Brain stimulation revealed new knowledge on semantic memory

Semantic control system regulates retrieval of knowledge according to current needs. We studied the brain mechanisms of this system using non-invasive transcranial direct current stimulation (tDCS) and found that stimulation of the left lateral prefrontal cortex improved inhibition of pre-potent semantic associations but not retrieval of habitual associations or switching between retrieval rules. Our findings show that the semantic control is not unitary, but involves distinct cognitive and neural processes. The left lateral prefrontal cortex seems to implement an inhibitory semantic control process, which adaptively constrains the access to memory contents or suppresses contents, which have been already retrieved, but are not appropriate or useful in given moment.

The study was conducted by our colleagues Martin Marko a Igor Riečanský.

The article can be retrieved at https://doi.org/10.1016/j.cortex.2020.11.001