Biological psychology
-
Biological psychology · Oct 2008
Relationship between trait anxiety, prefrontal cortex, and attention bias to angry faces in children and adolescents.
Using event-related functional magnetic resonance imaging (fMRI) with a visual-probe task that assesses attention to threat, we investigated the cognitive and neurophysiological correlates of trait anxiety in youth. During fMRI acquisition, 16 healthy children and adolescents viewed angry-neutral face pairs and responded to a probe that was on the same (angry-congruent) or opposite (angry-incongruent) side as the angry face. ⋯ Neurophysiologically, trait anxiety was positively associated with right dorsolateral prefrontal cortex (PFC) activation on a contrast of trials that reflect the attention bias for angry faces (i.e. angry-incongruent versus angry-congruent trials). Trait anxiety was also positively associated with right ventrolateral PFC activation on trials with face stimuli (vesus baseline), irrespective of their emotional content.
-
Biological psychology · Oct 2008
A study on the neural mechanism of inhibition of return by the event-related potential in the Go/NoGo task.
Inhibition of return (IOR) is a slowed response to a stimulus at recently cued locations when stimulus-onset asynchronies (SOAs) are longer than 250 ms. Using an uninformative peripheral cued Go/NoGo (commit/withdrawal response) task experiment, this study aimed to characterize the neural mechanism of IOR by studying not only the early event-related potentials (ERPs), P1 and N1, but also the late ERPs, Go/NoGo-N2 and P3. Scalp topographies and LORETA showed that the changes in P1 and N1, the cueing effects, were distributed mainly over the dorsal occipito-parietal areas, such as the bilateral middle occipital gyrus and the occipital portion of the cuneus. ⋯ The NoGo-N2 was smaller and earlier in valid trials than in invalid trials, suggesting that the late component related to IOR was modulated by response preparation inhibition. The NoGo-P3 was larger and later in valid trials than in invalid trials, perhaps indicating that the control system (FEF) was free from an inhibitory marker in the cued locations. These data support a mechanism of IOR consisting of both sensory inhibition and response preparation inhibition.