Patterns of neurocognitive impairment in first-episode bipolar disorder and schizophrenia.

BACKGROUND:
Researching psychotic disorders in unison rather than as separate diagnostic groups is widely advocated, but the viability of such an approach requires careful consideration from a neurocognitive perspective.
AIMS:
To describe cognition in people with bipolar disorder and schizophrenia and to examine how known causes of variability in individual's performance contribute to any observed diagnostic differences.
METHOD:
Neurocognitive functioning in people with bipolar disorder (n = 32), schizophrenia (n = 46) and healthy controls (n = 67) was compared using analysis of covariance on data from the Northern Ireland First Episode Psychosis Study.
RESULTS:
The bipolar disorder and schizophrenia groups were most impaired on tests of memory, executive functioning and language. The bipolar group performed significantly better on tests of response inhibition, verbal fluency and callosal functioning. Between-group differences could be explained by the greater proclivity of individuals with schizophrenia to experience global cognitive impairment and negative symptoms.
CONCLUSIONS:
Particular impairments are common to people with psychosis and may prove useful as endophenotypic markers. Considering the degree of individuals' global cognitive impairment is critical when attempting to understand patterns of selective impairment both within and between these diagnostic groups.

Imitation and 'theory of mind' competencies in discrimination of autism from other neurodevelopmental disorders

Several studies have reported imitative deficits in autism spectrum disorder (ASD). However, it is still debated if imitative deficits are specific to ASD or shared with clinical groups with similar mental impairment and motor difficulties. We investigated whether imitative tasks can be used to discriminate ASD children from typically developing children (TD) and children with general developmental delay (GDD). We applied discriminant function analyses to the performance of these groups on three imitation tasks and tests of dexterity, motor planning, verbal skills, theory of mind (ToM). Analyses revealed two significant dimensions. The first represented impairment of dexterity and verbal ability, and discriminated TD from GDD children. Once these differences were accounted for, differences in ToM and the three imitation tasks accounted for a significant proportion of the remaining intergroup variance and discriminated the ASD group from other groups. Further analyses revealed that inclusion of imitative tasks increased the specificity and sensitivity of ASD classification and that imitative tasks considered alone were able to reliably discriminate ASD, TD and GDD. The results suggest that imitation and theory of mind impairment in autism may stem from a common domain of origin separate from general cognitive and motor skill.

Inductive reasoning and semantic cognition: More than just different names for the same thing?

We describe evidence that certain inductive phenomena are associated with IQ, that different inductive phenomena emerge at different ages, and that the effects of causal knowledge on induction are decreased under conditions of memory load. On the basis of this evidence we argue that there is more to inductive reasoning than semantic cognition.

Spatial Perception and Cognition in Multichannel Audio for Electroacoustic Music

Listeners experience electroacoustic music as full of significance and meaning, and they experience spatiality as one of the factors contributing to its meaningfulness. If we want to understand spatiality in electroacoustic music, we must understand how the listener’s mental processes give rise to the experience of meaning. In electroacoustic music as in everyday life, these mental processes unite the peripheral auditory system with human spatial cognition. In the discussion that follows we consider a range of the listener’s mental processes relating space and meaning from the perceptual attributes of spatial imagery to the spatial reference frames for places and navigation. When considering multichannel loudspeaker systems in particular, an important part of the discussion is focused on the distinctive and idiomatic ways in which this particular mode of sound production contributes to and situates meaning. These idiosyncrasies include the phenomenon of image dispersion, the important consequences of the precedence effect and the influence of source characteristics on spatial imagery. These are discussed in close relation to the practicalities of artistic practice and to the potential for artistic meaning experienced by the listener.