scholarly journals Contribution of linear and nonlinear mechanisms to predictive motion estimation

2021 ◽  
Author(s):  
Belle Liu ◽  
Arthur Hong ◽  
Fred Rieke ◽  
Michael B. Manookin
Keyword(s):  
Neural Circuits ◽  
Sensory Systems ◽  
Neural Systems ◽  
Sparse Signal ◽  
Response Suppression ◽  
Delayed Response ◽  
Signal Integration ◽  
Linear And Nonlinear ◽  
Successful Behavior ◽  
The Brain

Successful behavior relies on the ability to use information obtained from past experience to predict what is likely to occur in the future. A salient example of predictive encoding comes from the vertebrate retina, where neural circuits encode information that can be used to estimate the trajectory of a moving object. Predictive computations should be a general property of sensory systems, but the features needed to identify these computations across neural systems are not well understood. Here, we identify several properties of predictive computations in the primate retina that likely generalize across sensory systems. These features include calculating the derivative of incoming signals, sparse signal integration, and delayed response suppression. These findings provide a deeper understanding of how the brain carries out predictive computations and identify features that can be used to recognize these computations throughout the brain.

scholarly journals Intergenerational neural mediators of early-life anxious temperament

2015 ◽  
Vol 112 (29) ◽  
pp. 9118-9122 ◽  
Author(s):  
Andrew S. Fox ◽  
Jonathan A. Oler ◽  
Alexander J. Shackman ◽  
Steven E. Shelton ◽  
Muthuswamy Raveendran ◽  
...  
Keyword(s):  
Rhesus Monkeys ◽  
Brain Metabolism ◽  
Neural Circuits ◽  
Brain Volume ◽  
Neural Systems ◽  
Anxiety And Depression ◽  
Family Tree ◽  
Child Transmission ◽  
The Family ◽  
The Brain

Understanding the heritability of neural systems linked to psychopathology is not sufficient to implicate them as intergenerational neural mediators. By closely examining how individual differences in neural phenotypes and psychopathology cosegregate as they fall through the family tree, we can identify the brain systems that underlie the parent-to-child transmission of psychopathology. Although research has identified genes and neural circuits that contribute to the risk of developing anxiety and depression, the specific neural systems that mediate the inborn risk for these debilitating disorders remain unknown. In a sample of 592 young rhesus monkeys that are part of an extended multigenerational pedigree, we demonstrate that metabolism within a tripartite prefrontal-limbic-midbrain circuit mediates some of the inborn risk for developing anxiety and depression. Importantly, although brain volume is highly heritable early in life, it is brain metabolism—not brain structure—that is the critical intermediary between genetics and the childhood risk to develop stress-related psychopathology.

scholarly journals From embodying tool to embodying alien limb: sensory-motor modulation of personal and extrapersonal space

2021 ◽  
Vol 22 (S1) ◽  
pp. 121-126
Author(s):  
Anna Berti
Keyword(s):  
Neural Circuits ◽  
Personal Space ◽  
Peripersonal Space ◽  
The Body ◽  
Neural Systems ◽  
Body Representations ◽  
Alien Limb ◽  
Extrapersonal Space ◽  
Sensory Motor ◽  
The Brain

AbstractYears ago, it was demonstrated (e.g., Rizzolatti et al. in Handbook of neuropsychology, Elsevier Science, Amsterdam, 2000) that the brain does not encode the space around us in a homogeneous way, but through neural circuits that map the space relative to the distance that objects of interest have from the body. In monkeys, relatively discrete neural systems, characterized by neurons with specific neurophysiological responses, seem to be dedicated either to represent the space that can be reached by the hand (near/peripersonal space) or to the distant space (far/extrapersonal space). It was also shown that the encoding of spaces has dynamic aspects because they can be remapped by the use of tools that trigger different actions (e.g., Iriki et al. 1998). In this latter case, the effect of the tool depends on the modulation of personal space, that is the space of our body. In this paper, I will review and discuss selected research, which demonstrated that also in humans: 1 spaces are encoded in a dynamic way; 2 encoding can be modulated by the use of tool that the system comes to consider as parts of the own body; 3 body representations are not fixed, but they are fragile and subject to change to the point that we can incorporate not only the tools necessary for action, but even limbs belonging to other people. What embodiment of tools and of alien limb tell us about body representations is then briefly discussed.

