Landau–Kleffner syndrome

a rare childhood neurological disorder of unknown cause that is characterized by the sudden or gradual development of aphasia (inability to understand or express language) and an abnormal electroencephalogram (see electroencephalography). The syndrome usually occurs in children between the ages of 5 and 7 years who develop normally but then lose their language skills for no apparent reason. Many children with the disorder experience seizures, which generally disappear by adulthood. [first described in 1957 by William M. Landau and Frank R. Kleffner]

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Psychology term of the day

January 3rd 2025

noncontingent reinforcement

the process or circumstances in which a stimulus known to be effective as a reinforcer is presented independently of any particular behavior. Because contingencies may arise by accident (see accidental reinforcement), behavior-independent presentation of stimuli cannot guarantee that no contingency exists between a response and the stimuli. See reinforcement.