scholarly journals Vision and the representation of the surroundings in spatial memory

2011 ◽  
Vol 366 (1564) ◽  
pp. 596-610 ◽  
Author(s):  
Benjamin W. Tatler ◽  
Michael F. Land
Keyword(s):  
Spatial Memory ◽  
Visual Environment ◽  
Coding Scheme ◽  
Perceptual Stability ◽  
The World ◽  
Scene Viewing ◽  
Memory Representations ◽  
The Brain ◽  
Allocentric Representations ◽  
And Task

One of the paradoxes of vision is that the world as it appears to us and the image on the retina at any moment are not much like each other. The visual world seems to be extensive and continuous across time. However, the manner in which we sample the visual environment is neither extensive nor continuous. How does the brain reconcile these differences? Here, we consider existing evidence from both static and dynamic viewing paradigms together with the logical requirements of any representational scheme that would be able to support active behaviour. While static scene viewing paradigms favour extensive, but perhaps abstracted, memory representations, dynamic settings suggest sparser and task-selective representation. We suggest that in dynamic settings where movement within extended environments is required to complete a task, the combination of visual input, egocentric and allocentric representations work together to allow efficient behaviour. The egocentric model serves as a coding scheme in which actions can be planned, but also offers a potential means of providing the perceptual stability that we experience.

Multisensory Integration and the Perception of Self-Motion

2018 ◽  
Author(s):  
Kathleen E. Cullen
Keyword(s):  
Rotational Velocity ◽  
Sensory Information ◽  
Proprioceptive Information ◽  
Everyday Activities ◽  
Perceptual Stability ◽  
The World ◽  
Perception Of Self ◽  
Self Motion ◽  
The Brain ◽  
Vestibular Pathways

As we go about our everyday activities, our brain computes accurate estimates of both our motion relative to the world, and of our orientation relative to gravity. Essential to this computation is the information provided by the vestibular system; it detects the rotational velocity and linear acceleration of our heads relative to space, making a fundamental contribution to our perception of self-motion and spatial orientation. Additionally, in everyday life, our perception of self-motion depends on the integration of both vestibular and nonvestibular cues, including visual and proprioceptive information. Furthermore, the integration of motor-related information is also required for perceptual stability, so that the brain can distinguish whether the experienced sensory inflow was a result of active self-motion through the world or if instead self-motion that was externally generated. To date, understanding how the brain encodes and integrates sensory cues with motor signals for the perception of self-motion during natural behaviors remains a major goal in neuroscience. Recent experiments have (i) provided new insights into the neural code used to represent sensory information in vestibular pathways, (ii) established that vestibular pathways are inherently multimodal at the earliest stages of processing, and (iii) revealed that self-motion information processing is adjusted to meet the needs of specific tasks. Our current level of understanding of how the brain integrates sensory information and motor-related signals to encode self-motion and ensure perceptual stability during everyday activities is reviewed.

scholarly journals A functional division of Drosophila sweet taste neurons that is value-based and task-specific

2022 ◽  
Vol 119 (3) ◽  
pp. e2110158119
Author(s):  
Hsueh-Ling Chen ◽  
Dorsa Motevalli ◽  
Ulrich Stern ◽  
Chung-Hui Yang
Keyword(s):  
Sweet Taste ◽  
Egg Laying ◽  
Taste System ◽  
Conventional View ◽  
Coding Scheme ◽  
Sensory Pathway ◽  
The Brain ◽  
Is Value ◽  
Lateral Protocerebrum ◽  
And Task

Sucrose is an attractive feeding substance and a positive reinforcer for Drosophila. But Drosophila females have been shown to robustly reject a sucrose-containing option for egg-laying when given a choice between a plain and a sucrose-containing option in specific contexts. How the sweet taste system of Drosophila promotes context-dependent devaluation of an egg-laying option that contains sucrose, an otherwise highly appetitive tastant, is unknown. Here, we report that devaluation of sweetness/sucrose for egg-laying is executed by a sensory pathway recruited specifically by the sweet neurons on the legs of Drosophila. First, silencing just the leg sweet neurons caused acceptance of the sucrose option in a sucrose versus plain decision, whereas expressing the channelrhodopsin CsChrimson in them caused rejection of a plain option that was “baited” with light over another that was not. Analogous bidirectional manipulations of other sweet neurons did not produce these effects. Second, circuit tracing revealed that the leg sweet neurons receive different presynaptic neuromodulations compared to some other sweet neurons and were the only ones with postsynaptic partners that projected prominently to the superior lateral protocerebrum (SLP) in the brain. Third, silencing one specific SLP-projecting postsynaptic partner of the leg sweet neurons reduced sucrose rejection, whereas expressing CsChrimson in it promoted rejection of a light-baited option during egg-laying. These results uncover that the Drosophila sweet taste system exhibits a functional division that is value-based and task-specific, challenging the conventional view that the system adheres to a simple labeled-line coding scheme.

scholarly journals Testing the precision of spatial memory representations using a change-detection task: Effects of viewpoint change

