If Birds Have Sesamoid Bones, Do Blackbirds Have Sesamoid Bones? The Modification Effect With Known Compound Words.

Three experiments investigate how people infer properties of compound words from the unmodified head. Concepts license inference of properties true of the concept to instances or sub-types of that concept: Knowing that birds generally fly, one infers that a new type of bird flies. However, different names are also believed to reflect real underlying differences. Hence, a different name creates the expectation that a new bird differs from birds in general, and this might impact property inference. In these experiments, participants were told, Almost all (Some, Almost no) birds have sesamoid bones, and then asked, What percentage of blackbirds (birds) have sesamoid bones? The results indicate both inference and contrast effects. People infer properties as less common of the compound than the head when the property is true of the head, but they infer them as more common of the compound than the head when the property is not true of the head. In addition, inferences about properties true of the head are affected by the semantic similarity between the head and the compound, but properties not true of the head do not show any semantic similarity effect, but only a small, consistent effect of contrast. Finally, the presentation format (Open vs. Closed compounds) affects the pattern of effects only when the spacing suggests the existence of a permanent name.

Differential impairments of upper and lower limb movements influence action verb processing in Parkinson disease.

Theories of grounded cognition emphasize the role of the motor system in the processing of action concepts. The present study investigated whether persons with Parkinson disease (PD) who have greater upper versus greater lower limb motor impairments show different patterns of performance when processing action verbs. PD patients and controls made action decisions on upper-limb (reach), lower-limb (kick), and psych verbs (think). The primary result was an interaction between PD motor dominance (PD upper vs lower limb motor impairments) and verb type (upper- vs lower-limb verbs). PD patients with greater upper limb impairments took longer to respond to upper-limb than to lower-limb verbs, whereas those with greater lower limb impairments performed similarly on the two verb types. Our results add to recent studies and theories that highlight the complexity of verb impairments in PD, semantic task effects, effector-specific sensorimotor cortex engagement, and fine-grained semantic features and their possible interactions with effector-specific impairments.