Trends in Cognitive Sciences
ReviewThe neurobiology of semantic memory
Section snippets
The centrality of semantic memory in human behavior
Human brains acquire and use concepts with such apparent ease that the neurobiology of this complex process seems almost to have been taken for granted. Although philosophers have puzzled for centuries over the nature of concepts [1], semantic memory (see Glossary) became a topic of formal study in cognitive science only relatively recently [2]. This history is remarkable, given that semantic memory is one of our most defining human traits, encompassing all the declarative knowledge we acquire
Central issues in semantic processing
A major issue in the study of semantic memory concerns the nature of concept representations. Efforts in the last century to develop artificial intelligence focused on knowledge representation in the form of abstract symbols [10]. This approach led to powerful new techniques for information representation and manipulation (e.g., semantic nets, feature lists, ontologies, schemata). Recent advances in this area used machine learning techniques together with massive verbal inputs to create a
Evidence for modality-specific simulation in comprehension
The idea that sensory and motor experiences form the basis of conceptual knowledge has a long history in philosophy, psychology, and neuroscience 1, 3, 12, 13. In recent years, this proposal has gained new steam under the rubric of ‘embodied’ or ‘situated’ cognition, supported by numerous neuroimaging and behavioral studies. Some of the imaging studies showing modality-specific activations during language processing are summarized in Figure 1. A number of these address action concepts and show
Evidence for high level convergence zones
In addition to modality-specific simulations, we propose that the brain uses abstract, supramodal representations during conceptual tasks. One compelling argument for this view is that the human brain possesses large areas of cortex that are situated between modal sensory-motor systems and thus appear to function as information ‘convergence zones’ [14]. These heteromodal areas include the inferior parietal cortex (angular and supramarginal gyri), large parts of the middle and inferior temporal
Embodied abstraction in conceptual representation
Figure 3 illustrates several prominent theories that differ in the proposed level of separation between conceptual and perceptual representations. Models based on disembodied, symbolic conceptual representations 9, 10 are often criticized on the grounds that such symbols are ultimately devoid of content [54]. From an empirical standpoint, the extensive evidence for involvement of modality-specific sensory, action, and emotion systems during language comprehension is also inconsistent with such
A neuroanatomical model of semantic processing
Figure 4 outlines a neuroanatomical model of semantic memory consistent with a broad range of available data. Modality-specific representations (yellow areas in Figure 4), located near corresponding sensory, motor, and emotion networks, develop as a result of experience with entities and events in the external and internal environment. These representations code recurring spatial and temporal configurations of lower-level modal representations. Although depicted as somewhat modular, we view
Social cognition, declarative memory retrieval, prospection, and the default mode
The network of brain regions we associate here with semantic processing has also been linked with more specific functions. Nearly all parts of the network have been implicated in aspects of social cognition, including theory-of-mind (processing of knowledge pertaining to mental states of other people), emotion processing, and knowledge of social concepts 36, 37, 63, 64, 65, 66, 67. Much of the network has been implicated in retrieval of episodic and particularly autobiographical memories 68, 69
Concluding remarks
This review proposes a large-scale brain model of semantic memory organization in the human brain based on synthesis of a large body of empirical imaging data with a modified embodiment theory of knowledge representation. In contrast to strong versions of embodiment theory, the data show that large areas of heteromodal cortex participate in semantic memory processes. The multimodal convergence of information toward these brain areas enables progressive abstraction of conceptual knowledge from
Acknowledgements
Supported by NIH grants R01 NS33576 and R01 DC010783. Thanks to Lisa Conant, Will Graves, Colin Humphries, Tim Rogers, and Mark Seidenberg for helpful discussions.
Glossary
- Embodied cognition
- in cognitive neuroscience, the general theory that perceptual and motor systems support conceptual knowledge, that is, that understanding or retrieving a concept involves some degree of sensory or motor simulation of the concept. A related term, situated cognition, refers to a more general perspective that emphasizes a central role of perception and action in cognition, rather than memory and memory retrieval.
- Heteromodal cortex
- cortex that receives highly processed, multimodal
References (109)
Neural systems behind word and concept retrieval
Cognition
(2004)Time-locked multiregional retroactivation: a systems-level proposal for the neural substrates of recall and recognition
Cognition
(1989)Recovering meaning: left prefrontal cortex guides semantic retrieval
Neuron
(2001)- et al.
