scholarly journals Developmental plasticity of texture discrimination following early vision loss in the marsupial Monodelphis domestica

2021 ◽  
Vol 224 (9) ◽  
Author(s):  
Deepa L. Ramamurthy ◽  
Heather K. Dodson ◽  
Leah A. Krubitzer
Keyword(s):  
Developmental Plasticity ◽  
Behavioral Plasticity ◽  
Vision Loss ◽  
Functional Organization ◽  
Sensory Information ◽  
Monodelphis Domestica ◽  
Behavioral Strategies ◽  
Discrimination Accuracy ◽  
Texture Discrimination ◽  
Tactile Cues

ABSTRACT Behavioral strategies that depend on sensory information are not immutable; rather they can be shaped by the specific sensory context in which animals develop. This behavioral plasticity depends on the remarkable capacity of the brain to reorganize in response to alterations in the sensory environment, particularly when changes in sensory input occur at an early age. To study this phenomenon, we utilize the short-tailed opossum, a marsupial that has been a valuable animal model to study developmental plasticity due to the extremely immature state of its nervous system at birth. Previous studies in opossums have demonstrated that removal of retinal inputs early in development results in profound alterations to cortical connectivity and functional organization of visual and somatosensory cortex; however, behavioral consequences of this plasticity are not well understood. We trained early blind and sighted control opossums to perform a two-alternative forced choice texture discrimination task. Whisker trimming caused an acute deficit in discrimination accuracy for both groups, indicating the use of a primarily whisker-based strategy to guide choices based on tactile cues. Mystacial whiskers were important for performance in both groups; however, genal whiskers only contributed to behavioral performance in early blind animals. Early blind opossums significantly outperformed their sighted counterparts in discrimination accuracy, with discrimination thresholds that were lower by ∼75 μm. Our results support behavioral compensation following early blindness using tactile inputs, especially the whisker system.

scholarly journals Developmental plasticity of texture discrimination following early vision loss in the marsupial Monodelphis domestica

2020 ◽  
Author(s):  
Deepa L. Ramamurthy ◽  
Heather K. Dodson ◽  
Leah A. Krubitzer
Keyword(s):  
Developmental Plasticity ◽  
Behavioral Plasticity ◽  
Vision Loss ◽  
Functional Organization ◽  
Sensory Information ◽  
Monodelphis Domestica ◽  
Body Parts ◽  
Behavioral Strategies ◽  
Discrimination Accuracy ◽  
Texture Discrimination

ABSTRACTBehavioral strategies that depend on sensory information are not immutable; rather they can be shaped by the specific sensory context in which animals develop. This behavioral plasticity depends on the remarkable capacity for the brain to reorganize in response to alterations in the sensory environment, particularly when changes in sensory input occur at an early age. To study this phenomenon, we utilize the short-tailed opossum, a marsupial that has been a valuable animal model to study developmental plasticity due to the extremely immature state of its nervous system at birth. Previous studies in opossums have demonstrated that removal of retinal inputs early in development results in profound alterations to cortical connectivity and functional organization of visual and somatosensory cortex; however, behavioral consequences of this plasticity are not well understood. We trained early blind (EB) and sighted control (SC) opossums to perform a two-alternative forced choice texture discrimination task. Whisker trimming caused an acute deficit in discrimination accuracy for both EB and SC animals indicating that they primarily used a whisker-based strategy to guide choices based on tactile cues – though performance recovered in days, suggesting a shift to the use of other body parts when whiskers were absent. Mystacial whiskers were important for performance in both groups; however, genal whiskers only contributed to performance in EB animals. EB opossums significantly outperformed SC opossums in discrimination accuracy, being more sensitive to textural differences by ~75 μm smaller. Our results support behavioral compensation following early blindness using tactile inputs, especially the whisker system.

