 35294, USA.
| | - Ryan J Vaden
- Neurobiology Department, University of Alabama at Birmingham, CIRC 111D, 1530 3(RD) Avenue South, Birmingham, AL 35294, USA.
| | - Sean M Pool
- Biomedical Engineering, University of Alabama at Birmingham, 1530 3(RD) Avenue South, Birmingham, AL 35294, USA.
| | - Kristina M Visscher
- Neurobiology Department, University of Alabama at Birmingham, CIRC 111D, 1530 3(RD) Avenue South, Birmingham, AL 35294, USA; Biomedical Engineering, University of Alabama at Birmingham, 1530 3(RD) Avenue South, Birmingham, AL 35294, USA; Psychology Department, University of Alabama at Birmingham, 1530 3(RD) Avenue South, Birmingham, AL 35294, USA.
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89
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Padmanabhan A, Garver K, O'Hearn K, Nawarawong N, Liu R, Minshew N, Sweeney J, Luna B. Developmental changes in brain function underlying inhibitory control in autism spectrum disorders. Autism Res 2014; 8:123-35. [PMID: 25382787 DOI: 10.1002/aur.1398] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Accepted: 05/28/2014] [Indexed: 11/06/2022]
Abstract
The development of inhibitory control-the ability to suppress inappropriate actions in order to make goal-directed responses-is often impaired in autism spectrum disorders (ASD). In the present study, we examined whether the impairments in inhibitory control evident in ASD reflect-in part-differences in the development of the neural substrates of inhibitory control from adolescence into adulthood. We conducted a functional magnetic resonance imaging (fMRI) study on the anti-saccade task, a probe of inhibitory control, in high-functioning adolescents and adults with ASD compared to a matched group of typically developing (TD) individuals. The ASD group did not show the age-related improvements in behavioral performance from adolescence to adulthood evident in the typical group, consistent with previous behavioral work. The fMRI results indicated that much of the circuitry recruited by the ASD group was similar to the TD group. However, the ASD group demonstrated some unique patterns, including: (a) a failure to recruit the frontal eye field during response preparation in adolescence but comparable recruitment in adulthood; (b) greater recruitment of putamen in adolescence and precuneus in adolescence and adulthood than the TD group; and (c) decreased recruitment in the inferior parietal lobule relative to TD groups. Taken together, these results suggest that brain circuitry underlying inhibitory control develops differently from adolescence to adulthood in ASD. Specifically, there may be relative underdevelopment of brain processes underlying inhibitory control in ASD, which may lead to engagement of subcortical compensatory processes.
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90
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Kalus S, Bothmann L, Yassouridis C, Czisch M, Sämann PG, Fahrmeir L. Statistical modeling of time-dependent fMRI activation effects. Hum Brain Mapp 2014; 36:731-43. [PMID: 25339617 DOI: 10.1002/hbm.22660] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Revised: 09/17/2014] [Accepted: 10/06/2014] [Indexed: 11/07/2022] Open
Abstract
Functional magnetic resonance imaging (fMRI) activation detection within stimulus-based experimental paradigms is conventionally based on the assumption that activation effects remain constant over time. This assumption neglects the fact that the strength of activation may vary, for example, due to habituation processes or changing attention. Neither the functional form of time variation can be retrieved nor short-lasting effects can be detected by conventional methods. In this work, a new dynamic approach is proposed that allows to estimate time-varying effect profiles and hemodynamic response functions in event-related fMRI paradigms. To this end, we incorporate the time-varying coefficient methodology into the fMRI general regression framework. Inference is based on a voxelwise penalized least squares procedure. We assess the strength of activation and corresponding time variation on the basis of pointwise confidence intervals on a voxel level. Additionally, spatial clusters of effect curves are presented. Results of the analysis of an active oddball experiment show that activation effects deviating from a constant trend coexist with time-varying effects that exhibit different types of shapes, such as linear, (inversely) U-shaped or fluctuating forms. In a comparison to conventional approaches, like classical SPM, we observe that time-constant methods are rather insensitive to detect temporary effects, because these do not emerge when aggregated across the entire experiment. Hence, it is recommended to base activation detection analyses not merely on time-constant procedures but to include flexible time-varying effects that harbour valuable information on individual response patterns.
