Resting-State Functional Connectivity of the Locus Coeruleus in Humans: In Comparison with the Ventral Tegmental Area/Substantia Nigra Pars Compacta and the Effects of Age
The locus coeruleus (LC) provides the primary noradrenergic inputs to the cerebral cortex. Despite numerous animal studies documenting the functions of the LC, research in humans is hampered by the small volume of this midbrain nucleus. Here, we took advantage of a probabilistic template, explored the cerebral functional connectivity of the LC with resting-state fMRI data of 250 healthy adults, and verified the findings by accounting for physiological noise in another data set. In addition, we contrasted connectivities of the LC and the ventral tegmental area/substantia nigra pars compacta. The results highlighted both sha...
Source: Cerebral Cortex - July 24, 2016 Category: Neurology Authors: Zhang, S., Hu, S., Chao, H. H., Li, C.-S. R. Tags: Original Articles Source Type: research
Visual and Haptic Shape Processing in the Human Brain: Unisensory Processing, Multisensory Convergence, and Top-Down Influences
Humans are highly adept at multisensory processing of object shape in both vision and touch. Previous studies have mostly focused on where visually perceived object-shape information can be decoded, with haptic shape processing receiving less attention. Here, we investigate visuo-haptic shape processing in the human brain using multivoxel correlation analyses. Importantly, we use tangible, parametrically defined novel objects as stimuli. Two groups of participants first performed either a visual or haptic similarity-judgment task. The resulting perceptual object-shape spaces were highly similar and matched the physical par...
Source: Cerebral Cortex - July 24, 2016 Category: Neurology Authors: Lee Masson, H., Bulthe, J., Op de Beeck, H. P., Wallraven, C. Tags: Original Articles Source Type: research
Decoding Concrete and Abstract Action Representations During Explicit and Implicit Conceptual Processing
Action understanding requires a many-to-one mapping of perceived input onto abstract representations that generalize across concrete features. It is debated whether such abstract action concepts are encoded in ventral premotor cortex (PMv; motor hypothesis) or, alternatively, are represented in lateral occipitotemporal cortex (LOTC; cognitive hypothesis). We used fMRI-based multivoxel pattern analysis to decode observed actions at concrete and abstract, object-independent levels of representation. Participants observed videos of 2 actions involving 2 different objects, using either an explicit or implicit task with respect...
Source: Cerebral Cortex - July 24, 2016 Category: Neurology Authors: Wurm, M. F., Ariani, G., Greenlee, M. W., Lingnau, A. Tags: Original Articles Source Type: research
Default Mode Network Activity Predicts Early Memory Decline in Healthy Young Adults Aged 18-31
Functional magnetic resonance imaging (fMRI) research conducted in healthy young adults is typically done with the assumption that this sample is largely homogeneous. However, studies from cognitive psychology suggest that long-term memory and attentional control begin to diminish in the third decade of life. Here, 100 participants between the ages of 18 and 31 learned Lithuanian translations of English words in an individual differences study using fMRI. Long-term memory ability was operationalized for each participant by deriving a memory score from 3 convergent measures. Age of participant predicted memory score in this...
Source: Cerebral Cortex - July 24, 2016 Category: Neurology Authors: Nelson, S. M., Savalia, N. K., Fishell, A. K., Gilmore, A. W., Zou, F., Balota, D. A., McDermott, K. B. Tags: Original Articles Source Type: research
Cortical Gray and Adjacent White Matter Demonstrate Synchronous Maturation in Very Preterm Infants
Spatial and functional gradients of development have been described for the maturation of cerebral gray and white matter using histological and radiological approaches. We evaluated these patterns in very preterm (VPT) infants using diffusion tensor imaging. Data were obtained from 3 groups: 1) 22 VPT infants without white matter injury (WMI), of whom all had serial MRI studies during the neonatal period, 2) 19 VPT infants with WMI, of whom 3 had serial MRI studies and 3) 12 healthy, term-born infants. Regions of interest were placed in the cortical gray and adjacent white matter in primary motor, primary visual, visual as...