Evidence from Lightness and Color

2019 ◽  
pp. 75-88
Author(s):  
Dale Purves
Keyword(s):  
Physical World ◽  
Sensory Systems ◽  
Frequency Of Occurrence ◽  
Brain System ◽  
Ranking Theory ◽  
Physical Measurements ◽  
The Senses ◽  
Successful Behavior ◽  
The Brain

What, then, is the evidence that sensory systems link stimulus inputs to useful responses empirically as a means of generating successful behavior in a physical world that the senses cannot measure? This chapter focuses on evidence derived from studies of lightness and color in vision, the brain system that has been most extensively studied in this regard. The argument here, and in the following chapters that consider other perceptual qualities and systems, is that evolved circuitry based on accumulated experience with frequency of occurrence of biologically useful stimuli accomplishes this feat. This strategy, called empirical ranking theory, explains why the qualities we perceive are always at odds with physical measurements.

scholarly journals A mechanism for synaptic copy between neural circuits

2018 ◽  
Author(s):  
Yuxiu Shao ◽  
Binxu Wang ◽  
Andrew T. Sornborger ◽  
Louis Tao
Keyword(s):  
Memory Consolidation ◽  
Information Transfer ◽  
Neural Circuits ◽  
Neural Circuit ◽  
Neural Systems ◽  
Long Term Memory ◽  
Cortical Oscillations ◽  
The Brain ◽  
Putative Mechanism

The brain has a central, short-term learning module, the hippocampus, which transfers what it has learned to long-term memory in cortex during non-REM sleep. The putative mechanism responsible for this type of memory consolidation invokes hierarchically nested hippocampal ripples (100-250 Hz), thalamo-cortical spindles (7-15 Hz), and cortical slow oscillations (< 1 Hz) to enable transfer. Suppression of, for instance, thalamic spindles has been shown to impair hippocampus-dependent memory consolidation. Cortical oscillations are central to information transfer in neural systems. Significant evidence supports the idea that coincident spike input can allow the neural threshold to be overcome, and spikes to be propagated downstream in a circuit. Thus, an observation of oscillations in neural circuits would be an indication that repeated synchronous spiking is enabling information transfer. However, for memory transfer, in which synaptic weights must be being transferred from one neural circuit (region) to another, what is the mechanism? Here, we present a synaptic transfer mechanism whose structure provides some understanding of the phenomena that have been implicated in memory transfer, including the nested oscillations at various frequencies. The circuit is based on the principle of pulse-gated, graded information transfer between neural populations.PACS numbers: 87.18.Sn,87.19.lj,87.19.lm,87.19.lq

scholarly journals Deciphering the Brain's Codes

1991 ◽  
Vol 3 (1) ◽  
pp. 1-18 ◽  
Author(s):  
Masakazu Konishi
Keyword(s):  
Neural Network ◽  
Signal Processing ◽  
Lower Order ◽  
Stimulus Pattern ◽  
Neural Circuits ◽  
Sensory Systems ◽  
Hierarchical Design ◽  
Motor Systems ◽  
Parallel Channels ◽  
The Brain

The two sensory systems discussed in this review use similar algorithms for the synthesis of the neuronal selectivity for the stimulus that releases a particular behavior, although the neural circuits, the brain sites involved, and even the species are different. This stimulus selectivity emerges gradually in a neural network organized according to parallel and hierarchical design principles. The parallel channels contain lower order stations with special circuits for the creation of neuronal selectivities for different features of the stimulus. Convergence of the parallel pathways brings these selectivities together at a higher order station for the eventual synthesis of the selectivity for the whole stimulus pattern. The neurons that are selective for the stimulus are at the top of the hierarchy, and they form the interface between the sensory and motor systems or between sensory systems of different modalities. The similarities of these two systems at the level of algorithms suggest the existence of rules of signal processing that transcend different sensory systems and species of animals.

scholarly journals Brain mast cells link the immune system to anxiety-like behavior

2008 ◽  
Vol 105 (46) ◽  
pp. 18053-18057 ◽  
Author(s):  
Katherine M. Nautiyal ◽  
Ana C. Ribeiro ◽  
Donald W. Pfaff ◽  
Rae Silver
Keyword(s):  
Mast Cell ◽  
Mast Cells ◽  
Cell Activation ◽  
Mast Cell Activation ◽  
Neural Systems ◽  
Loss Of Function ◽  
Littermate Control ◽  
Cytokines And Chemokines ◽  
Function Models ◽  
The Brain

Mast cells are resident in the brain and contain numerous mediators, including neurotransmitters, cytokines, and chemokines, that are released in response to a variety of natural and pharmacological triggers. The number of mast cells in the brain fluctuates with stress and various behavioral and endocrine states. These properties suggest that mast cells are poised to influence neural systems underlying behavior. Using genetic and pharmacological loss-of-function models we performed a behavioral screen for arousal responses including emotionality, locomotor, and sensory components. We found that mast cell deficient KitW−sh/W−sh (sash−/−) mice had a greater anxiety-like phenotype than WT and heterozygote littermate control animals in the open field arena and elevated plus maze. Second, we show that blockade of brain, but not peripheral, mast cell activation increased anxiety-like behavior. Taken together, the data implicate brain mast cells in the modulation of anxiety-like behavior and provide evidence for the behavioral importance of neuroimmune links.