Optical imaging of orientation and ocular dominance maps in area 17 of cats with convergent strabismus

2002 ◽  
Vol 19 (1) ◽  
pp. 39-49 ◽  
Author(s):  
RALF ENGELMANN ◽  
JOHN M. CROOK ◽  
SIEGRID LÖWEL
Keyword(s):  
Optical Imaging ◽  
Developmental Plasticity ◽  
Functional Organization ◽  
Ocular Dominance ◽  
Gene Pools ◽  
Area 17 ◽  
Intrinsic Signals ◽  
Functional Layout ◽  
Adult Cats ◽  
And Control

Strabismus (or squint) is both a well-established model for developmental plasticity of the brain and a frequent clinical symptom. While the layout and topographic relationship of functional domains in area 17 of divergently squinting cats has been analyzed extensively in recent years (e.g. Löwel et al., 1998), functional maps in convergently squinting animals have so far not been visualized with comparable detail. We have therefore investigated the functional organization of area 17 in adult cats with a surgically induced convergent squint angle. In these animals, visual acuity was determined by both behavioral tests and recordings of visual evoked potentials, and animals with comparable acuities in both eyes were selected for further experiments. The functional layout of area 17 was visualized using optical imaging of intrinsic signals. Monocular iso-orientation domains had a patchy appearance and their layout was different for left and right eye stimulation, so that segregated ocular dominance domains could be visualized. Iso-orientation domains exhibited a pinwheel-like organization, as previously described for normal and divergently squinting cats. Mean pinwheel density was the same in the experimental and control animals (3.4 pinwheel centers per mm2 cortical surface), but significantly (P < 0.00001) higher than that reported previously for normal and divergently squinting cats (2.7/mm2). A comparison of orientation with ocular dominance maps revealed that iso-orientation domains were continuous across the borders of ocular dominance domains and tended to intersect these borders at steep angles. However, in contrast to previous reports in normally raised cats, orientation pinwheel centers showed no consistent topographical relationship to the peaks of ocular dominance domains. Taken together, these observations indicate an overall similarity between the functional layout of orientation and ocular dominance maps in area 17 of convergently and divergently squinting cats. The higher pinwheel densities compared with previous reports suggest that animals from different gene pools might generally differ in this parameter and therefore also in the space constants of their cortical orientation maps.

scholarly journals The restless brain: how intrinsic activity organizes brain function

2015 ◽  
Vol 370 (1668) ◽  
pp. 20140172 ◽  
Author(s):  
Marcus E. Raichle
Keyword(s):  
Brain Function ◽  
Functional Organization ◽  
Sensory Information ◽  
Intrinsic Activity ◽  
Systems Neuroscience ◽  
Brain Functions ◽  
Molecular Neuroscience ◽  
Constant State ◽  
Health And Disease ◽  
The Brain

Traditionally studies of brain function have focused on task-evoked responses. By their very nature such experiments tacitly encourage a reflexive view of brain function. While such an approach has been remarkably productive at all levels of neuroscience, it ignores the alternative possibility that brain functions are mainly intrinsic and ongoing, involving information processing for interpreting, responding to and predicting environmental demands. I suggest that the latter view best captures the essence of brain function, a position that accords well with the allocation of the brain's energy resources, its limited access to sensory information and a dynamic, intrinsic functional organization. The nature of this intrinsic activity, which exhibits a surprising level of organization with dimensions of both space and time, is revealed in the ongoing activity of the brain and its metabolism. As we look to the future, understanding the nature of this intrinsic activity will require integrating knowledge from cognitive and systems neuroscience with cellular and molecular neuroscience where ion channels, receptors, components of signal transduction and metabolic pathways are all in a constant state of flux. The reward for doing so will be a much better understanding of human behaviour in health and disease.

scholarly journals Detour learning ability and the effect of novel sensory cues on learning in Australian bull ants, Myrmecia midas

