The Role of Parts and Spatial Relations in Object Identification

Perception ◽  
1993 ◽  
Vol 22 (2) ◽  
pp. 229-248 ◽  
Author(s):  
Carolyn Backer Cave ◽  
Stephen M Kosslyn

An investigation of the role of parts and their spatial relations in object identification is reported. At the most general level, two important results were obtained. First, proper spatial relations among components of an object are critical for easy identification. When parts were scrambled on the page, naming times and error rates increased. And, second, the way an object is divided into parts (parsed) affects identification only under the most impoverished viewing conditions. When subjects had as little as 1 s (and sometimes as little as 200 ms) to view an object, the way objects were divided into parts had no effect on naming times or accuracy. There was no hint of an interaction between type of parse and how parts were arranged on the page. This pattern of effects supports theories that suggest that objects typically are recognized without being parsed into parts. The findings are in agreement with theories suggesting that object features (not specifically related to parts) are matched directly with such features stored in long-term memory, with the constraint that the features of a single object are seen from a single viewpoint.

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Hamish Patel ◽  
Reza Zamani

Abstract Long-term memories are thought to be stored in neurones and synapses that undergo physical changes, such as long-term potentiation (LTP), and these changes can be maintained for long periods of time. A candidate enzyme for the maintenance of LTP is protein kinase M zeta (PKMζ), a constitutively active protein kinase C isoform that is elevated during LTP and long-term memory maintenance. This paper reviews the evidence and controversies surrounding the role of PKMζ in the maintenance of long-term memory. PKMζ maintains synaptic potentiation by preventing AMPA receptor endocytosis and promoting stabilisation of dendritic spine growth. Inhibition of PKMζ, with zeta-inhibitory peptide (ZIP), can reverse LTP and impair established long-term memories. However, a deficit of memory retrieval cannot be ruled out. Furthermore, ZIP, and in high enough doses the control peptide scrambled ZIP, was recently shown to be neurotoxic, which may explain some of the effects of ZIP on memory impairment. PKMζ knockout mice show normal learning and memory. However, this is likely due to compensation by protein-kinase C iota/lambda (PKCι/λ), which is normally responsible for induction of LTP. It is not clear how, or if, this compensatory mechanism is activated under normal conditions. Future research should utilise inducible PKMζ knockdown in adult rodents to investigate whether PKMζ maintains memory in specific parts of the brain, or if it represents a global memory maintenance molecule. These insights may inform future therapeutic targets for disorders of memory loss.


2011 ◽  
Vol 35 (5) ◽  
pp. 613-628 ◽  
Author(s):  
Erik Gómez-Baggethun ◽  
Manuel Ruiz-Pérez

In the last decade a growing number of environmental scientists have advocated economic valuation of ecosystem services as a pragmatic short-term strategy to communicate the value of biodiversity in a language that reflects dominant political and economic views. This paper revisits the controversy on economic valuation of ecosystem services in the light of two aspects that are often neglected in ongoing debates. First, the role of the particular institutional setup in which environmental policy and governance is currently embedded in shaping valuation outcomes. Second, the broader economic and sociopolitical processes that have governed the expansion of pricing into previously non-marketed areas of the environment. Our analysis suggests that within the institutional setup and broader sociopolitical processes that have become prominent since the late 1980s economic valuation is likely to pave the way for the commodification of ecosystem services with potentially counterproductive effects in the long term for biodiversity conservation and equity of access to ecosystem services benefits.


2001 ◽  
Vol 69 (11) ◽  
pp. 6676-6682 ◽  
Author(s):  
Ben G. Marshall ◽  
Arun Wangoo ◽  
Peadar O'Gaora ◽  
H. Terry Cook ◽  
Rory J. Shaw ◽  
...  

