scholarly journals An individual differences approach to semantic cognition: Divergent effects of age on representation, retrieval and selection

2017 ◽  
Author(s):  
Paul Hoffman
Keyword(s):  
Older People ◽  
Executive Control ◽  
Semantic Information ◽  
Later Life ◽  
Semantic Knowledge ◽  
Semantic Representations ◽  
Semantic Cognition ◽  
Control Processes ◽  
The Relationship ◽  
Representation Of Knowledge

AbstractSemantic cognition refers to the appropriate use of acquired knowledge about the world. This requires representation of knowledge as well as control processes which ensure that currently-relevant aspects of knowledge are retrieved and selected. Although these abilities can be impaired selectively following brain damage, the relationship between them in healthy individuals is unclear. It is also commonly assumed that semantic cognition is preserved in later life, because older people have greater reserves of knowledge. However, this claim overlooks the possibility of decline in semantic control processes. Here, semantic cognition was assessed in 100 young and older adults. Despite having a broader knowledge base, older people showed specific impairments in semantic control, performing more poorly than young people when selecting among competing semantic representations. Conversely, they showed preserved controlled retrieval of less salient information from the semantic store. Breadth of semantic knowledge was positively correlated with controlled retrieval but was unrelated to semantic selection ability, which was instead correlated with non-semantic executive function. These findings indicate that three distinct elements contribute to semantic cognition: semantic representations that accumulate throughout the lifespan, processes for controlled retrieval of less salient semantic information, which appear age-invariant, and mechanisms for selecting task-relevant aspects of semantic knowledge, which decline with age and may relate more closely to domain-general executive control.

scholarly journals Validated measures of semantic knowledge and semantic control: Normative data from young and older adults for more than 300 semantic judgements

2021 ◽  
Author(s):  
Wei Wu ◽  
Paul Hoffman
Keyword(s):  
Normative Data ◽  
Semantic Processing ◽  
Feature Matching ◽  
Cognitive Architecture ◽  
Later Life ◽  
Semantic Knowledge ◽  
Matching Task ◽  
Large Set ◽  
Semantic Cognition ◽  
Control Processes

Recent studies suggest that knowledge representations and control processes are the two key components underpinning semantic cognition, and are also crucial indicators of the shifting cognitive architecture of semantics in later life. Although there are many standardized assessments that provide measures of the quantity of semantic knowledge participants possess, normative data for tasks that probe semantic control processes are not yet available. Here, we present normative data from more than 200 young and older participants on a large set of stimuli in two semantic tasks, which probe controlled semantic processing (feature-matching task) and semantic knowledge (synonym judgement task). We verify the validity of our norms by replicating established age- and psycholinguistic-property-related effects on semantic cognition. Specifically, we find that older people have more detailed semantic knowledge than young people but have less effective semantic control processes. We also obtain expected effects of word frequency and inter-item competition on performance. Parametrically varied difficulty levels are defined for half of the stimuli based on participants’ behavioral performance, allowing future studies to produce customized sets of experimental stimuli based on our norms. We provide all stimuli, data and code used for analysis, in the hope that they are useful to other researchers.

Semantic Cognition: Semantic Memory and Semantic Control

2021 ◽  
Author(s):  
Elizabeth Jefferies ◽  
Xiuyi Wang
Keyword(s):  
Semantic Memory ◽  
Semantic Processing ◽  
Inferior Frontal Gyrus ◽  
Semantic Knowledge ◽  
Human Cognition ◽  
Factual Knowledge ◽  
Conceptual Representations ◽  
Semantic Cognition ◽  
Control Processes ◽  
Functional Features

Semantic processing is a defining feature of human cognition, central not only to language, but also to object recognition, the generation of appropriate actions, and the capacity to use knowledge in reasoning, planning, and problem-solving. Semantic memory refers to our repository of conceptual or factual knowledge about the world. This semantic knowledge base is typically viewed as including “general knowledge” as well as schematic representations of objects and events distilled from multiple experiences and retrieved independently from their original spatial or temporal context. Semantic cognition refers to our ability to flexibly use this knowledge to produce appropriate thoughts and behaviors. Semantic cognition includes at least two interactive components: a long-term store of semantic knowledge and semantic control processes, each supported by a different network. Conceptual representations are organized according to the semantic relationships between items, with different theories proposing different key organizational principles, including sensory versus functional features, domain-specific theory, embodied distributed concepts, and hub-and-spoke theory, in which distributed features are integrated within a heteromodal hub in the anterior temporal lobes. The activity within the network for semantic representation must often be controlled to ensure that the system generates representations and inferences that are suited to the immediate task or context. Semantic control is thought to include both controlled retrieval processes, in which knowledge relevant to the goal or context is accessed in a top-down manner when automatic retrieval is insufficient for the task, and post-retrieval selection to resolve competition between simultaneously active representations. Control of semantic retrieval is supported by a strongly left-lateralized brain network, which partially overlaps with the bilateral network that supports domain-general control, but extends beyond these sites to include regions not typically associated with executive control, including anterior inferior frontal gyrus and posterior middle temporal gyrus. The interaction of semantic control processes with conceptual representations allows meaningful thoughts and behavior to emerge, even when the context requires non-dominant features of the concept to be brought to the fore.

