The Roles of Left Versus Right Anterior Temporal Lobes in Conceptual Knowledge: An ALE Meta-analysis of 97 Functional Neuroimaging Studies

The role of the anterior temporal lobes (ATLs) in semantic cognition is not clear from the current literature. Semantic dementia patients show a progressive and a specific semantic impairment, following bilateral atrophy of the ATLs. Neuroimaging studies of healthy participants, however, do not consistently show ATL activation during semantic tasks. Consequently, several influential theories of semantic memory do not ascribe a central role to the ATLs. We conducted a meta-analysis of 164 functional neuroimaging studies of semantic processing to investigate factors that might contribute to the inconsistency in previous results. Four factors influenced the likelihood of finding ATL activation: (1) the use of PET versus fMRI, reflecting the fact that fMRI but not PET is sensitive to distortion artifacts caused by large variations in magnetic susceptibility in the area of the ATL; (2) a field of view (FOV) of more than 15 cm, thereby ensuring whole-brain coverage; (3) the use of a high baseline task to prevent subtraction of otherwise uncontrolled semantic activation; (4) the inclusion of the ATL as an ROI. The type of stimuli or task did not influence the likelihood of ATL activation, consistent with the view that this region underpins an amodal semantic system. Spoken words, written words, and picture stimuli produced overlapping ATL peaks. On average, these were more inferior for picture-based tasks. We suggest that the specific pattern of ATL activation may be influenced by stimulus type due to variations across this region in the degree of connectivity with modality-specific areas in posterior temporal cortex.

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The anterior temporal lobes are critically involved in acquiring new conceptual knowledge: Evidence for impaired feature integration in semantic dementia

Cortex ◽

10.1016/j.cortex.2013.10.006 ◽

2014 ◽

Vol 50 ◽

pp. 19-31 ◽

Cited By ~ 21

Author(s):

Paul Hoffman ◽

Gemma A.L. Evans ◽

Matthew A. Lambon Ralph

Keyword(s):

Conceptual Knowledge ◽

Semantic Dementia ◽

Feature Integration ◽

Temporal Lobes ◽

Anterior Temporal Lobes

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A tale of two hemispheres: Contrasting socioemotional dysfunction in right- versus left-lateralised semantic dementia

Dementia & Neuropsychologia ◽

10.1590/s1980-57642013dn70100014 ◽

2013 ◽

Vol 7 (1) ◽

pp. 88-95 ◽

Cited By ~ 27

Author(s):

Muireann Irish ◽

Fiona Kumfor ◽

John R. Hodges ◽

Olivier Piguet

Keyword(s):

Conceptual Knowledge ◽

Semantic Processing ◽

Empathic Concern ◽

Semantic Dementia ◽

Facial Emotions ◽

Temporal Lobes ◽

Progressive Degeneration ◽

Left And Right ◽

Anterior Temporal Lobes ◽

The Right

ABSTRACT Objective: Semantic dementia, a subtype of frontotemporal lobar degeneration, is characterised by cross-modal loss of conceptual knowledge attributable to progressive degeneration of the left anterior temporal lobe. Much less is known regarding the clinical presentation of SD patients with predominantly right-lateralised atrophy. Recent reports emphasise marked socioemotional and behavioural disturbances in such cases. Given the importance of the right anterior temporal lobes in social cognition, we hypothesised that socioemotional functioning would be disproportionately affected in right versus left-lateralised SD cases. Methods: We assessed well-characterised cases of predominantly right (n=10) and left (n=12) SD and 20 matched healthy controls on tests of emotion processing and interpersonal functioning. Results: Right SD cases showed disproportionate difficulties in the recognition of positive and negative facial emotions, specifically happiness and anger, compared with left SD cases. Deficits in anger recognition persisted in right SD despite covarying for facial and semantic processing. On a contextually rich task of emotion recognition using multimodal videos, no subgroup differences were evident. Finally, empathic concern was rated as significantly lower by caregivers of right versus left SD cases. Overall, the extent of socioemotional disturbance was associated with the degree of behavioural changes in SD. Conclusion: Our results reveal considerable overlap in the extent to which socioemotional processes are disrupted in left and right-lateralised cases of SD. Notably, however, right SD cases show disproportionate deficits for recognition of facial emotions and the capacity for empathic concern, supporting a specialised role for the right anterior temporal lobes in mediating these cognitive functions.

