Patients with multimodal semantic impairment following
stroke (referred to here as ‘semantic aphasia’, SA) are highly
sensitive to the cognitive control demands of the task being
performed and poor at inhibiting strongly associated
distracters and focusing on less dominant aspects of meaning.
Here, using feature selection tasks, we tested the role played
by a semantic measure of featural salience on the control
processes in healthy participants (Experiment 1) and SA
patients (Experiment 2). Healthy participants showed a worse
performance when the distracter feature was highly salient
and the target feature was less salient for the concept, i.e.,
when there was an interference with voluntary selection of the
target feature (Experiment 1). Consistent with these results,
the SA patients showed a poorer performance than older
controls when the target feature was weakly related to the
concept (Experiment 2). In line with the feature-based models
of the semantic memory, we discuss these preliminary results
in term of greater demands of controlled semantic retrieval
when the features are weakly related to the concept in the
semantic network.
