Changing perspectives on Landau-Kleffner syndrome.

Landau-Kleffner syndrome (LKS) is a childhood disorder characterized by an acquired aphasia that emerges in association with epileptiform electroencephalographic abnormalities. The language loss is often characterized by a severe disturbance of auditory language comprehension (verbal auditory agnosia) combined with a substantial disruption of expressive language. Comorbid behavioral disturbances commonly involve hyperactivity and attentional problems but sometimes encompass a more pervasive pattern of difficulties resembling an autism spectrum disorder.

The ontogenesis of language impairment in autism: a neuropsychological perspective.

Autistic Disorder (AD) is a phenotypically heterogeneous condition characterized by impairments in social interaction, communication, and the presence of repetitive behavior and restricted interests. It is a model syndrome to investigate neural interaction and integration at the nexus of language and social cognition. This paper considers the problems of language acquisition in AD from an evolutionary and ontogenetic context.

Regression in autistic spectrum disorders.

A significant proportion of children diagnosed with Autistic Spectrum Disorder experience a developmental regression characterized by a loss of previously-acquired skills. This may involve a loss of speech or social responsitivity, but often entails both. This paper critically reviews the phenomena of regression in autistic spectrum disorders, highlighting the characteristics of regression, age of onset, temporal course, and long-term outcome.

Speech perceived through a damaged temporal window: lessons from word deafness and aphasia.

Word deafness is an intriguing neurological syndrome characterized by severe difficulties in the ability to understand or reproduce spoken language with otherwise intact speech production and nonauditory language comprehension. The disorder is of significant theoretical importance because it putatively supports the modularity of speech recognition from more central language computational networks. However, the specificity and functional locus of the processing disturbances resulting in word deafness remains unclear.

Cognitive and motor development during childhood in boys with Klinefelter syndrome.

The goal of this study was to expand the description of the cognitive development phenotype in boys with Klinefelter syndrome (47,XXY). We tested neuropsychological measures of memory, attention, visual-spatial abilities, visual-motor skills, and language. We examined the influence of age, handedness, genetic aspects (parental origin of the extra X chromosome, CAG(n) repeat length, and pattern of X inactivation), and previous testosterone treatment on cognition.