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Differential Activity for Animals and Manipulable Objects in the Anterior Temporal Lobes

Journal of Cognitive Neuroscience ◽

10.1162/jocn.2010.21567 ◽

2011 ◽

Vol 23 (8) ◽

pp. 2059-2067 ◽

Cited By ~ 24

Author(s):

Stefano Anzellotti ◽

Bradford Z. Mahon ◽

Jens Schwarzbach ◽

Alfonso Caramazza

Keyword(s):

Conceptual Knowledge ◽

Bold Signal ◽

Object Processing ◽

Susceptibility Artifacts ◽

Temporal Lobes ◽

Semantic Categories ◽

Temporal Pole ◽

Anterior Temporal Lobes ◽

The Right ◽

Neuropsychological Findings

Neuropsychological evidence has highlighted the role of the anterior temporal lobes in the processing of conceptual knowledge. That putative role is only beginning to be investigated with fMRI as methodological advances are able to compensate for well-known susceptibility artifacts that affect the quality of the BOLD signal. In this article, we described differential BOLD activation for pictures of animals and manipulable objects in the anterior temporal lobes, consistent with previous neuropsychological findings. Furthermore, we found that the pattern of BOLD signal in the anterior temporal lobes is qualitatively different from that in the fusiform gyri. The latter regions are activated to different extents but always above baseline by images of the preferred and of the nonpreferred categories, whereas the anterior temporal lobes tend to be activated by images of the preferred category and deactivated (BOLD below baseline) by images of the nonpreferred category. In our experimental design, we also manipulated the decision that participants made over stimuli from the different semantic categories. We found that in the right temporal pole, the BOLD signal shows some evidence of being modulated by the task that participants were asked to perform, whereas BOLD activity in more posterior regions (e.g., the fusiform gyri) is not modulated by the task. These results reconcile the fMRI literature with the neuropsychological findings of deficits for animals after damage to the right temporal pole and suggest that anterior and posterior regions within the temporal lobes involved in object processing perform qualitatively different computations.

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A case study investigating the role of the anterior temporal lobes in general semantics and semantics specific to persons, emotions and social conceptual knowledge

Journal of Neuropsychology ◽

10.1111/jnp.12236 ◽

2020 ◽

Author(s):

Jennifer A. Foley ◽

Harpreet Hyare ◽

Jeremy H. Rees ◽

Diana Caine

Keyword(s):

Conceptual Knowledge ◽

Temporal Lobes ◽

General Semantics ◽

Anterior Temporal Lobes

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The anterior temporal lobes and the functional architecture of semantic memory

Journal of the International Neuropsychological Society ◽

10.1017/s1355617709990348 ◽

2009 ◽

Vol 15 (5) ◽

pp. 645-649 ◽

Cited By ~ 116

Author(s):

W. KYLE SIMMONS ◽

ALEX MARTIN

Keyword(s):

Semantic Memory ◽

Conceptual Knowledge ◽

Future Research ◽

Functional Architecture ◽

Temporal Lobes ◽

Anterior Temporal Lobes ◽

General Semantic

AbstractRecently, three accounts have emerged on the role of the anterior temporal lobes (ATLs) in semantic memory. One account claims that the ATLs are domain-general semantic hubs, another claims that they underlie knowledge of unique entities specifically, and yet another account claims that they support social conceptual knowledge generally. Here, we review neuropsychological and neuroimaging studies that bear on these three accounts and offer suggestions for future research to elucidate the roles of the ATLs in semantic memory. (JINS, 2009, 15, 645–649.)

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