Practice-related Changes in Human Brain Functional Anatomy during Nonmotor Learning

Abstract

Practice of a novel task leads to improved performance. The brain mechanisms associated with practice-induced improvement in performance are largely unknown. To address this question we have examined the functional anatomy of the human brain with positron emission tomography (PET) during the naive and practiced performance of a simple verbal response selection task (saying an appropriate verb for a visually presented noun). As a control state, subjects were asked to repeat the visually presented nouns. Areas of the brain most active during naive performance (anterior cingulate, left prefrontal and left posterior temporal cortices, and the right cerebellar hemisphere), compared to repeating the visually presented nouns, were all significantly less active during practiced performance. These changes were accompanied by changes in the opposite direction in sylvian-insular cortex bilaterally and left medial extrastriate cortex. In effect, brief practice made the cortical circuitry used for verbal response selection indistinguishable from simple word repetition. Introduction of a novel list of words reversed the learning-related effects. These results indicate that two distinct circuits can be used for verbal response selection and normal subjects can change the brain circuits used during task performance following less than 15 min of practice. One critical factor in determining the circuitry used appears to be the degree to which a task is learned or automatic.

Cytology and functionally correlated circuits of human posterior cingulate areas

“…Another study that may at first appear to be at odds with our conclusion is a study of self-referential trait adjectives which showed an increase in ACC and a decrease in dPCC (Kelley et al, 2002). This latter study, however, more likely engaged word selection processes much as the verb generation task of Raichle et al (1994) rather than an internal self-evaluative state. The brain pattern of activation and inactivation sites supports its similarity to word generation tasks (Raichle, 2000).…”

The role of age of acquisition and language usage in early, high‐proficient bilinguals: An fMRI study during verbal fluency

“…Representations in a particular brain area are said to contract (or expand) so that they can occupy a smaller (or larger) plot of neural "real estate," an effect termed "representational plasticity" (Donoghue, 1995). Practice-related changes in a wordgeneration task have been observed in a study where the prefrontal brain areas were less active in the wellpracticed automatic condition (Raichle et al, 1994). Later, Petersen et al (1998) further investigated the effects of practice on a verbal task using PET.…”

Executive Attention and Metacognitive Regulation

“…In go/no-go tasks, the motor response needs to be inhibited whenever a no-go trial occurs. Imaging studies reveal activation of the anterior cingulate in both of these tasks (Casey, Trainor, Orendi et al, 1997;Raichle et al, 1994).…”