scholarly journals Pain Detection and the Privacy of Subjective Experience

2007 ◽  
Vol 33 (2-3) ◽  
pp. 433-456 ◽  
Author(s):  
Adam J. Kolber
Keyword(s):  
Subjective Experience ◽  
Brain Regions ◽  
Physical Pain ◽  
Medical Evidence ◽  
Functional Magnetic Resonance ◽  
Positron Emission ◽  
Pain Symptoms ◽  
The Brain ◽  
Insight Into ◽  
Neuroimaging Techniques

A neurologist with abdominal pain goes to see a gastroenterologist for treatment. The gastroenterologist asks the neurologist where it hurts. The neurologist replies, “In my head, of course.” Indeed, while we can feel pain throughout much of our bodies, pain signals undergo most of their processing in the brain. Using neuroimaging techniques like functional magnetic resonance imaging (“fMRI”) and positron emission tomography (“PET”), researchers have more precisely identified brain regions that enable us to experience physical pain. Certain regions of the brain's cortex, for example, increase in activation when subjects are exposed to painful stimuli. Furthermore, the amount of activation increases with the intensity of the painful stimulus. These findings suggest that we may be able to gain insight into the amount of pain a particular person is experiencing by non-invasively imaging his brain.Such insight could be particularly valuable in the courtroom where we often have no definitive medical evidence to prove or disprove claims about the existence and extent of pain symptoms.

scholarly journals How the Brain Converts Negative Evaluation into Performance Facilitation

2017 ◽  
Vol 28 (2) ◽  
pp. 602-611 ◽  
Author(s):  
Charlotte Prévost ◽  
Hakwan Lau ◽  
Dean Mobbs
Keyword(s):  
Brain Regions ◽  
Negative Evaluation ◽  
Neural Representation ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Success Stories ◽  
Goal Directed Behavior ◽  
The Brain ◽  
Insight Into ◽  
Recurrent Theme

Abstract Surpassing negative evaluation is a recurrent theme of success stories. Yet, there is little evidence supporting the counterintuitive idea that negative evaluation might not only motivate people, but also enhance performance. To address this question, we designed a task that required participants to decide whether taking up a risky challenge after receiving positive or negative evaluations from independent judges. Participants believed that these evaluations were based on their prior performance on a related task. Results showed that negative evaluation caused a facilitation in performance. Concurrent functional magnetic resonance imaging revealed that the motivating effect of negative evaluation was represented in the insula and striatum, while the performance boost was associated with functional positive connectivity between the insula and a set of brain regions involved in goal-directed behavior and the orienting of attention. These findings provide new insight into the neural representation of negative evaluation-induced facilitation.

scholarly journals Variability in Reward Responsivity and Obesity: Evidence from Brain Imaging Studies

2017 ◽  
Author(s):  
Kyle Stanley Burger
Keyword(s):  
Food Intake ◽  
Brain Regions ◽  
Vulnerability Factors ◽  
Imaging Studies ◽  
Vulnerability Model ◽  
Reward Responsivity ◽  
The Brain ◽  
Insight Into ◽  
Neuroimaging Techniques

Advances in neuroimaging techniques have provided insight into the role of the brain in the regulation of food intake and weight. Growing evidence demonstrate that energy dense, palatable foods elicit similar responses in reward-related brain regions that mimic those of addictive substances. Currently, various models of obesity’s relation to reward from food have been theorized. There is evidence to support a theory of hypo-responsivity of reward regions to food, where individuals consume excess amounts to overcome this reward deficit. There is also data to support a theory of hyper-responsivity of reward regions, where individuals who experience greater reward from food intake are at risk for overeating. However, these seemingly discordant theories are static in nature and do not account for the possible effects of repeated overeating on brain responsivity to food and initial vulnerability factors. Here we review data that support these theories and propose a dynamic vulnerability model of obesity that appears to offer a parsimonious theory that accommodates extant findings.

scholarly journals If neuroimaging is the answer, what is the question?