The interplay between control processes and feature relevance: Evidence from dual-task methodology

2019 ◽  
Vol 73 (3) ◽  
pp. 384-395
Author(s):  
Maria Montefinese ◽  
Glyn Hallam ◽  
Hannah Elizabeth Thompson ◽  
Elizabeth Jefferies
Keyword(s):  
Divided Attention ◽  
Dual Task ◽  
Conceptual Knowledge ◽  
Semantic Representation ◽  
Semantic Knowledge ◽  
Semantic Retrieval ◽  
Semantic Cognition ◽  
Control Processes ◽  
And Control ◽  
Healthy Participants

Neuropsychological studies suggest a distinction between (a) semantic knowledge and (b) control processes that shape the retrieval of conceptual information to suit the task or context. These aspects of semantic cognition are specifically impaired in patients with semantic dementia and semantic aphasia, respectively. However, interactions between the structure of knowledge and control processes that are expected during semantic retrieval have not been fully characterised. In particular, domain-general executive resources may not have equal relevance for the capacity to promote weak yet task relevant features (i.e., “controlled retrieval) and to ignore or suppress distracting information (i.e., “selection”). Here, using a feature selection task, we tested the contribution of featural relevance to semantic performance in healthy participants under conditions of divided attention. Healthy participants showed greater dual-task disruption as the relevance value of the distractor feature linearly increased, supporting the emerging view that semantic relevance is one of the organising principles of the structure of semantic representation. Moreover, word frequency, and inter-correlational strength affected overall performance, but they did not show an interaction with dual-task conditions. These results suggest that domain-general control processes, disrupted by divided attention, are more important to the capacity to efficiently avoid distracting information during semantic decision-making than to the promotion of weak target features. The present study therefore provides novel information about the nature of the interaction between structured conceptual knowledge and control processes that support the retrieval of appropriate information and relates these results to a new theoretical framework, termed controlled semantic cognition.

The mobilities of care in later life: exploring the relationship between caring and mobility in the lives of older people

2020 ◽  
pp. 1-22
Author(s):  
Karen Croucher ◽  
Rose Gilroy ◽  
Mark Bevan ◽  
Katia Attuyer
Keyword(s):  
Longitudinal Study ◽  
Older People ◽  
Age Groups ◽  
Later Life ◽  
Life Transitions ◽  
The North ◽  
Care And Support ◽  
Younger Age ◽  
Per Se ◽  
The Relationship

Abstract There has been a renewed call for a revaluing of informal caring in order to counter the way that caring is undervalued, taken for granted and invisible. Travel is one area where a detailed critique of this issue has emerged with the concept of ‘mobility of care’, however, this concept has only been applied in relation to younger age groups, and our understanding of mobilities of care in later life remains underdeveloped. By ‘mobilities of care’ we mean journeys made for the purpose of giving and receiving informal care and support. This paper draws on the mobility narratives of 99 older people (aged 55 and above) living in three locations in the North of England who participated in a two-year qualitative longitudinal study that explored the inter-play between mobility, wellbeing and life transitions. We focused on the experience of managing life transitions rather than assume that chronology per se determines wellbeing. Narratives of ageing emphasise the importance of getting out and about, and being socially connected active citizens. Our study demonstrates that for many older people getting out and about is not for leisure or utility purposes but to give support and care. As such, these journeys have a particular significance in the lives of older people and in the construction of roles, meaning and identity in later life.

scholarly journals The interplay between semantic control processes and feature relevance: Evidence from dual task methodology

2018 ◽  
Author(s):  
Maria Montefinese ◽  
Glyn Hallam ◽  
Hannah Thompson ◽  
Beth Jefferies
Keyword(s):  
Divided Attention ◽  
Dual Task ◽  
Conceptual Knowledge ◽  
Semantic Representation ◽  
Semantic Knowledge ◽  
Semantic Retrieval ◽  
Semantic Cognition ◽  
Control Processes ◽  
And Control ◽  
Healthy Participants