2021 ◽  
Author(s):  
Muzahid Islam ◽  
Sudhakar Deeti ◽  
Zakia Mahmudah ◽  
J. Frances Kamhi ◽  
Ken Cheng
Keyword(s):  
Animal Cognition ◽  
Sensory Information ◽  
Learning Ability ◽  
Visual Environment ◽  
Sensory Cues ◽  
Complex Environment ◽  
Physical Barriers ◽  
Tactile Cues ◽  
Detour Learning ◽  
Do So

ABSTRACTMany animals navigate in a structurally complex environment which requires them to detour around physical barriers that they encounter. While many studies in animal cognition suggest that they are able to adeptly avoid obstacles, it is unclear whether a new route is learned to navigate around these barriers and, if so, what sensory information may be used to do so. We investigated detour learning ability in the Australian bull ant, Myrmecia midas, which primarily uses visual landmarks to navigate. We first placed a barrier on the ants’ natural path of their foraging tree. Initially, 46% of foragers were unsuccessful in detouring the obstacle. In subsequent trips, the ants became more successful and established a new route. We observed up to eight successful foraging trips detouring around the barrier. When we subsequently changed the position of the barrier, made a new gap in the middle of the obstacle, or removed the barrier altogether, ants mostly maintained their learned motor routine, detouring with a similar path as before, suggesting that foragers were not relying on barrier cues and therefore learned a new route around the obstacle. In additional trials, when foragers encountered new olfactory or tactile cues, or the visual environment was blocked, their navigation was profoundly disrupted. These results suggest that changing sensory information, even in modalities that foragers do not usually need for navigation, drastically affects the foragers’ ability to successful navigate.Subject CategoryNeuroscience and Cognition

scholarly journals Sensory-Motor Modulations of EEG Event-Related Potentials Reflect Walking-Related Macro-Affordances

2021 ◽  
Vol 11 (11) ◽  
pp. 1506
Author(s):  
Annalisa Tosoni ◽  
Emanuele Cosimo Altomare ◽  
Marcella Brunetti ◽  
Pierpaolo Croce ◽  
Filippo Zappasodi ◽  
...  
Keyword(s):  
Large Scale ◽  
Functional Organization ◽  
Sensory Information ◽  
Event Related Potentials ◽  
Stimulus Presentation ◽  
Fundamental Principle ◽  
Facilitation Effect ◽  
Extrapersonal Space ◽  
Sensory Motor ◽  
Related Potentials

One fundamental principle of the brain functional organization is the elaboration of sensory information for the specification of action plans that are most appropriate for interaction with the environment. Using an incidental go/no-go priming paradigm, we have previously shown a facilitation effect for the execution of a walking-related action in response to far vs. near objects/locations in the extrapersonal space, and this effect has been called “macro-affordance” to reflect the role of locomotion in the coverage of extrapersonal distance. Here, we investigated the neurophysiological underpinnings of such an effect by recording scalp electroencephalography (EEG) from 30 human participants during the same paradigm. The results of a whole-brain analysis indicated a significant modulation of the event-related potentials (ERPs) both during prime and target stimulus presentation. Specifically, consistent with a mechanism of action anticipation and automatic activation of affordances, a stronger ERP was observed in response to prime images framing the environment from a far vs. near distance, and this modulation was localized in dorso-medial motor regions. In addition, an inversion of polarity for far vs. near conditions was observed during the subsequent target period in dorso-medial parietal regions associated with spatially directed foot-related actions. These findings were interpreted within the framework of embodied models of brain functioning as arising from a mechanism of motor-anticipation and subsequent prediction error which was guided by the preferential affordance relationship between the distant large-scale environment and locomotion. More in general, our findings reveal a sensory-motor mechanism for the processing of walking-related environmental affordances.

scholarly journals Neuropeptides and Behaviors: How Small Peptides Regulate Nervous System Function and Behavioral Outputs

