scholarly journals Supracortical consciousness: Insights from temporal dynamics, processing-content, and olfaction

2007 ◽  
Vol 30 (1) ◽  
pp. 100-100 ◽  
Author(s):  
Ezequiel Morsella ◽  
John A. Bargh
Keyword(s):  
Temporal Dynamics ◽  
Neural Correlates ◽  
Temporal Relation

To further illuminate the nature of conscious states, it may be progressive to integrate Merker's important contribution with what is known regarding (a) the temporal relation between conscious states and activation of the mesodiencephalic system; (b) the nature of the information (e.g., perceptual vs. premotor) involved in conscious integration; and (c) the neural correlates of olfactory consciousness.

Slow Temporal Dynamics of Motion-Induced Brightness Shift Reveals Impact of Adaptation

Perception ◽  
2019 ◽  
Vol 48 (5) ◽  
pp. 402-411
Author(s):  
Sang Wook Hong ◽  
Min-Suk Kang
Keyword(s):  
Temporal Dynamics ◽  
Time Window ◽  
Neural Adaptation ◽  
Moving Object ◽  
Temporal Relation ◽  
Surface Reflectance ◽  
Ambient Illumination ◽  
Stationary Object ◽  
Motion Onset

Brightness of an object is determined by various factors including ambient illumination, surface reflectance of the object, and spatial and temporal relation between the object and its surrounding context. Recently, it has been demonstrated that the motion of an object alters its own and nearby object’s appearance such as brightness and color. This study aims to unveil mechanisms of the motion-induced brightness shift by measuring its temporal dynamics. We found that the motion-induced brightness shift occurred instantaneously with the motion onset when the motion was introduced abruptly. However, the brightness of a stationary object was altered gradually by a nearby moving object in about 2 s time window when the stationary dot was introduced abruptly. Two distinct temporal dynamics (slow vs. fast) of the motion-induced brightness shift demonstrate that both slow neural adaptation and fast neural normalization processes determine the brightness shift induced by the object’s motion.

scholarly journals Common and Unique Neural Correlates of Autobiographical Memory and Theory of Mind

2010 ◽  
Vol 22 (6) ◽  
pp. 1095-1111 ◽  
Author(s):  
Jennifer S. Rabin ◽  
Asaf Gilboa ◽  
Donald T. Stuss ◽  
Raymond A. Mar ◽  
R. Shayna Rosenbaum
Keyword(s):  
Theory Of Mind ◽  
Autobiographical Memory ◽  
Temporal Dynamics ◽  
Mental States ◽  
Neural Correlates ◽  
Brain Regions ◽  
Fmri Study ◽  
Common Activity ◽  
The Right ◽  
Past Experiences

There is an inconsistency regarding the relationship between thinking about personal past experiences during autobiographical memory (AM) and thinking about other people's mental states during theory of mind (ToM). Neuroimaging studies of AM and ToM consistently report overlap in the brain regions recruited. Lesion data, however, show that amnesic people with AM impairment can have intact ToM, suggesting that distinct neural mechanisms support these abilities [Rosenbaum, R. S., Stuss, D. T., Levine, B., & Tulving, E. Theory of mind is independent of episodic memory. Science, 318, 1257, 2007]. The current fMRI study examined the functional and neural correlates of remembering one's own experiences in response to personal photos (AM condition) and imagining others' experiences in response to strangers' photos (ToM condition). AM and ToM conditions were matched in terms of content and vividness, and were compared directly and to a common baseline. Analyses revealed common activity within frontal and temporal–parietal regions, yet midline structures exhibited greater activity during AM. More specific analyses of event construction and detail elaboration revealed unique activation of the right hippocampus during AM construction, and of lateral regions, such as the right temporo-parietal junction (TPJ) during ToM elaboration. Moreover, a region of left hippocampus/perirhinal cortex appeared to be driven by event vividness. Thus, differences in AM and ToM emerge when a common baseline is used and temporal dynamics are taken into account. Furthermore, the right TPJ and related lateral regions, and not the hippocampus, may be needed for ToM, given that this ability is intact in amnesic people.

Mind over matter – what do we know about neuroplasticity in adults?

2014 ◽  
Vol 26 (6) ◽  
pp. 891-909 ◽  
Author(s):  
Vyara Valkanova ◽  
Rocio Eguia Rodriguez ◽  
Klaus P. Ebmeier
Keyword(s):  
Structural Changes ◽  
Temporal Dynamics ◽  
Gray Matter Volume ◽  
Neural Correlates ◽  
Structure And Function ◽  
Resonance Imaging ◽  
Matter Volume ◽  
Upper Limits ◽  
Longitudinal Imaging ◽  
And Function

ABSTRACTBackground:An increasing number of studies have examined the effects of training of cognitive and other tasks on brain structure, using magnetic resonance imaging.Methods:Studies combining cognitive and other tasks training with longitudinal imaging designs were reviewed, with a view to identify paradigms potentially applicable to treatment of cognitive impairment.Results:We identified 36 studies, employing training as variable as juggling, working memory, meditation, learning abstract information, and aerobic exercise. There were training-related structural changes, increases in gray matter volume, decreases, increases and decreases in different regions, or no change at all. There was increased integrity in white matter following training, but other patterns of results were also reported.Conclusions:Questions still to be answered are: Are changes due to use-dependent effects or are they specific to learning? What are the underlying neural correlates of learning, the temporal dynamics of changes, the relations between structure and function, and the upper limits of improvement? How can gains be maintained? The question whether neuroplasticity will contribute to the treatment of dementia will need to be posed again at that stage.