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Affiliation(s)
- Stefanie Kalus
- Department of Statistics, Ludwig-Maximilians-University, Ludwigstr. 33, 80539, Munich, Germany
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91
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Wheeler ME, Woo SG, Ansel T, Tremel JJ, Collier AL, Velanova K, Ploran EJ, Yang T. The strength of gradually accruing probabilistic evidence modulates brain activity during a categorical decision. J Cogn Neurosci 2014; 27:705-19. [PMID: 25313658 DOI: 10.1162/jocn_a_00739] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The evolution of neural activity during a perceptual decision is well characterized by the evidence parameter in sequential sampling models. However, it is not known whether accumulating signals in human neuroimaging are related to the integration of evidence. Our aim was to determine whether activity accumulates in a nonperceptual task by identifying brain regions tracking the strength of probabilistic evidence. fMRI was used to measure whole-brain activity as choices were informed by integrating a series of learned prior probabilities. Participants first learned the predictive relationship between a set of shape stimuli and one of two choices. During scanned testing, they made binary choices informed by the sum of the predictive strengths of individual shapes. Sequences of shapes adhered to three distinct rates of evidence (RoEs): rapid, gradual, and switch. We predicted that activity in regions informing the decision would modulate as a function of RoE prior to the choice. Activity in some regions, including premotor areas, changed as a function of RoE and response hand, indicating a role in forming an intention to respond. Regions in occipital, temporal, and parietal lobes modulated as a function of RoE only, suggesting a preresponse stage of evidence processing. In all of these regions, activity was greatest on rapid trials and least on switch trials, which is consistent with an accumulation-to-boundary account. In contrast, activity in a set of frontal and parietal regions was greatest on switch and least on rapid trials, which is consistent with an effort or time-on-task account.
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92
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Neta M, Schlaggar BL, Petersen SE. Separable responses to error, ambiguity, and reaction time in cingulo-opercular task control regions. Neuroimage 2014; 99:59-68. [PMID: 24887509 PMCID: PMC4148211 DOI: 10.1016/j.neuroimage.2014.05.053] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 05/13/2014] [Accepted: 05/16/2014] [Indexed: 11/16/2022] Open
Abstract
The dorsal anterior cingulate (dACC), along with the closely affiliated anterior insula/frontal operculum, have been demonstrated to show three types of task control signals across a wide variety of tasks. One of these signals, a transient signal that is thought to represent performance feedback, shows greater activity to error than correct trials. Other work has found similar effects for uncertainty/ambiguity or conflict, though some argue that dACC activity is, instead, modulated primarily by other processes more reflected in reaction time. Here, we demonstrate that, rather than a single explanation, multiple information processing operations are crucial to characterizing the function of these brain regions, by comparing operations within a single paradigm. Participants performed two tasks in an fMRI experimental session: (1) deciding whether or not visually presented word pairs rhyme, and (2) rating auditorily presented single words as abstract or concrete. A pilot was used to identify ambiguous stimuli for both tasks (e.g., word pair: BASS/GRACE; single word: CHANGE). We found greater cingulo-opercular activity for errors and ambiguous trials than clear/correct trials, with a robust effect of reaction time. The effects of error and ambiguity remained when reaction time was regressed out, although the differences decreased. Further stepwise regression of response consensus (agreement across participants for each stimulus; a proxy for ambiguity) decreased differences between ambiguous and clear trials, but left error-related differences almost completely intact. These observations suggest that trial-wise responses in cingulo-opercular regions monitor multiple performance indices, including accuracy, ambiguity, and reaction time.
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Affiliation(s)
- Maital Neta
- Department of Neurology, Washington University School of Medicine, USA.