2020 ◽  
Author(s):  
Edward Heywood-Everett ◽  
Daniel H Baker ◽  
Tom Hartley
Keyword(s):  
Spatial Memory ◽  
Change Detection ◽  
Spatial Information ◽  
Linear Increase ◽  
Spatial Knowledge ◽  
Task Demands ◽  
Task Effects ◽  
Viewpoint Change ◽  
Memory Representations ◽  
The Brain

There are at least two distinct ways in which the brain encodes spatial information: in egocentric representations locations are encoded relative to the observer, whereas in allocentric representations locations are encoded relative to the environment. Both inform spatial memory, but the extent to which they influence behaviour varies depending on the task. In the present study, two preregistered experiments used a psychophysical approach to measure the precision of spatial memory while varying ego- and allocentric task demands. Participants were asked to detect the changed location of one of four objects when seen from a new viewpoint (rotated by 0°, 5°, 15°, 45° or 135°). Experiment 1 used a Same/Different task and Experiment 2 used a 2AFC task. Psychophysical thresholds were calculated, showing that in both experiments, spatial change detection thresholds showed a monotonic but non-linear increase as viewpoint change increased. This was consistent with a preregistered model including distinct parameters corresponding to egocentric and allocentric contributions that change lawfully as a function of viewpoint shift. Our results provide a clearer understanding of how underlying memory representations interact to inform our spatial knowledge of the environment.

Pelvic schwannoma

GYNECOLOGY ◽  
2020 ◽  
Vol 22 (5) ◽  
pp. 84-86
Author(s):  
Sergei P. Sinchikhin ◽  
Sarkis G. Magakyan ◽  
Oganes G. Magakyan
Keyword(s):  
Auditory Nerve ◽  
World Literature ◽  
Morphological Study ◽  
Clinical Observation ◽  
Nerve Trunk ◽  
Practical Case ◽  
Surgical Volume ◽  
The World ◽  
Brain And Spinal Cord ◽  
The Brain

Relevance.A neoplasm originated from the myelonic sheath of the nerve trunk is called neurinoma or neurilemmoma, neurinoma, schwannoglioma, schwannoma. This tumor can cause compression and dysfunction of adjacent tissues and organs. The most common are the auditory nerve neurinomas (1 case per 100 000 population per year), the brain and spinal cord neurinomas are rare. In the world literature, there is no information on the occurrences of this tumor in the pelvic region. Description.Presented below is a clinical observation of a 30-year-old patient who was scheduled for myomectomy. During laparoscopy, an unusual tumor of the small pelvis was found and radically removed. A morphological study allowed to identify the remote neoplasm as a neuroma. Conclusion.The presented practical case shows that any tumor can hide under a clinical mask of another disease. The qualification of the doctor performing laparoscopic myomectomy should be sufficient to carry out, if necessary, another surgical volume.

Consciousness, law of nature, and nomological determinism

2018 ◽  
Author(s):  
Xiaoyang Yu
Keyword(s):  
Free Will ◽  
Important Thing ◽  
Law Of Nature ◽  
The World ◽  
The Law ◽  
The Brain

Nomological determinism does not mean everything is predictable. It just means everything follows the law of nature. And the most important thing Is that the brain and consciousness follow the law of nature. In other words, there is no free will. Without life, brain and consciousness, the world follows law of nature, that is clear. The life and brain are also part of nature, and they follow the law of nature. This is due to scientific findings. There are not enough scientific findings for consciousness yet. But I think that the consciousness is a nature phenomenon, and it also follows the law of nature.

Exploring the abnormal signal transduction mediated internet addiction and gaming disorders

2020 ◽  
Vol 15 ◽  
Author(s):  
Bhumika Chauhan ◽  
Sisir Nandi
Keyword(s):  
Signal Transduction ◽  
Internet Addiction ◽  
Internet Gaming Disorder ◽  
Online Data ◽  
Abnormal Signal ◽  
Internet Gaming ◽  
The World ◽  
Loss Of Appetite ◽  
Sleeping Disorder ◽  
The Brain

: The world is connected by the internet. It is very useful because we use Google to find out any new topic, to search new places, to quest updated research, and to get knowledge for learnng. The person around the world can communicate with each other through the Google video conference talk. Internet is frequently used in smartphones, laptops, desktop, and tablet. Excessive affinity towards internet-based online data collection, downloading pictures, videos, cyber relationships, and social media may produce addiction disorders followed by different symptoms such as behaviors change, mind disturbance, depression, anxiety, loss of appetite hyperactivity, sleeping disorder, headache, visual fatigueness, trafficking of memory, attention-deficit, loss of efficiency in work and social detachment which may be caused by an imbalance of neurotransmitters. This is very difficult to control because of abnormal signal transduction in the brain. The present study is an attempt to discuss internet addiction disorder (IAD), internet gaming disorder (IGD), and give awareness to society to get rid of this addiction.

scholarly journals Measuring Caregiver Person-Centered Communication for Persons With Dementia via Video Observations