1999 ◽  
Vol 354 (1387) ◽  
pp. 1283-1294 ◽  
Author(s):  
S. M. Kosslyn
Keyword(s):  
Emission Tomography ◽  
Entire System ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Coarse Scale ◽  
Use Patterns ◽  
Positron Emission ◽  
To Come ◽  
The Brain ◽  
Neuroimaging Techniques

It is unclear that we will come to a better understanding of mental processes simply by observing which neural loci are activated while subjects perform a task. Rather, I suggest here that it is better to come armed with a question that directs one to design tasks in ways that take advantage of the strengths of neuroimaging techniques (particularly positron emission tomography and functional magnetic resonance imaging). Here I develop a taxonomy of types of questions that can be easily addressed by such techniques. The first class of questions focuses on how information processing is implemented in the brain; these questions can be posed at a very coarse scale, focusing on the entire system that confers a particular ability, or at increasingly more specific scales, ultimately focusing on individual structures or processes. The second class of questions focuses on specifying when particular processes and structures are invoked; these questions focus on how one can use patterns of activation to infer that specific processes and structures were invoked, and on how processing changes in different circumstances. The use of neuroimaging to address these questions is illustrated with results from experiments on visual cognition, and caveats regarding the logic of inference in each case are noted. Finally, the necessary interplay between neuroimaging and behavioural studies is stressed.

scholarly journals Antagonism between brain regions relevant for cognitive control and emotional memory facilitates the generation of humorous ideas

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Florian Bitsch ◽  
Philipp Berger ◽  
Andreas Fink ◽  
Arne Nagels ◽  
Benjamin Straube ◽  
...  
Keyword(s):  
Cognitive Control ◽  
Positive Emotions ◽  
Emotional Memory ◽  
Brain Regions ◽  
Neural Mechanisms ◽  
Functional Magnetic Resonance ◽  
Frontal Brain ◽  
Successful Resolution ◽  
Neural Underpinnings ◽  
The Brain

AbstractThe ability to generate humor gives rise to positive emotions and thus facilitate the successful resolution of adversity. Although there is consensus that inhibitory processes might be related to broaden the way of thinking, the neural underpinnings of these mechanisms are largely unknown. Here, we use functional Magnetic Resonance Imaging, a humorous alternative uses task and a stroop task, to investigate the brain mechanisms underlying the emergence of humorous ideas in 24 subjects. Neuroimaging results indicate that greater cognitive control abilities are associated with increased activation in the amygdala, the hippocampus and the superior and medial frontal gyrus during the generation of humorous ideas. Examining the neural mechanisms more closely shows that the hypoactivation of frontal brain regions is associated with an hyperactivation in the amygdala and vice versa. This antagonistic connectivity is concurrently linked with an increased number of humorous ideas and enhanced amygdala responses during the task. Our data therefore suggests that a neural antagonism previously related to the emergence and regulation of negative affective responses, is linked with the generation of emotionally positive ideas and may represent an important neural pathway supporting mental health.

scholarly journals Increased sensitivity to strong perturbations in a whole-brain model of LSD

2021 ◽  
Author(s):  
Beatrice M. Jobst ◽  
Selen Atasoy ◽  
Adrián Ponce-Alvarez ◽  
Ana Sanjuán ◽  
Leor Roseman ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
External Perturbation ◽  
Brain Regions ◽  
Lysergic Acid ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Whole Brain ◽  
Response Diversity ◽  
Brain States ◽  
The Brain

AbstractLysergic acid diethylamide (LSD) is a potent psychedelic drug, which has seen a revival in clinical and pharmacological research within recent years. Human neuroimaging studies have shown fundamental changes in brain-wide functional connectivity and an expansion of dynamical brain states, thus raising the question about a mechanistic explanation of the dynamics underlying these alterations. Here, we applied a novel perturbational approach based on a whole-brain computational model, which opens up the possibility to externally perturb different brain regions in silico and investigate differences in dynamical stability of different brain states, i.e. the dynamical response of a certain brain region to an external perturbation. After adjusting the whole-brain model parameters to reflect the dynamics of functional magnetic resonance imaging (fMRI) BOLD signals recorded under the influence of LSD or placebo, perturbations of different brain areas were simulated by either promoting or disrupting synchronization in the regarding brain region. After perturbation offset, we quantified the recovery characteristics of the brain area to its basal dynamical state with the Perturbational Integration Latency Index (PILI) and used this measure to distinguish between the two brain states. We found significant changes in dynamical complexity with consistently higher PILI values after LSD intake on a global level, which indicates a shift of the brain’s global working point further away from a stable equilibrium as compared to normal conditions. On a local level, we found that the largest differences were measured within the limbic network, the visual network and the default mode network. Additionally, we found a higher variability of PILI values across different brain regions after LSD intake, indicating higher response diversity under LSD after an external perturbation. Our results provide important new insights into the brain-wide dynamical changes underlying the psychedelic state - here provoked by LSD intake - and underline possible future clinical applications of psychedelic drugs in particular psychiatric disorders.HighlightsNovel offline perturbational method applied on functional magnetic resonance imaging (fMRI) data under the effect of lysergic acid diethylamide (LSD)Shift of brain’s global working point to more complex dynamics after LSD intakeConsistently longer recovery time after model perturbation under LSD influenceStrongest effects in resting state networks relevant for psychedelic experienceHigher response diversity across brain regions under LSD influence after an external in silico perturbation

scholarly journals Reconstructing feedback representations in ventral visual pathway with a generative adversarial autoencoder