| | - Bradley L Schlaggar
- Department of Neurology, Washington University School of Medicine, USA; Department of Radiology, Washington University School of Medicine, USA; Department of Pediatrics, Washington University School of Medicine, USA; Department of Anatomy & Neurobiology, Washington University School of Medicine, USA
| | - Steven E Petersen
- Department of Neurology, Washington University School of Medicine, USA; Department of Radiology, Washington University School of Medicine, USA; Department of Anatomy & Neurobiology, Washington University School of Medicine, USA; Department of Neurosurgery, Washington University School of Medicine, USA; Department of Psychology, Washington University, St. Louis, MO, USA; Department of Biomedical Engineering, Washington University, St. Louis, MO, USA
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93
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Gilmore AW, Nelson SM, McDermott KB. The Contextual Association Network Activates More for Remembered than for Imagined Events. Cereb Cortex 2014; 26:611-7. [PMID: 25260708 DOI: 10.1093/cercor/bhu223] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The human capacities to remember events from the past and imagine events in the future rely on highly overlapping neural substrates. Neuroimaging studies have revealed brain regions that are more active for imagined events than remembered events, but the reverse pattern has not been shown consistently. Given that remembered events tend to be associated with more contextual information ( Johnson et al. 1988), one might expect a set of regions to demonstrate greater activity for remembered events. Specifically, regions sensitive to the strength of contextual associations might be hypothesized to show greater activity for remembered events. The present experiment tests this hypothesis. fMRI was used to identify brain regions within the contextual association network ( Bar and Aminoff 2003); regions within this network were then examined to see whether they showed differential activity during remembering and imagining. Bilateral regions within the parahippocampal cortex and retrosplenial complex responded more strongly to remembered past events, supporting work that suggests these events have more contextual information associated with them. Follow-up voxel-wise analysis demonstrated the specificity of these results, as did re-analysis of previous experimental datasets. These results suggest that a key differentiating feature of remembering and imagining is the strength of contextual associations.
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Affiliation(s)
- Adrian W Gilmore
- Department of Psychology, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Steven M Nelson
- Department of Psychology, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Kathleen B McDermott
- Department of Psychology, Washington University in St. Louis, St. Louis, MO 63130, USA Department of Radiology, Washington University in St. Louis, St. Louis, MO 63110, USA
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94
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Paulsen DJ, Hallquist MN, Geier CF, Luna B. Effects of incentives, age, and behavior on brain activation during inhibitory control: a longitudinal fMRI study. Dev Cogn Neurosci 2014; 11:105-15. [PMID: 25284272 PMCID: PMC4323861 DOI: 10.1016/j.dcn.2014.09.003] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Revised: 08/14/2014] [Accepted: 09/07/2014] [Indexed: 11/16/2022] Open
Abstract
Reward-modulated cognitive control is supported by amygdalar incentive processing. NAcc activation supports inhibitory control in youths. NAcc activation hinders inhibitory control in adults.
We investigated changes in brain function supporting inhibitory control under age-controlled incentivized conditions, separating age- and performance-related activation in an accelerated longitudinal design including 10- to 22-year-olds. Better inhibitory control correlated with striatal activation during neutral trials, while Age X Behavior interactions in the striatum indicated that in the absence of extrinsic incentives, younger subjects with greater reward circuitry activation successfully engage in greater inhibitory control. Age was negatively correlated with ventral amygdala activation during Loss trials, suggesting that amygdala function more strongly mediates bottom-up processing earlier in development when controlling the negative aspects of incentives to support inhibitory control. Together, these results indicate that with development, reward-modulated cognitive control may be supported by incentive processing transitions in the amygdala, and from facilitative to obstructive striatal function during inhibitory control.
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Affiliation(s)
- David J Paulsen
- Department of Psychiatry, University of Pittsburgh, United States.
| | | | - Charles F Geier
- Department of Human Development and Family Studies, Pennsylvania State University, United States
| | - Beatriz Luna
- Department of Psychiatry, University of Pittsburgh, United States; Department of Psychology, University of Pittsburgh, United States
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95
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Bhaijiwala M, Chevrier A, Schachar R. Withholding and canceling a response in ADHD adolescents. Brain Behav 2014; 4:602-14. [PMID: 25328838 PMCID: PMC4086366 DOI: 10.1002/brb3.244] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 05/27/2014] [Accepted: 06/01/2014] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Deficient response inhibition in situations involving a trade-off between response execution and response stopping is a hallmark of attention deficit hyperactive disorder (ADHD). There are two key components of response inhibition; reactive inhibition where one attempts to cancel an ongoing response and prospective inhibition is when one withholds a response pending a signal to stop. Prospective inhibition comes into play prior to the presentation of the stop signal and reactive inhibition follows the presentation of a signal to stop a particular action. The aim of this study is to investigate the neural activity evoked by prospective and reactive inhibition in adolescents with and without ADHD. METHODS Twelve adolescents with ADHD and 12 age-matched healthy controls (age range 9-18) were imaged while performing the stop signal task (SST). RESULTS Reactive inhibition activated right inferior frontal gyrus (IFG) in both groups. ADHD subjects activated IFG bilaterally. In controls, prospective inhibition invoked preactivation of the same part of right IFG that activated during reactive inhibition. In ADHD subjects, prospective inhibition was associated with deactivation in this region. Controls also deactivated the medial prefrontal cortex (MPFC) during prospective inhibition, whereas ADHD subjects activated the same area. DISCUSSION This pattern of activity changes in the same structures, but in opposite directions, was also evident across all phases of the task in various task-specific areas like the superior and middle temporal gyrus and other frontal areas. CONCLUSION Differences between ADHD and control participants in task-specific and default mode structures (IFG and MPFC) were evident during prospective, but not during reactive inhibition.