scholarly journals The emulation theory of representation: Motor control, imagery, and perception

2004 ◽  
Vol 27 (3) ◽  
pp. 377-396 ◽  
Author(s):  
Rick Grush
Keyword(s):  
Motor Control ◽  
Sensory Feedback ◽  
Sensory Input ◽  
Neural Circuits ◽  
Sensory Information ◽  
The Body ◽  
Feedback Delay ◽  
Run Off ◽  
Effects Of Feedback ◽  
The Brain

The emulation theory of representation is developed and explored as a framework that can revealingly synthesize a wide variety of representational functions of the brain. The framework is based on constructs from control theory (forward models) and signal processing (Kalman filters). The idea is that in addition to simply engaging with the body and environment, the brain constructs neural circuits that act as models of the body and environment. During overt sensorimotor engagement, these models are driven by efference copies in parallel with the body and environment, in order to provide expectations of the sensory feedback, and to enhance and process sensory information. These models can also be run off-line in order to produce imagery, estimate outcomes of different actions, and evaluate and develop motor plans. The framework is initially developed within the context of motor control, where it has been shown that inner models running in parallel with the body can reduce the effects of feedback delay problems. The same mechanisms can account for motor imagery as the off-line driving of the emulator via efference copies. The framework is extended to account for visual imagery as the off-line driving of an emulator of the motor-visual loop. I also show how such systems can provide for amodal spatial imagery. Perception, including visual perception, results from such models being used to form expectations of, and to interpret, sensory input. I close by briefly outlining other cognitive functions that might also be synthesized within this framework, including reasoning, theory of mind phenomena, and language.

scholarly journals Mimicry is associated with procedural learning, not social bonding, neural systems in autism

2020 ◽  
Author(s):  
Bahar Tunçgenç ◽  
Carolyn Koch ◽  
Amira Herstic ◽  
Inge-Marie Eigsti ◽  
Stewart Mostofsky
Keyword(s):  
Social Bonding ◽  
Brain Regions ◽  
Autism Spectrum ◽  
Skill Learning ◽  
Autism Spectrum Conditions ◽  
Neural Systems ◽  
Procedural Skill ◽  
Communication Difficulties ◽  
Learning Functions ◽  
The Brain

AbstractMimicry facilitates social bonding throughout the lifespan. Mimicry impairments in autism spectrum conditions (ASC) are widely reported, including differentiation of the brain networks associated with its social bonding and learning functions. This study examined associations between volumes of brain regions associated with social bonding versus procedural skill learning, and mimicry of gestures during a naturalistic interaction in ASC and neurotypical (NT) children. Consistent with predictions, results revealed reduced mimicry in ASC relative to the NT children. Mimicry frequency was negatively associated with autism symptom severity. Mimicry was predicted predominantly by the volume of procedural skill learning regions in ASC, and by bonding regions in NT. Further, bonding regions contributed significantly less to mimicry in ASC than in NT, while the contribution of learning regions was not different across groups. These findings suggest that associating mimicry with skill learning, rather than social bonding, may partially explain observed communication difficulties in ASC.

scholarly journals Recovery of Brain in Chick Embryos by Growing Second Heart and Brain

2019 ◽  
Vol 7 (18) ◽  
pp. 3085-3089
Author(s):  
Massimo Fioranelli ◽  
Alireza Sepehri ◽  
Maria Grazia Roccia ◽  
Cota Linda ◽  
Chiara Rossi ◽  
...  
Keyword(s):  
Subventricular Zone ◽  
Blood Cells ◽  
Neural Circuits ◽  
Circulatory System ◽  
Egg Cell ◽  
Chick Embryos ◽  
Injured Brain ◽  
Embryo Heart ◽  
Healthy Part ◽  
The Brain

To recover chick embryos damaged the brain, two methods are presented. In both of them, somatic cells of an embryo introduced into an egg cell and an embryo have emerged. In one method, injured a part of the brain in the head of an embryo is replaced with a healthy part of the brain. In the second method, the heart of brain embryo dead is transplanted with the embryo heart. In this mechanism, new blood cells are emerged in the bone marrow and transmit information of transplantation to subventricular zone (SVZ) of the brain through the circulatory system. Then, SVZ produces new neural stem cells by a subsequent dividing into neurons. These neurons produce new neural circuits within the brain and recover the injured brain. To examine the model, two hearts of two embryos are connected, and their effects on neural circuits are observed.  

scholarly journals The Retina: A Window into the Brain

Cells ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 3269
Author(s):  
Maurice Ptito ◽  
Maxime Bleau ◽  
Joseph Bouskila
Keyword(s):  
Sensory Systems ◽  
The Brain

In the course of evolution, animals have obtained the capacity to perceive and encode their environment via the development of sensory systems such as touch, olfaction, audition, and vision [...]

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