2021 ◽  
Vol 14 ◽  
Author(s):  
Umer Saleem Bhat ◽  
Navneet Shahi ◽  
Siju Surendran ◽  
Kavita Babu
Keyword(s):  
Nervous System ◽  
Behavioral Plasticity ◽  
Environmental Changes ◽  
Sensory Information ◽  
Synaptic Activity ◽  
Small Peptides ◽  
C Elegans ◽  
Wide Range ◽  
Nervous System Function ◽  
Insight Into

One of the reasons that most multicellular animals survive and thrive is because of the adaptable and plastic nature of their nervous systems. For an organism to survive, it is essential for the animal to respond and adapt to environmental changes. This is achieved by sensing external cues and translating them into behaviors through changes in synaptic activity. The nervous system plays a crucial role in constantly evaluating environmental cues and allowing for behavioral plasticity in the organism. Multiple neurotransmitters and neuropeptides have been implicated as key players for integrating sensory information to produce the desired output. Because of its simple nervous system and well-established neuronal connectome, C. elegans acts as an excellent model to understand the mechanisms underlying behavioral plasticity. Here, we critically review how neuropeptides modulate a wide range of behaviors by allowing for changes in neuronal and synaptic signaling. This review will have a specific focus on feeding, mating, sleep, addiction, learning and locomotory behaviors in C. elegans. With a view to understand evolutionary relationships, we explore the functions and associated pathophysiology of C. elegans neuropeptides that are conserved across different phyla. Further, we discuss the mechanisms of neuropeptidergic signaling and how these signals are regulated in different behaviors. Finally, we attempt to provide insight into developing potential therapeutics for neuropeptide-related disorders.

scholarly journals Cortical plasticity following stripe rearing in the marsupialMonodelphis domestica: neural response properties of V1

2017 ◽  
Vol 117 (2) ◽  
pp. 566-581 ◽  
Author(s):  
James C. Dooley ◽  
Michaela S. Donaldson ◽  
Leah A. Krubitzer
Keyword(s):  
Visual System ◽  
Cortical Neurons ◽  
Functional Organization ◽  
Sensory Experience ◽  
Monodelphis Domestica ◽  
Visual Environment ◽  
Visual Response ◽  
Response Properties ◽  
Dependent Plasticity ◽  
Marsupial Species

The functional organization of the primary visual area (V1) and the importance of sensory experience in its normal development have been well documented in eutherian mammals. However, very few studies have investigated the response properties of V1 neurons in another large class of mammals, or whether sensory experience plays a role in shaping their response properties. Thus we reared opossums ( Monodelphis domestica) in normal and vertically striped cages until they reached adulthood. They were then anesthetized using urethane, and electrophysiological techniques were used to examine neuronal responses to different orientations, spatial and temporal frequencies, and contrast levels. For normal opossums, we observed responses to the temporal and spatial characteristics of the stimulus to be similar to those described in small, nocturnal, eutherian mammals such as rats and mice; neurons in V1 responded maximally to stimuli at 0.09 cycles per degree and 2.12 cycles per second. Unlike other eutherians, but similar to other marsupials investigated, only 40% of the neurons were orientation selective. In stripe-reared animals, neurons were significantly more likely to respond to vertical stimuli at a wider range of spatial frequencies, and were more sensitive to gratings at lower contrast values compared with normal animals. These results are the first to demonstrate experience-dependent plasticity in the visual system of a marsupial species. Thus the ability of cortical neurons to alter their properties based on the dynamics of the visual environment predates the emergence of eutherian mammals and was likely present in our earliest mammalian ancestors.NEW & NOTEWORTHY These results are the first description of visual response properties of the most commonly studied marsupial model organism, the short-tailed opossum ( Monodelphis domestica). Further, these results are the first to demonstrate experience-dependent plasticity in the visual system of a marsupial species. Thus the ability of cortical neurons to alter their properties based on the dynamics of the visual environment predates the emergence of eutherian mammals and was likely present in our earliest mammalian ancestors.