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Affiliation(s)
- Mehereen Bhaijiwala
- Institute of Medical Science, University of Toronto 7213 Medical Sciences Building, 1 King's College Circle, Toronto, Ontario, M5S1A8, Canada ; Neurosciences and Mental Health and the Department of Psychiatry, The Hospital for Sick Children 555 University Avenue, Toronto, Ontario, M5G1X8, Canada
| | - Andre Chevrier
- Institute of Medical Science, University of Toronto 7213 Medical Sciences Building, 1 King's College Circle, Toronto, Ontario, M5S1A8, Canada ; Neurosciences and Mental Health and the Department of Psychiatry, The Hospital for Sick Children 555 University Avenue, Toronto, Ontario, M5G1X8, Canada
| | - Russell Schachar
- Institute of Medical Science, University of Toronto 7213 Medical Sciences Building, 1 King's College Circle, Toronto, Ontario, M5S1A8, Canada ; Neurosciences and Mental Health and the Department of Psychiatry, The Hospital for Sick Children 555 University Avenue, Toronto, Ontario, M5G1X8, Canada
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Geier CF, Sweitzer MM, Denlinger R, Sparacino G, Donny EC. Abstinent adult daily smokers show reduced anticipatory but elevated saccade-related brain responses during a rewarded antisaccade task. Psychiatry Res 2014; 223:140-7. [PMID: 24914005 PMCID: PMC5428387 DOI: 10.1016/j.pscychresns.2014.04.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 04/16/2014] [Accepted: 04/16/2014] [Indexed: 10/25/2022]
Abstract
Chronic smoking may result in reduced sensitivity to non-drug rewards (e.g., money), a phenomenon particularly salient during abstinence. During a quit attempt, this effect may contribute to biased decision-making (smoking>alternative reinforcers) and relapse. Although relevant for quitting, characterization of reduced reward function in abstinent smokers remains limited. Moreover, how attenuated reward function affects other brain systems supporting decision-making has not been established. Here, we use a rewarded antisaccade (rAS) task to characterize non-drug reward processing and its influence on inhibitory control, key elements underlying decision-making, in abstinent smokers vs. non-smokers. Abstinent (12-hours) adult daily smokers (N=23) and non-smokers (N=11) underwent fMRI while performing the rAS. Behavioral performances improved on reward vs. neutral trials. Smokers showed attenuated activation in ventral striatum during the reward cue and in superior precentral sulcus and posterior parietal cortex during response preparation, but greater responses during the saccade response in posterior cingulate and parietal cortices. Smokers' attenuated anticipatory responses suggest reduced motivation from monetary reward, while heightened activation during the saccade response suggests that additional circuitry may be engaged later to enhance inhibitory task performance. Overall, this preliminary study highlights group differences in decision-making components and the utility of the rAS to characterize these effects.
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Affiliation(s)
- Charles F Geier
- Department of Human Development and Family Studies, The Pennsylvania State University, University Park, PA 16802, USA
| | - Maggie M Sweitzer
- Department of Psychology, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Rachel Denlinger
- Department of Psychology, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Gina Sparacino
- Department of Psychology, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Eric C Donny
- Department of Psychology, University of Pittsburgh, Pittsburgh, PA 15260, USA
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97
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Dubis JW, Siegel JS, Neta M, Visscher KM, Petersen SE. Tasks Driven by Perceptual Information Do Not Recruit Sustained BOLD Activity in Cingulo-Opercular Regions. Cereb Cortex 2014; 26:192-201. [PMID: 25150283 DOI: 10.1093/cercor/bhu187] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Sustained blood oxygen level dependent (BOLD) signal in the dorsal anterior cingulate cortex/medial superior frontal cortex (dACC/msFC) and bilateral anterior insula/frontal operculum (aI/fO) is found in a broad majority of tasks examined and is believed to function as a putative task set maintenance signal. For example, a meta-analysis investigating task-control signals identified the dorsal anterior cingulate cortex and anterior insula as exhibiting sustained activity across a variety of task types. Re-analysis of tasks included in that meta-analysis showed exceptions, suggesting that tasks where the information necessary to determine a response was present in the stimulus (i.e., perceptually driven) does not show strong sustained cingulo-opercular activity. In a new experiment, we tested the generality of this observation while addressing alternative explanations about sustained cingulo-opercular activity (including task difficulty and verbal vs. non-verbal task demands). A new, difficult, perceptually driven task was compared with 2 new tasks that depended on information beyond that provided by the stimulus. The perceptually driven task showed a lack of cingulo-opercular activity in contrast to the 2 newly constructed tasks. This finding supports the idea that sustained cingulo-opercular activity contributes to maintenance of task set in only a subset of tasks.
