scholarly journals Enhancing vs. inhibiting semantic performance with transcranial magnetic stimulation over the anterior temporal lobe: Frequency- and task-specific effects

NeuroImage ◽  
2021 ◽  
Vol 234 ◽  
pp. 117959
Author(s):  
JeYoung Jung ◽  
Matthew A. Lambon Ralph
Keyword(s):  
Transcranial Magnetic Stimulation ◽  
Temporal Lobe ◽  
Magnetic Stimulation ◽  
Anterior Temporal Lobe ◽  
Specific Effects ◽  
And Task

scholarly journals Enhancing vs. inhibiting semantic performance with repetitive transcranial magnetic stimulation over the anterior temporal lobe: frequency- and task- specific effects

2019 ◽  
Author(s):  
JeYoung Jung ◽  
Matthew A. Lambon Ralph
Keyword(s):  
Transcranial Magnetic Stimulation ◽  
Temporal Lobe ◽  
Magnetic Stimulation ◽  
Semantic Processing ◽  
Repetitive Transcranial Magnetic Stimulation ◽  
Semantic Representation ◽  
Healthy Individuals ◽  
Anterior Temporal Lobe ◽  
Specific Effects ◽  
Virtual Lesion

AbstractAccumulating, converging evidence indicates that the anterior temporal lobe (ATL) appears to be the transmodal hub for semantic representation. A series of repetitive transcranial magnetic stimulation (rTMS) investigations utilizing the ‘virtual lesion’ approach have established the brain-behavioural relationship between the ATL and semantic processing by demonstrating that inhibitory rTMS over the ATL induced impairments in semantic performance in healthy individuals. However, a growing body of rTMS studies suggest that rTMS might also be a tool for cognitive enhancement and rehabilitation, though there has been no previous exploration in semantic cognition. Here, we explored a potential role of rTMS in enhancing and inhibiting semantic performance with contrastive rTMS protocols (1Hz vs. 20Hz) by controlling practice effects. Our results demonstrated that it is possible to modulate semantic performance positively or negatively depending on the ATL stimulation frequency: 20Hz rTMS was optimal for facilitating cortical processing (faster RT in a semantic task) contrasting with diminished semantic performance after 1Hz rTMS. In addition to cementing the importance of the ATL to semantic representation, our findings suggest that 20Hz rTMS leads to semantic enhancement in healthy individuals and potentially could be used for patients with semantic impairments as a therapeutic tool.

Neurochemical profiles of the anterior temporal lobe predict response of repetitive transcranial magnetic stimulation on semantic processing

2021 ◽  
Author(s):  
JeYoung Jung ◽  
Stephen Williams ◽  
Faezeh Sanae Nezhad ◽  
Matthew Lambon Ralph
Keyword(s):  
Transcranial Magnetic Stimulation ◽  
Temporal Lobe ◽  
Magnetic Stimulation ◽  
Semantic Processing ◽  
Cortical Excitability ◽  
Repetitive Transcranial Magnetic Stimulation ◽  
Semantic Representation ◽  
Cortical Region ◽  
Anterior Temporal Lobe ◽  
Neurochemical Profiles

Abstract The effect of repetitive transcranial magnetic stimulation can vary considerably across individuals, but the reasons for this still remain unclear. Here, we investigated whether the response to continuous theta-burst stimulation (cTBS) – an effective protocol for decreasing cortical excitability – related to individual differences in glutamate and GABA neurotransmission. We applied cTBS over the anterior temporal lobe (ATL), a hub for semantic representation, to explore the relationship between the baseline neurochemical profiles in this region and the response to this stimulation. Our experiments revealed that non-responders (subjects who did not show an inhibitory effect of cTBS on subsequent semantic performance) had higher excitatory-inhibitory balance (glutamate + glutamine/GABA ratio) in the ATL, which led to up-regulated task-induced regional activity as well as increased ATL-connectivity with other semantic regions compared to responders. These results disclose that the baseline neurochemical state of a cortical region can be a significant factor in predicting responses to cTBS.

Cortical Excitability by Transcranial Magnetic Stimulation as Biomarkers for Seizure Controllability in Temporal Lobe Epilepsy

2019 ◽  
Vol 23 (3) ◽  
pp. 399-406
Author(s):  
Han‐Wei Huang ◽  
Jing‐Jane Tsai ◽  
Pei‐Fang Su ◽  
Yu‐Lin Mau ◽  
Yi‐Jen Wu ◽  
...  
Keyword(s):  
Transcranial Magnetic Stimulation ◽  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Magnetic Stimulation ◽  
Cortical Excitability

Specific and non-specific effects of transcranial magnetic stimulation on simple and go/no-go reaction time

1999 ◽  
Vol 127 (4) ◽  
pp. 402-408 ◽  
Author(s):  
L. Sawaki ◽  
Tsunetaka Okita ◽  
Makoto Fujiwara ◽  
Kosaku Mizuno
Keyword(s):  
Reaction Time ◽  
Transcranial Magnetic Stimulation ◽  
Magnetic Stimulation ◽  
Specific Effects

scholarly journals Transcranial magnetic stimulation with a half-sine wave pulse elicits direction-specific effects in human motor cortex

2012 ◽  
Vol 13 (1) ◽  
pp. 139 ◽  
Author(s):  
Nikolai H Jung ◽  
Igor Delvendahl ◽  
Astrid Pechmann ◽  
Bernhard Gleich ◽  
Norbert Gattinger ◽  
...  
Keyword(s):  
Transcranial Magnetic Stimulation ◽  
Motor Cortex ◽  
Magnetic Stimulation ◽  
Sine Wave ◽  
Human Motor Cortex ◽  
Wave Pulse ◽  
Specific Effects ◽  
Human Motor

scholarly journals Dynamic semantic cognition: Characterising coherent and controlled conceptual retrieval through time using magnetoencephalography and chronometric transcranial magnetic stimulation

2017 ◽  
Author(s):  
Catarina Teige ◽  
Giovanna Mollo ◽  
Rebecca Millman ◽  
Nicola Savill ◽  
Jonathan Smallwood ◽  
...  
Keyword(s):  
Transcranial Magnetic Stimulation ◽  
Temporal Lobe ◽  
Magnetic Stimulation ◽  
Temporal Dynamics ◽  
Temporal Cortex ◽  
Brain Regions ◽  
Middle Temporal Gyrus ◽  
Semantic Retrieval ◽  
Current Task ◽  
Stimulation Of

AbstractDistinct neural processes are thought to support the retrieval of semantic information that is (i) coherent with strongly-encoded aspects of knowledge, and (ii) non-dominant yet relevant for the current task or context. While the brain regions that support coherent and controlled patterns of semantic retrieval are relatively well-characterised, the temporal dynamics of these processes are not well-understood. This study used magnetoencephalography (MEG) and dual-pulse chronometric transcranial magnetic stimulation (cTMS) in two separate experiments to examine temporal dynamics within the temporal lobe during the retrieval of strong and weak associations. MEG results revealed a dissociation within left temporal cortex: anterior temporal lobe (ATL) showed greater oscillatory response for strong than weak associations, while posterior middle temporal gyrus (pMTG) showed the reverse pattern. In the cTMS experiment, stimulation of ATL at ~150ms disrupted the efficient retrieval of strong associations, indicating a necessary role for ATL in coherent conceptual activations. Stimulation of pMTG at the onset of the second word disrupted the retrieval of weak associations, suggesting this site may maintain information about semantic context from the first word, allowing engagement of semantic control. Together these studies provide converging evidence for a functional dissociation within the temporal lobe, across both tasks and time.

Sign in / Sign up

Export Citation Format

Share Document