scholarly journals Neural correlates of sign language production revealed by electrocorticography

Neurology ◽  
2020 ◽  
Vol 95 (21) ◽  
pp. e2880-e2889
Author(s):  
Jennifer Shum ◽  
Lora Fanda ◽  
Patricia Dugan ◽  
Werner K. Doyle ◽  
Orrin Devinsky ◽  
...  
Keyword(s):  
American Sign Language ◽  
Sign Language ◽  
Speech Production ◽  
Language Processing ◽  
Language Production ◽  
Temporal Dynamics ◽  
Neural Correlates ◽  
Multiple Modalities ◽  
Neurosurgical Patient ◽  
Superior Parietal Cortex

ObjectiveThe combined spatiotemporal dynamics underlying sign language production remain largely unknown. To investigate these dynamics compared to speech production, we used intracranial electrocorticography during a battery of language tasks.MethodsWe report a unique case of direct cortical surface recordings obtained from a neurosurgical patient with intact hearing who is bilingual in English and American Sign Language. We designed a battery of cognitive tasks to capture multiple modalities of language processing and production.ResultsWe identified 2 spatially distinct cortical networks: ventral for speech and dorsal for sign production. Sign production recruited perirolandic, parietal, and posterior temporal regions, while speech production recruited frontal, perisylvian, and perirolandic regions. Electrical cortical stimulation confirmed this spatial segregation, identifying mouth areas for speech production and limb areas for sign production. The temporal dynamics revealed superior parietal cortex activity immediately before sign production, suggesting its role in planning and producing sign language.ConclusionsOur findings reveal a distinct network for sign language and detail the temporal propagation supporting sign production.

scholarly journals Distinct cortical codes and temporal dynamics for conscious and unconscious percepts

eLife ◽  
2015 ◽  
Vol 4 ◽  
Author(s):  
Moti Salti ◽  
Simo Monto ◽  
Lucie Charles ◽  
Jean-Remi King ◽  
Lauri Parkkonen ◽  
...  
Keyword(s):  
Temporal Dynamics ◽  
Spatial Location ◽  
Neural Correlates ◽  
Multivariate Pattern Analysis ◽  
Neuronal Coding ◽  
Slow Decay ◽  
Novel Approach ◽  
Brain Responses ◽  
Multivariate Pattern ◽  
Post Onset

The neural correlates of consciousness are typically sought by comparing the overall brain responses to perceived and unperceived stimuli. However, this comparison may be contaminated by non-specific attention, alerting, performance, and reporting confounds. Here, we pursue a novel approach, tracking the neuronal coding of consciously and unconsciously perceived contents while keeping behavior identical (blindsight). EEG and MEG were recorded while participants reported the spatial location and visibility of a briefly presented target. Multivariate pattern analysis demonstrated that considerable information about spatial location traverses the cortex on blindsight trials, but that starting ≈270 ms post-onset, information unique to consciously perceived stimuli, emerges in superior parietal and superior frontal regions. Conscious access appears characterized by the entry of the perceived stimulus into a series of additional brain processes, each restricted in time, while the failure of conscious access results in the breaking of this chain and a subsequent slow decay of the lingering unconscious activity.

scholarly journals Early and late Cortical responses to directly gazing faces are task-dependent

2017 ◽  
Author(s):  
Nicolas Burra ◽  
David Framorando ◽  
Alan J. Pegna
Keyword(s):  
Face Processing ◽  
Gender Discrimination ◽  
Temporal Dynamics ◽  
Neural Correlates ◽  
Event Related Potential ◽  
Neural Responses ◽  
Gaze Perception ◽  
Direct Gaze ◽  
Cortical Responses ◽  
Human Faces

Gender categorisation of human faces is facilitated when gaze is directed toward the observer (i.e., a direct gaze), compared to situations where gaze is averted or the eyes are closed (Macrae, Hood, Milne, Rowe, & Mason, 2002). However, the temporal dynamics underlying this phenomenon remain to some extent unknown. Here, we used electroencephalography (EEG) to assess the neural correlates of this effect, focusing on the event-related potential (ERP) components known to be sensitive to gaze perception, i.e., P1, N170, and P3b. We first replicated the seminal findings of Macrae et al. (Experiment 1) regarding facilitated gender discrimination, and subsequently measured the underlying neural responses. Our data revealed an early preferential processing of direct gaze as compared to averted gaze and closed eyes at the P1, which reverberated at the P3b (Experiment 2). Critically, using the same material, we failed to reproduce these effects when gender categorisation was not required (Experiment 3). Taken together, our data confirm that direct gaze enhances both early and late cortical responses to face processing, although this effect appears to be task-dependent.

Sign in / Sign up

Export Citation Format

Share Document