2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 152-152
Author(s):  
Ying-Ling Jao ◽  
Carissa Coleman ◽  
Kristine Williams ◽  
Diane Berish ◽  
Wen Liu ◽  
...  
Keyword(s):  
Sequential Analysis ◽  
Controlled Trial ◽  
Verbal Communication ◽  
Rater Reliability ◽  
Coding Scheme ◽  
Video Observations ◽  
Interactive Nature ◽  
The Impact ◽  
Mealtime Interactions ◽  
And Task

Abstract Communication is fundamental for daily care activities in nursing homes (NHs). Second-by-second behavioral coding of video observations is an ideal approach to examine the interactive nature of communication but requires a reliable coding scheme. Recent studies have adapted the Peron-Centered Behavioral Inventory (PCBI) and Task-Centered Behavioral Inventory (TCBI) to analyze caregiver communication during mealtime interactions, but their use for coding general daily caregiving activities has not been widely evaluated. This pilot study adapted the PCBI and TCBI of video observations and determined their inter-rater reliability for measuring caregiver verbal communication with persons with dementia (PwD). We analyzed videos from a randomized controlled trial of an intervention to improve caregiver communication in NHs. We selected one 1-minute segment from 12 videos that included interactions of caregiver-resident dyads. One research assistant transcribed caregivers’ verbal communication and segmented the communication into utterances. Two other research assistants independently coded each utterance using the adapted PCBI and TCBI. The coding scheme was expanded by modifying the existing operational definitions, adding three new codes, and developing a coding decision guide. Residents were Caucasian (100%), mean age 86 years with dementia and resistive behaviors. The adapted PCBI and TCBI had an inter-rater reliability of Kappa=0.656 (p<.001) across the 12 videos. Overall, our adapted PCBI and TCBI showed substantial inter-rater reliability. The results support the use of our adapted PCBI and TCBI to distinguish between person-centered and task-centered communication in video observations, which, in turn, allows for sequential analysis to examine the impact of caregiver communication on PwD.

scholarly journals Extending the extended consciousness debate: perception, imagination, and the common kind assumption

2021 ◽  
Author(s):  
James Deery
Keyword(s):  
Perceptual Experience ◽  
Phenomenal Consciousness ◽  
Psychological Theory ◽  
Predictive Processing ◽  
Mental Event ◽  
The World ◽  
Predictive Approach ◽  
The Common ◽  
The Relationship ◽  
The Brain

AbstractFor some, the states and processes involved in the realisation of phenomenal consciousness are not confined to within the organismic boundaries of the experiencing subject. Instead, the sub-personal basis of perceptual experience can, and does, extend beyond the brain and body to implicate environmental elements through one’s interaction with the world. These claims are met by proponents of predictive processing, who propose that perception and imagination should be understood as a product of the same internal mechanisms. On this view, as visually imagining is not considered to be world-involving, it is assumed that world-involvement must not be essential for perception, and thus internalism about the sub-personal basis is true. However, the argument for internalism from the unity of perception and imagination relies for its strength on a questionable conception of the relationship between the two experiential states. I argue that proponents of the predictive approach are guilty of harbouring an implicit commitment to the common kind assumption which does not follow trivially from their framework. That is, the assumption that perception and imagination are of the same fundamental kind of mental event. I will argue that there are plausible alternative ways of conceiving of this relationship without drawing internalist metaphysical conclusions from their psychological theory. Thus, the internalist owes the debate clarification of this relationship and further argumentation to secure their position.

The brain as a mediator of the mind and the world

Cortex ◽  
2009 ◽  
Vol 45 (7) ◽  
pp. 904-905
Author(s):  
Zhicheng Lin
Keyword(s):  
The World ◽  
The Mind ◽  
The Brain

Intact Priming for Novel Perceptual Representations in Amnesia

1997 ◽  
Vol 9 (6) ◽  
pp. 699-713 ◽  
Author(s):  
Stephan B. Hamann ◽  
Larry R. Squire
Keyword(s):  
Recognition Memory ◽  
Declarative Memory ◽  
Brain Structures ◽  
Perceptual Identification ◽  
Single Exposure ◽  
Memory Representations ◽  
Perceptual Representations ◽  
The Creation ◽  
And Control ◽  
The Brain

Recent studies have challenged the notion that priming for ostensibly novel stimuli such as pseudowords (REAB) reflects the creation of new representations. Priming for such stimuli could instead reflect the activation of familiar memory representations that are orthographically similar (READ) and/or the activation of subparts of stimuli (RE, EX, AR), which are familar because they occur commonly in English. We addressed this issue in three experiments that assessed perceptual identification priming and recognition memory for novel and familiar letter strings in amnesic patients and control subjects. Priming for words, pseudowords, and orthographically illegal nonwords was fully intact in the amnesic patients following a single exposure, whereas recognition memory was impaired for the same items. Thus, priming can occur for stimuli that are unlikely to have preexisting representations. Words and pseudowords exhibited twice as much priming as illegal nonwords, suggesting that activation may contribute to priming for words and wordlike stimuli. Additional results showed that priming for illegal nonwords resulted from the formation of new perceptual associations among the component letters of each nonword rather than the activation of individual letter representations. In summary, the results demonstrate that priming following a single exposure can depend on the creation of new perceptual representations and that such priming is independent of the brain structures essential for declarative memory.

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