Source: Cerebral Cortex - July 24, 2016 Category: Neurology Authors: Smyser, T. A., Smyser, C. D., Rogers, C. E., Gillespie, S. K., Inder, T. E., Neil, J. J. Tags: Original Articles Source Type: research
Regulation of Cortical Dynamic Range by Background Synaptic Noise and Feedforward Inhibition
The cortex encodes a broad range of inputs. This breadth of operation requires sensitivity to weak inputs yet non-saturating responses to strong inputs. If individual pyramidal neurons were to have a narrow dynamic range, as previously claimed, then staggered all-or-none recruitment of those neurons would be necessary for the population to achieve a broad dynamic range. Contrary to this explanation, we show here through dynamic clamp experiments in vitro and computer simulations that pyramidal neurons have a broad dynamic range under the noisy conditions that exist in the intact brain due to background synaptic input. Feed...
Source: Cerebral Cortex - July 24, 2016 Category: Neurology Authors: Khubieh, A., Ratte, S., Lankarany, M., Prescott, S. A. Tags: Original Articles Source Type: research
Context-Dependent Duration Signals in the Primate Prefrontal Cortex
The activity of some prefrontal (PF) cortex neurons distinguishes short from long time intervals. Here, we examined whether this property reflected a general timing mechanism or one dependent on behavioral context. In one task, monkeys discriminated the relative duration of 2 stimuli; in the other, they discriminated the relative distance of 2 stimuli from a fixed reference point. Both tasks had a pre-cue period (interval 1) and a delay period (interval 2) with no discriminant stimulus. Interval 1 elapsed before the presentation of the first discriminant stimulus, and interval 2 began after that stimulus. Both intervals ha...
Source: Cerebral Cortex - July 24, 2016 Category: Neurology Authors: Genovesio, A., Seitz, L. K., Tsujimoto, S., Wise, S. P. Tags: Original Articles Source Type: research
Timing of Cortico-Muscle Transmission During Active Movement
Numerous studies have reported large disparities between short cortico-muscle conduction latencies and long recorded delays between cortical firing and evoked muscle activity. Using methods such as spike- and stimulus-triggered averaging of electromyographic (EMG) activity, previous studies have shown that the time delay between corticomotoneuronal (CM) cell firing and onset of facilitation of forelimb muscle activity ranges from 6.7 to 9.8 ms, depending on the muscle group tested. In contrast, numerous studies have reported delays of 60–122 ms between cortical cell firing onset and either EMG or movement onset durin...
Source: Cerebral Cortex - July 24, 2016 Category: Neurology Authors: Van Acker, G. M., Luchies, C. W., Cheney, P. D. Tags: Original Articles Source Type: research
Celsr3 and Fzd3 Organize a Pioneer Neuron Scaffold to Steer Growing Thalamocortical Axons
Celsr3 and Fzd3 regulate the development of reciprocal thalamocortical projections independently of their expression in cortical or thalamic neurons. To understand this cell non autonomous mechanism further, we tested whether Celsr3 and Fzd3 could act via Isl1-positive guidepost cells. Isl1-positive cells appear in the forebrain at embryonic day (E) 9.5-E10.5 and, from E12.5, they form 2 contingents in ventral telencephalon and prethalamus. In control mice, corticothalamic axons run in the ventral telencephalic corridor in close contact with Isl1-positive cells. When Celsr3 or Fzd3 is inactivated in Isl1-expressing cells, ...
Source: Cerebral Cortex - June 7, 2016 Category: Neurology Authors: Feng, J., Xian, Q., Guan, T., Hu, J., Wang, M., Huang, Y., So, K.-F., Evans, S. M., Chai, G., Goffinet, A. M., Qu, Y., Zhou, L. Tags: Articles Source Type: research
Neural Representations of Natural and Scrambled Movies Progressively Change from Rat Striate to Temporal Cortex
We presented natural movies containing a rat or no rat as well as their phase-scrambled versions. Population analyses showed increased dissociation in representations of natural versus scrambled stimuli along the targeted stream, but without a clear preference for natural stimuli. Along the measured cortical hierarchy the neural response seemed to be driven increasingly by features that are not V1-like and destroyed by phase-scrambling. However, there was no evidence for category selectivity for the rat versus nonrat distinction. Together, these findings provide insights about differences and commonalities between rodent a...
Source: Cerebral Cortex - June 7, 2016 Category: Neurology Authors: Vinken, K., Van den Bergh, G., Vermaercke, B., Op de Beeck, H. P. Tags: Articles Source Type: research
Relationship Between Cortical Gyrification, White Matter Connectivity, and Autism Spectrum Disorder
Autism spectrum disorder (ASD) is a complex neurodevelopmental condition, which is accompanied by differences in gray matter neuroanatomy and white matter connectivity. However, it is unknown whether these differences are linked or reflect independent aetiologies. Using a multimodal neuroimaging approach, we therefore examined 51 male adults with ASD and 48 neurotypical controls to investigate the relationship between gray matter local gyrification (lGI) and white matter diffusivity in associated fiber tracts. First, ASD individuals had a significant increase in gyrification around the left pre- and post-central gyrus. Sec...