Neuropsychological studies suggest a distinction between (i) semantic knowledge and (ii) control processes that shape the retrieval of conceptual information to suit the task or context. These aspects of semantic cognition are specifically impaired in patients with semantic dementia and semantic aphasia respectively. However, interactions between the structure of knowledge and control processes that are expected during semantic retrieval have not been fully characterised. In particular, domain-general executive resources may not have equal relevance for the capacity to promote weak yet relevant features (i.e., “controlled retrieval), and to ignore or suppress distracting information (i.e., “selection”). Here, using a feature selection task, we tested the contribution of featural relevance to semantic performance in healthy participants under conditions of divided attention. Healthy participants showed greater dual-task disruption as the relevance value of the distracter feature linearly increased, supporting the emerging view that semantic relevance is one of the organizing principles of the structure of semantic representation. Moreover, target relevance, word frequency and inter-correlational strength affected overall performance, but they did not show an interaction with dual-task conditions. These results suggest that domain-general control processes, disrupted by divided attention, are more relevant to the capacity to efficiently avoid distracting information during semantic decision-making than to the promotion of weak target features. The present study therefore provides novel information about the nature of the interaction between structured conceptual knowledge and control processes that support the retrieval of appropriate information, and relates these results to a new theoretical framework, termed controlled semantic cognition.

scholarly journals How do unfamiliar environments convey meaning to older people? Urban dimensions of placelessness and attachment

2012 ◽  
Vol 6 (2) ◽  
pp. 73-102 ◽  
Author(s):  
Judith Phillips ◽  
Nigel Walford ◽  
Ann Hockey
Keyword(s):  
Older People ◽  
Cognitive Decline ◽  
Sense Of Place ◽  
Place Attachment ◽  
Later Life ◽  
Conceptual Frameworks ◽  
Ageing In Place ◽  
The Relationship

The discussion within gerontology of the relationship between older people and their environment (place attachment and ageing in place in particular) has been based on an assumption of familiarity with place. Yet increasingly older people experience unfamiliar environments. This can be through increased travelling as tourists and visitors to other towns and cities, through redevelopment of town centres or through cognitive decline, where the familiar becomes unfamiliar. This article reviews the conceptual frameworks underpinning the concepts of place attachment and unfamiliarity and questions the relevance of such concepts for understanding urban lifestyles in later life. We demonstrate that even in an unfamiliar environment older people can develop a sense of place through the aesthetics and usability of the environment as well as through shared memories. Consequently this has relevance for how we plan our environments to make them age-friendly.

scholarly journals Divergent effects of healthy ageing on semantic knowledge and control: Evidence from novel comparisons with semantically-impaired patients

2017 ◽  
Author(s):  
Paul Hoffman
Keyword(s):  
Young People ◽  
Older People ◽  
Low Frequency ◽  
Poor Performance ◽  
Semantic Knowledge ◽  
Semantic Dementia ◽  
Control Processes ◽  
Dementia Patients ◽  
Abstract Words ◽  
And Control

AbstractEffective use of semantic knowledge requires a set of conceptual representations and control processes which ensure that currently-relevant aspects of this knowledge are retrieved and selected. It is well-established that levels of semantic knowledge increase across the lifespan. However, the effects of ageing on semantic control processes have not been assessed. I addressed this issue by comparing the performance profiles of young and older people on a verbal comprehension test. Two sets of variables were used to predict accuracy and RT in each group: (a) the psycholinguistic properties of words probed in each trial, (b) the performance on each trial by two groups of semantically-impaired neuropsychological patients. Young people demonstrated poor performance for low frequency and abstract words, suggesting that they had difficulty processing words with intrinsically weak semantic representations. Indeed, performance in this group was strongly predicted by the performance of patients with semantic dementia, who suffer from degradation of semantic knowledge. In contrast, older adults performed poorly on trials where the target semantic relationship was weak and distractor relationships strong – conditions which require high levels of controlled processing. Their performance was not predicted by the performance of semantic dementia patients, but was predicted by the performance of patients with semantic control deficits. These findings indicate that the effects of ageing on semantic cognition are more complex than has previously been assumed. While older people have larger stores of knowledge than young people, they appear to be less skilled at exercising control over the activation of this knowledge.