A critical look at the embodied cognition hypothesis and a new proposal for grounding conceptual content
J. Physiol. (Paris)
(2008) Word processing in Parkinson's disease is impaired for action verbs but not for concrete nouns
Neuropsychologia
(2008)- et al.
Knowledge of object manipulation and object function: dissociations in apraxic and nonapraxic subjects
Brain Lang.
(2002) - et al.
The effects of motor neurone disease on language: further evidence
Brain Lang.
(2004) Listening to action-related sentences modulates the activity of the motor system: a combined TMS and behavioral study
Brain Res. Cogn. Brain Res.
(2005)Category-specific versus category-general semantic impairment induced by transcranial magnetic stimulation
Curr. Biol.
(2010)Different roles of lateral anterior temporal lobe and inferior parietal lobule in coding function and manipulation tool knowledge: evidence from an rTMS study
Neuropsychologia
(2011)
Emotional processing in anterior cingulate and medial prefrontal cortex
Trends Cogn. Sci.
Social cognition and the anterior temporal lobes
Neuroimage
Comparative mapping of higher visual areas in monkeys and humans
Trends Cogn. Sci.
Nonverbal semantic impairment in semantic dementia
Neuropsychologia
Colour knowledge in semantic dementia: it is not all black and white
Neuropsychologia
Meta-analysis of the functional neuroanatomy of single-word reading: method and validation
Neuroimage
On the status of object concepts in aphasia
Brain Lang.
Lesion analysis of the brain areas involved in language comprehension
Cognition
The symbol grounding problem
Phys. D
Other minds in the brain: a functional imaging study of ‘theory of mind’ in story comprehension
Cognition
People thinking about thinking people: the role of the temporo-parietal junction in ‘theory of mind’
Neuroimage
The functional neuroanatomy of autobiographical memory: A meta-analysis
Neuropsychologia
Memory retrieval and the parietal cortex: a review of evidence from a dual-process perspective
Neuropsychologia
Deconstructing episodic memory with construction
Trends Cogn. Sci.
Remembering the past and imagining the future: common and distinct neural substrates during event construction and elaboration
Neuropsychologia
Solving future problems: default network and executive activity associated with goal-directed mental simulations
Neuroimage
Associations and dissociations between default and self-reference networks in the human brain
Neuroimage
The parahippocampal gyrus: new observations regarding its cortical connections in the monkey
Trends Neurosci.
Dissociable controlled retrieval and generalized selection mechanisms in ventrolateral prefrontal cortex
Neuron
Functional specialization within the anterior medial prefrontal cortex: a functional magnetic resonance imaging study with human subjects
Neurosci. Lett.
Dissociable medial prefrontal contributions to judgments of similar and dissimilar others
Neuron
An essay concerning human understanding
Episodic and semantic memory
Components of the mental lexicon
Philos. Trans. R. Soc. Lond. B
Situated simulation in the human conceptual system
Lang. Cogn. Process.
Neuropsychological and neuroimaging perspectives on conceptual knowledge: an introduction
Cogn. Neuropsychol.
Where do you know what you know? The representation of semantic knowledge in the human brain
Nat. Rev. Neurosci.
Thought and language
The language of thought
Computation and cognition: toward a foundation for cognitive science
Building Watson: an overview of the DeepQA project
AI Mag.
Der aphasische Symptomenkomplex
On aphasia: a critical study
Role of left inferior prefrontal cortex in retrieval of semantic knowledge: a reevaluation
Proc. Natl. Acad. Sci. U.S.A.
Clinical, imaging and pathological correlates of a hereditary deficit in verb and action processing
Brain
Impaired action knowledge in amyotrophic lateral sclerosis
Neurology
All talk and no action: a transcranial magnetic stimulation study of motor cortex activation during action word production
J. Cogn. Neurosci.
Functional links between motor and language systems
Eur. J. Neurosci.
Processing abstract language modulates motor system activity
Q. J. Exp. Psychol.
Brain signatures of meaning access in action word recognition
J. Cogn. Neurosci.
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