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Affiliation(s)
| | | | | | - Kristina M Visscher
- Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Steven E Petersen
- Department of Neurology.,Department of Radiology.,Department of Anatomy and Neurobiology and.,Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA.,Department of Psychology and.,Department of Biomedical Engineering, Washington University in Saint Louis, St. Louis, MO, USA
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98
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Forster S, Nunez-Elizalde AO, Castle E, Bishop SJ. Moderate threat causes longer lasting disruption to processing in anxious individuals. Front Hum Neurosci 2014; 8:626. [PMID: 25191249 PMCID: PMC4137542 DOI: 10.3389/fnhum.2014.00626] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Accepted: 07/26/2014] [Indexed: 11/23/2022] Open
Abstract
Anxiety is associated with increased attentional capture by threat. Previous studies have used simultaneous or briefly separated (<1 s) presentation of threat distractors and target stimuli. Here, we tested the hypothesis that high trait anxious participants would show a longer time window within which distractors cause disruption to subsequent task processing, and that this would particularly be observed for stimuli of moderate or ambiguous threat value. A novel temporally separated emotional distractor task was used. Face or house distractors were presented for 250 ms at short (∼1.6 s) or long (∼3 s) intervals prior to a letter string comprising Xs or Ns. Trait anxiety was associated with slowed identification of letter strings presented at long intervals after face distractors with part surprise/part fear expressions. In other words, these distractors had an impact on high anxious individuals’ speed of target identification seconds after their offset. This was associated with increased activity in the fusiform gyrus and amygdala and reduced dorsal anterior cingulate recruitment. This pattern of activity may reflect impoverished recruitment of reactive control mechanisms to damp down stimulus-specific processing in subcortical and higher visual regions. These findings have implications for understanding how threat-related attentional biases in anxiety may lead to dysfunction in everyday settings where stimuli of moderate, potentially ambiguous, threat value such as those used here are fairly common, and where attentional disruption lasting several seconds may have a profound impact.
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99
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Rebola J, Castelo-Branco M. Visual areas PPA and pSTS diverge from other processing modules during perceptual closure: Functional dichotomies within category selective networks. Neuropsychologia 2014; 61:135-42. [DOI: 10.1016/j.neuropsychologia.2014.06.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Revised: 05/22/2014] [Accepted: 06/09/2014] [Indexed: 11/25/2022]
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100
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Abstract
Previous studies on perceptual decision-making have often emphasized a tight link between decisions and motor intentions. Human decisions, however, also depend on memories or experiences that are not closely tied to specific motor responses. Recent neuroimaging findings have suggested that, during episodic retrieval, parietal activity reflects the accumulation of evidence for memory decisions. It is currently unknown, however, whether these evidence accumulation signals are functionally linked to signals for motor intentions coded in frontoparietal regions and whether activity in the putative memory accumulator tracks the amount of evidence for only previous experience, as reflected in "old" reports, or for both old and new decisions, as reflected in the accuracy of memory judgments. Here, human participants used saccadic-eye and hand-pointing movements to report recognition judgments on pictures defined by different degrees of evidence for old or new decisions. A set of cortical regions, including the middle intraparietal sulcus, showed a monotonic variation of the fMRI BOLD signal that scaled with perceived memory strength (older > newer), compatible with an asymmetrical memory accumulator. Another set, including the hippocampus and the angular gyrus, showed a nonmonotonic response profile tracking memory accuracy (higher > lower evidence), compatible with a symmetrical accumulator. In contrast, eye and hand effector-specific regions in frontoparietal cortex tracked motor intentions but were not modulated by the amount of evidence for the effector outcome. We conclude that item recognition decisions are supported by a combination of symmetrical and asymmetrical accumulation signals largely segregated from motor intentions.
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