Humans, being highly social creatures, rely heavily on the ability to perceive what others are doing and to infer from gestures and expressions what others may be intending to do. These perceptual skills are easily mastered by most, but not all, people, in large part because human action readily communicates intentions and feelings. In recent years, remarkable advances have been made in our understanding of the visual, motoric, and affective influences on perception of human action, as well as in the (...) elucidation of the neural concomitants of perception of human action. This article reviews those advances and, where possible, draws links among those findings.Acronyms and DefinitionsApparent motion: perception of smooth motion from brief, successive exposures of static imagesChameleon effect: tendency for people to mimic the actions of others without even knowing itCommon coding principle: theory that perceiving and acting share common mental representationsDynamic noise: an array of randomly positioned dots that can camouflage perception of PL animations when the noise dots are sufficiently denseEvent-related potential : electrical brain activity registered from the scalpExtrastriate body area : brain region activated when a person views a human body or body partsFunctional magnetic resonance imaging : widely used technique that reveals brain activation patterns based on hemodynamic responses to neural activityInversion effect: difficulty of perceiving PL animations when they are shown upside downKinematics: analysis of the motions of objects without regard to the forces producing themMirror neurons: brain cells responsive when an animal engages in an activity or when it watches another animal engaged in that activityPoint-light animations: biological activity portrayed by small light tokens placed on the major body parts of an actorPositron emission tomography : brain imaging technique that uses radioactively labeled tracers to allow visualization of active brain areasSpatiotemporal jitter: means of degrading perception of PL animations, where the relative timing and positions of the moving dots are perturbedSuperior temporal sulcus : region of the cortex the posterior portion of which contains neurons selectively responsive to human activityTemplate-matching model: theory that perception of biological motion results from concatenation of static views of the bodyTranscranial magnetic stimulation : technique producing a brief disruption of neural processing. (shrink)

The study argues that linguistic/communication dysfunctions present in disorganized schizophrenia may stem, at least in part, from an impaired theory of mind. Using pragmatics and systemic linguistic theory, the study examined speech samples of two disorganized schizophrenic patients and attempted to determine if their communicative failures are because they lack theory of mind in the sense that they do not take into account the interlocutor's mind, i.e., the interlocutor's intentions, dispositions, and knowledge; or because they have a hyper-theory of mind (...) through which they over-attribute mental states to their interlocutor, i.e., assume that their interlocutor has access to their intentions, dispositions, and knowledge. The study indicates that disorganized schizophrenics are unlikely to be characterized as lacking a theory of mind; rather they seem to have a hyper-theory of mind, to which the psychopathological symptoms of hallucinations, delusions of reference and incoherent speech can be attributed. (shrink)

Recurrent microdeletions and microduplications of a 600-kb genomic region of chromosome 16p11.2 have been implicated in childhood-onset developmental disorders. We report the association of 16p11.2 microduplications with schizophrenia in two large cohorts. The microduplication was detected in 12/1,906 cases and 1/3,971 controls from the initial cohort, and in 9/2,645 cases and 1/2,420 controls of the replication cohort. The 16p11.2 microduplication was associated with a 14.5-fold increased risk of schizophrenia ) in the combined sample. A meta-analysis of datasets for multiple psychiatric (...) disorders showed a significant association of the microduplication with schizophrenia, bipolar disorder and autism. In contrast, the reciprocal microdeletion was associated only with autism and developmental disorders. Head circumference was larger in patients with the microdeletion than in patients with the microduplication. © 2009 Nature America, Inc. All rights reserved. (shrink)