Proprioception From a Spinocerebellar Perspective

2001 ◽  
Vol 81 (2) ◽  
pp. 539-568 ◽  
Author(s):  
G. Bosco ◽  
R. E. Poppele
Keyword(s):  
Spinal Cord ◽  
Nervous System ◽  
Functional Organization ◽  
Body Position ◽  
Historical Context ◽  
Sensory Information ◽  
Functional Relationships ◽  
Central Neurons ◽  
Global Representation ◽  
Limb Kinematics

This review explores how proprioceptive sensory information is organized at spinal cord levels as it relates to a sense of body position and movement. The topic is considered in an historical context and develops a different framework that may be more in tune with current views of sensorimotor processing in other central nervous system structures. The dorsal spinocerebellar tract (DSCT) system is considered in detail as a model system that may be considered as an end point for the processing of proprioceptive sensory information in the spinal cord. An analysis of this system examines sensory processing at the lowest levels of synaptic connectivity with central neurons in the nervous system. The analysis leads to a framework for proprioception that involves a highly flexible network organization based in some way on whole limb kinematics. The functional organization underlying this framework originates with the biomechanical linkages in the limb that establish functional relationships among the limb segments. Afferent information from limb receptors is processed further through a distributed neural network in the spinal cord. The result is a global representation of hindlimb parameters rather than a muscle-by-muscle or joint-by-joint representation.

scholarly journals Memory of recent oxygen experience switches pheromone valence in Caenorhabditis elegans

2017 ◽  
Vol 114 (16) ◽  
pp. 4195-4200 ◽  
Author(s):  
Lorenz A. Fenk ◽  
Mario de Bono
Keyword(s):  
Caenorhabditis Elegans ◽  
Behavioral Plasticity ◽  
Prior Experience ◽  
Sensory Information ◽  
Dependent Manner ◽  
Oxygen Environment ◽  
C Elegans ◽  
Sustained Change ◽  
Context Dependent ◽  
Physiological Correlate

Animals adjust their behavioral priorities according to momentary needs and prior experience. We show that Caenorhabditis elegans changes how it processes sensory information according to the oxygen environment it experienced recently. C. elegans acclimated to 7% O2 are aroused by CO2 and repelled by pheromones that attract animals acclimated to 21% O2. This behavioral plasticity arises from prolonged activity differences in a circuit that continuously signals O2 levels. A sustained change in the activity of O2-sensing neurons reprograms the properties of their postsynaptic partners, the RMG hub interneurons. RMG is gap-junctionally coupled to the ASK and ADL pheromone sensors that respectively drive pheromone attraction and repulsion. Prior O2 experience has opposite effects on the pheromone responsiveness of these neurons. These circuit changes provide a physiological correlate of altered pheromone valence. Our results suggest C. elegans stores a memory of recent O2 experience in the RMG circuit and illustrate how a circuit is flexibly sculpted to guide behavioral decisions in a context-dependent manner.

Behavioral and Developmental Plasticity of Buoyancy in the Longnose, Rhinichthys cataractae, and Blacknose, R. atratulus (Cyprinidae) Dace

1974 ◽  
Vol 31 (1) ◽  
pp. 35-41 ◽  
Author(s):  
John H. Gee
Keyword(s):  
Developmental Plasticity ◽  
Behavioral Plasticity ◽  
Adult Size ◽  
Volume Weight ◽  
Rhinichthys Cataractae ◽  
Negative Buoyancy

The hypothesis that developmental plasticity contributes to variation in swimbladder length, volume, weight of tissue, and buoyancy was examined in two species of dace. At both maximum and minimum buoyancy attained dace reared in still water to adult size possessed swimbladders of a greater length, volume, and weight of tissue than those reared in current. Such developmental plasticity affected the range over which buoyancy could be adjusted (behavioral plasticity). Those reared in still water attained a more buoyant condition than those reared in current while the latter attained a greater degree of negative buoyancy.

Sign in / Sign up

Export Citation Format

Share Document