ABSTRACT With a view to exploring the role of transforming growth factor β (TGF-β) during mycobacterial infection, recombinant clones of bacillus Calmette-Guérin (BCG) were engineered to express the natural antagonist of TGF-β, latency-activated peptide (LAP). Induction of TGF-β activity was reduced when macrophages were infected with BCG expressing the LAP construct (LAP-BCG). There was a significant reduction in the growth of LAP-BCG in comparison to that of control BCG following intravenous infection in a mouse model. The enhanced control of mycobacterial replication was associated with an increase in the production of gamma interferon by splenocytes challenged during the acute stage of infection but with a diminished recall response assessed after 13 weeks. Organ weight and hydroxyproline content, representing tissue pathology, were also lower in mice infected with LAP-BCG. The results are consistent with the hypothesis that TGF-β has a detrimental effect on mycobacterial immunity. While a reduction in TGF-β activity augments the initial response to BCG vaccination, early bacterial clearance may adversely affect the induction of a long-term memory response by LAP-BCG.


Author(s):  
D G Baitubayev ◽  
M D Baitubayeva

The work shows the role of the vegetative nervous system (VNS) in the functioning of long-term memory, identity mechanisms of long-term memory in the human evolutionary adaptation and substance dependence. It is shown that, depending on the substance of the body are states like pro- gressive adaptation, that the bodycondition, depending on the chemical and psychogenic psychoactive- factors state of the same circle. It proposed the creation of a branch of medicine that combines study of the dependence of the organism, both on the chemical and psychoactive psychogenic factors. Given the classification of psychoactive factors.Onomastics formulated definitions of terminology changes and additions to be used in a new branch of medicine. Proposed allocation of the International Classifica- tion of diseases separate chapter for the classification of states like progressive adaptation of the body depending on psychoactive factors.


2019 ◽  
pp. 201-232
Author(s):  
Ray Jackendoff ◽  
Jenny Audring

This chapter asks what is happening to linguistic representations during language use, and how representations are formed in the course of language acquisition. It is shown how Relational Morphology’s theory of representations can be directly embedded into models of processing and acquisition. Central is that the lexicon, complete with schemas and relational links, constitutes the long-term memory network that supports language production and comprehension. The chapter first discusses processing: the nature of working memory; promiscuous (opportunistic) processing; spreading activation; priming; probabilistic parsing; the balance between storage and computation in recognizing morphologically complex words; and the role of relational links and schemas in word retrieval. It then turns to acquisition, which is to be thought of as adding nodes and relational links to the lexical network. The general approach is based on the Propose but Verify procedure of Trueswell et al. (2013), plus conservative generalization, as in usage-based approaches.


2020 ◽  
pp. 0271678X2090835 ◽  
Author(s):  
Hélène Roumes ◽  
Ursule Dumont ◽  
Stéphane Sanchez ◽  
Leslie Mazuel ◽  
Jordy Blanc ◽  
...  

Hypoxic-ischemic (HI) encephalopathy remains a major cause of perinatal mortality and chronic disability in newborns worldwide (1–6 for 1000 births). The only current clinical treatment is hypothermia, which is efficient for less than 60% of babies. Mainly considered as a waste product in the past, lactate, in addition to glucose, is increasingly admitted as a supplementary fuel for neurons and, more recently, as a signaling molecule in the brain. Our aim was to investigate the neuroprotective effect of lactate in a neonatal (seven day old) rat model of hypoxia-ischemia. Pups received intra-peritoneal injection(s) of lactate (40 μmol). Size and apparent diffusion coefficients of brain lesions were assessed by magnetic resonance diffusion-weighted imaging. Oxiblot analyses and long-term behavioral studies were also conducted. A single lactate injection induced a 30% reduction in brain lesion volume, indicating a rapid and efficient neuroprotective effect. When oxamate, a lactate dehydrogenase inhibitor, was co-injected with lactate, the neuroprotection was completely abolished, highlighting the role of lactate metabolism in this protection. After three lactate injections (one per day), pups presented the smallest brain lesion volume and a complete recovery of neurological reflexes, sensorimotor capacities and long-term memory, demonstrating that lactate administration is a promising therapy for neonatal HI insult.


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