2020 ◽  
Author(s):  
Haider Al-Tahan ◽  
Yalda Mohsenzadeh
Keyword(s):  
Neural Network ◽  
Visual Information ◽  
Visual Pathway ◽  
Functional Magnetic Resonance ◽  
Low Level ◽  
Ventral Visual Pathway ◽  
High Level ◽  
Feedback Connections ◽  
The Brain ◽  
Insight Into

AbstractWhile vision evokes a dense network of feedforward and feedback neural processes in the brain, visual processes are primarily modeled with feedforward hierarchical neural networks, leaving the computational role of feedback processes poorly understood. Here, we developed a generative autoencoder neural network model and adversarially trained it on a categorically diverse data set of images. We hypothesized that the feedback processes in the ventral visual pathway can be represented by reconstruction of the visual information performed by the generative model. We compared representational similarity of the activity patterns in the proposed model with temporal (magnetoencephalography) and spatial (functional magnetic resonance imaging) visual brain responses. The proposed generative model identified two segregated neural dynamics in the visual brain. A temporal hierarchy of processes transforming low level visual information into high level semantics in the feedforward sweep, and a temporally later dynamics of inverse processes reconstructing low level visual information from a high level latent representation in the feedback sweep. Our results append to previous studies on neural feedback processes by presenting a new insight into the algorithmic function and the information carried by the feedback processes in the ventral visual pathway.Author summaryIt has been shown that the ventral visual cortex consists of a dense network of regions with feedforward and feedback connections. The feedforward path processes visual inputs along a hierarchy of cortical areas that starts in early visual cortex (an area tuned to low level features e.g. edges/corners) and ends in inferior temporal cortex (an area that responds to higher level categorical contents e.g. faces/objects). Alternatively, the feedback connections modulate neuronal responses in this hierarchy by broadcasting information from higher to lower areas. In recent years, deep neural network models which are trained on object recognition tasks achieved human-level performance and showed similar activation patterns to the visual brain. In this work, we developed a generative neural network model that consists of encoding and decoding sub-networks. By comparing this computational model with the human brain temporal (magnetoencephalography) and spatial (functional magnetic resonance imaging) response patterns, we found that the encoder processes resemble the brain feedforward processing dynamics and the decoder shares similarity with the brain feedback processing dynamics. These results provide an algorithmic insight into the spatiotemporal dynamics of feedforward and feedback processes in biological vision.

29 POSITRON EMISSION TOMOGRAPHY IMAGING OF BRAIN METABOLISM AND DOPAMINERGIC NEURON DESTRUCTION IN PARKINSON'S DISEASE MODEL PIG

2017 ◽  
Vol 29 (1) ◽  
pp. 122
Author(s):  
H. J. Oh ◽  
J. Moon ◽  
G. A. Kim ◽  
S. Lee ◽  
S. H. Paek ◽  
...  
Keyword(s):  
Positron Emission Tomography ◽  
Dopaminergic Neuron ◽  
Brain Metabolism ◽  
Brain Research ◽  
Brain Regions ◽  
Emission Tomography ◽  
Positron Emission ◽  
Significant Difference ◽  
And Control ◽  
The Brain

Due to similarities between human and porcine, pigs have been proposed as an excellent experimental animal for human medical research. Especially in paediatric brain research, piglets share similarities with human infants in the extent of peak brain growth at the time of birth and the growth pattern of brain. Thus, these findings have supported the wider use of pigs rather than rodents in neuroscience research. Previously, we reported the production of porcine model of Parkinson's disease (PD) by nuclear transfer using donor cell that had been stably infected with lentivirus containing the human α-synuclein gene. The purpose of this study was to determine the alternation of brain metabolism and dopaminergic neuron destruction using noninvasive method in a 2-yr-old PD model and a control pig. The positron emission tomography (PET) scan was done using Biograph TruePoint40 with a TrueV (Siemens, Munich, Germany). The [18F]N-(3-fluoropropyl)-2β-carbomethoxy-3β-(4-iodophenyl) nortropane (FP-CIT) was administrated via the ear vein. Static images of the brain for 15 min were acquired from 2 h after injection. The 18F-fluorodeoxy-D-glucose PET (18F-FDG PET) images of the brain were obtained for 15 min at 45 min post-injection. Computed tomography (CT) scan and magnetic resonance imaging (MRI) were performed at the same location of the brain. In both MRI and CT images, there was no difference in brain regions between PD model and control pigs. However, administration of [18F]FP-CIT was markedly decreased in the bilateral putamen of the PD model pig compared with the control pigs. Moreover, [18F]FP-CIT administration was asymmetrical in the PD model pig but it was symmetrical in control pigs. Regional brain metabolism was also assessed and there was no significant difference in cortical metabolism of PD model and control pigs. We demonstrated that PET imaging could provide a foundation for translational Parkinson neuroimaging in transgenic pigs. In the present study, a 2-yr-old PD model pig showed dopaminergic neuron destruction in brain regions. Therefore, PD model pig expressing human α-synuclein gene would be an efficient model for human PD patients. This study was supported by Korea IPET (#311011–05–5-SB010), Research Institute for Veterinary Science, TS Corporation and the BK21 plus program.