scholarly journals Elucidating the Nature of Deregulated Semantic Cognition in Semantic Aphasia: Evidence for the Roles of Prefrontal and Temporo-parietal Cortices

2010 ◽  
Vol 22 (7) ◽  
pp. 1597-1613 ◽  
Author(s):  
Krist A. Noonan ◽  
Elizabeth Jefferies ◽  
Faye Corbett ◽  
Matthew A. Lambon Ralph
Keyword(s):  
Executive Control ◽  
Conceptual Knowledge ◽  
Critical Role ◽  
Case Series ◽  
Semantic Knowledge ◽  
Semantic Dementia ◽  
Semantic Cognition ◽  
On Line ◽  
Parietal Cortices ◽  
Semantic Impairment

Semantic cognition—semantically driven verbal and nonverbal behavior—is composed of at least two interactive principal components: conceptual representations and executive control processes that regulate and shape activation within the semantic system. Previous studies indicate that semantic dementia follows from a progressive yet specific degradation of conceptual knowledge. In contrast, multimodal semantic impairment in aphasic patients (semantic aphasia [SA]) reflects damage to the control component of semantic cognition [Jefferies, E., & Lambon Ralph, M. A. Semantic impairment in stroke aphasia versus semantic dementia: A case-series comparison. Brain, 129, 2132–2147, 2006]. The purpose of the present study was to examine the nature of the semantic control deficits in SA in detail for the first time. Seven patients with SA were tested on four comprehension and naming tasks that directly manipulated the requirement for executive control in different ways. In line with many theories of cognitive control, the SA patients demonstrated three core features of impaired control: (i) they exhibited poor on-line manipulation and exploration of semantic knowledge; (ii) they exhibited poor inhibition of strongly associated distractors; and (iii) they exhibited reduced ability to focus on or augment less dominant aspects of semantic information, although the knowledge itself remained and could be successfully cued by external constraints provided by the examiner. Our findings are consistent with the notion that the anterior temporal lobes are crucial for conceptual knowledge whereas the left prefrontal and temporo-parietal cortices, damaged in patients with SA, play a critical role in regulating semantic activation in a task-appropriate fashion.

Introduction

2018 ◽  
pp. 1-18
Author(s):  
Anna Goulding
Keyword(s):  
Older People ◽  
Social Isolation ◽  
Later Life ◽  
Well Being ◽  
Cultural Practice ◽  
Cultural Engagement ◽  
Policy Initiatives ◽  
Response Policy ◽  
The Relationship

This introductory chapter provides an overview of the relationship between taking part in different forms of creative and cultural practice and the development of resilience in older people. There are significant challenges associated with old age and, as a response, policy initiatives have been developed which focus on reducing social isolation, improving well-being, and creating dementia-friendly communities. The chapters in this book provide crucial support for such initiatives by reporting findings that enhance understanding of how cultural engagement can develop both individual and community resilience. Indeed, through critically examining the meaning and value of creative engagement in later life, this book brings vital new understandings to the field of cultural gerontology.

scholarly journals The determinants of receiving social care in later life in England

2013 ◽  
Vol 35 (2) ◽  
pp. 321-345 ◽  
Author(s):  
A. VLACHANTONI ◽  
R. J. SHAW ◽  
M. EVANDROU ◽  
J. FALKINGHAM
Keyword(s):  
Older People ◽  
Activities Of Daily Living ◽  
Daily Living ◽  
Social Care ◽  
Later Life ◽  
Informal Support ◽  
Care Provision ◽  
The Future ◽  
The Relationship ◽  
Different Sources

ABSTRACTDemographic change and policy changes in social care provision can affect the type of social care support received by older people, whether through informal, formal state or formal paid-for sources. This paper analyses the English Longitudinal Study of Ageing data (wave 4) in order to examine the relationship between demographic and socio-economic characteristics, and the receipt of support from different sources by older people who report difficulty with daily activities. The research outlines three key results with implications for the future organisation of social care for older people. Firstly, the number of instrumental activities of daily living (IADLs) an older person reports having difficulty with, followed by the number of activities of daily living (ADLs) are the strongest determinants of receiving support from any source. Secondly, there are significant gender differences in the factors associated with receiving support from different sources; for example, physical health is a strong determinant of informal support receipt by men, while mental health status is a strong determinant of informal support receipt by women. Finally, the research shows that different kinds of impediments in everyday life are associated with receiving support from different sources. This ‘link’ between particular types of difficulties and support receipt from particular sources raises questions about the way social care provision can or should be organised in the future.

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