Source: Cerebral Cortex - June 7, 2016 Category: Neurology Authors: Ecker, C., Andrews, D., Dell'Acqua, F., Daly, E., Murphy, C., Catani, M., Thiebaut de Schotten, M., Baron-Cohen, S., Lai, M. C., Lombardo, M. V., Bullmore, E. T., Suckling, J., Williams, S., Jones, D. K., Chiocchetti, A., the MRC AIMS Consortium, Murphy, Tags: Articles Source Type: research
Network-Level Structure-Function Relationships in Human Neocortex
The dynamics of spontaneous fluctuations in neural activity are shaped by underlying patterns of anatomical connectivity. While numerous studies have demonstrated edge-wise correspondence between structural and functional connections, much less is known about how large-scale coherent functional network patterns emerge from the topology of structural networks. In the present study, we deploy a multivariate statistical technique, partial least squares, to investigate the association between spatially extended structural networks and functional networks. We find multiple statistically robust patterns, reflecting reliable comb...
Source: Cerebral Cortex - June 7, 2016 Category: Neurology Authors: Misic, B., Betzel, R. F., de Reus, M. A., van den Heuvel, M. P., Berman, M. G., McIntosh, A. R., Sporns, O. Tags: Articles Source Type: research
Role of the Perigenual Anterior Cingulate and Orbitofrontal Cortex in Contingency Learning in the Marmoset
Two learning mechanisms contribute to decision-making: goal-directed actions and the "habit" system, by which action-outcome and stimulus-response associations are formed, respectively. Rodent lesion studies and human neuroimaging have implicated both the medial prefrontal cortex (mPFC) and the orbitofrontal cortex (OFC) in the neural basis of contingency learning, a critical component of goal-directed actions, though some published findings are conflicting. We sought to reconcile the existing literature by comparing the effects of excitotoxic lesions of the perigenual anterior cingulate cortex (pgACC), a region of the mPF...
Source: Cerebral Cortex - June 7, 2016 Category: Neurology Authors: Jackson, S. A. W., Horst, N. K., Pears, A., Robbins, T. W., Roberts, A. C. Tags: Articles Source Type: research
Plasticity-Related Gene 1 Affects Mouse Barrel Cortex Function via Strengthening of Glutamatergic Thalamocortical Transmission
Plasticity-related gene-1 (PRG-1) is a brain-specific protein that modulates glutamatergic synaptic transmission. Here we investigated the functional role of PRG-1 in adolescent and adult mouse barrel cortex both in vitro and in vivo. Compared with wild-type (WT) animals, PRG-1-deficient (KO) mice showed specific behavioral deficits in tests assessing sensorimotor integration and whisker-based sensory discrimination as shown in the beam balance/walking test and sandpaper tactile discrimination test, respectively. At P25-31, spontaneous network activity in the barrel cortex in vivo was higher in KO mice compared with WT lit...
Source: Cerebral Cortex - June 7, 2016 Category: Neurology Authors: Unichenko, P., Kirischuk, S., Yang, J.-W., Baumgart, J., Roskoden, T., Schneider, P., Sommer, A., Horta, G., Radyushkin, K., Nitsch, R., Vogt, J., Luhmann, H. J. Tags: Articles Source Type: research
High-Resolution Functional Connectivity Density: Hub Locations, Sensitivity, Specificity, Reproducibility, and Reliability
Brain regions with high connectivity have high metabolic cost and their disruption is associated with neuropsychiatric disorders. Prior neuroimaging studies have identified at the group-level local functional connectivity density (lFCD) hubs, network nodes with high degree of connectivity with neighboring regions, in occipito-parietal cortices. However, the individual patterns and the precision for the location of the hubs were limited by the restricted spatiotemporal resolution of the magnetic resonance imaging (MRI) measures collected at rest. In this work, we show that MRI datasets with higher spatiotemporal resolution ...
Source: Cerebral Cortex - June 7, 2016 Category: Neurology Authors: Tomasi, D., Shokri-Kojori, E., Volkow, N. D. Tags: Articles Source Type: research