Where Is Size in the Brain of the Beholder?

2015 ◽  
Vol 28 (3-4) ◽  
pp. 285-296 ◽  
Author(s):  
Dietrich Samuel Schwarzkopf
Keyword(s):  
Subjective Experience ◽  
Visual Space ◽  
Brain Regions ◽  
Future Research ◽  
The Brain

Despite advances in our understanding of how the brain represents visual space, it remains unresolved how the subjective experience of an object’s size arises. While responses in retinotopic cortex correlate with perceived size, this does not imply that those brain regions mediate perceived size differences. Here I describe how the percept of an object’s size could be generated in the brain and outline unanswered questions that future research should seek to address.

scholarly journals Medial Orbitofrontal Cortex Is Associated with Fatigue Sensation

2010 ◽  
Vol 2010 ◽  
pp. 1-5 ◽  
Author(s):  
Seiki Tajima ◽  
Shigeyuki Yamamoto ◽  
Masaaki Tanaka ◽  
Yosky Kataoka ◽  
Masao Iwase ◽  
...  
Keyword(s):  
Positron Emission Tomography ◽  
Orbitofrontal Cortex ◽  
Brain Region ◽  
Statistical Parametric Mapping ◽  
Brain Regions ◽  
Mapping Method ◽  
Emission Tomography ◽  
Neural Basis ◽  
Positron Emission ◽  
The Brain

Fatigue is an indispensable bioalarm to avoid exhaustive state caused by overwork or stresses. It is necessary to elucidate the neural mechanism of fatigue sensation for managing fatigue properly. We performedH2O  15positron emission tomography scans to indicate neural activations while subjects were performing 35-min fatigue-inducing task trials twice. During the positron emission tomography experiment, subjects performed advanced trail-making tests, touching the target circles in sequence located on the display of a touch-panel screen. In order to identify the brain regions associated with fatigue sensation, correlation analysis was performed using statistical parametric mapping method. The brain region exhibiting a positive correlation in activity with subjective sensation of fatigue, measured immediately after each positron emission tomography scan, was located in medial orbitofrontal cortex (Brodmann's area 10/11). Hence, the medial orbitofrontal cortex is a brain region associated with mental fatigue sensation. Our findings provide a new perspective on the neural basis of fatigue.

scholarly journals A review of the new minimally invasive brain stimulation techniques in psychiatry

2001 ◽  
Vol 23 (2) ◽  
pp. 100-109 ◽  
Author(s):  
Jeong-Ho Chae ◽  
Xingbao Li ◽  
Ziad Nahas ◽  
F. Andrew Kozel ◽  
Mark S. George
Keyword(s):  
Minimally Invasive ◽  
Brain Stimulation ◽  
Functional Neuroimaging ◽  
Neuropsychiatric Disorders ◽  
Brain Regions ◽  
Therapeutic Tools ◽  
Invasive Techniques ◽  
The Brain ◽  
Neuroimaging Techniques ◽  
Deep Brain

New knowledge about the specific brain regions involved in neuropsychiatric disorders is rapidly evolving due to recent advances in functional neuroimaging techniques. The ability to stimulate the brain in awake alert adults without neurosurgery is a real advance that neuroscientists have long dreamed for. Several novel and minimally invasive techniques to stimulate the brain have recently developed. Among these newer somatic interventions, transcranial magnetic stimulation (TMS), vagus nerve stimulation (VNS) and deep brain stimulation (DBS) show promise as therapeutic tools in the treatment of neuropsychiatric disorders. This article reviews the history, methodology, and the future of these minimally invasive brain stimulation (MIBS) techniques and their emerging research and therapeutic applications in psychiatry

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