SUMMARY This paper discusses neuropsychological and neurolinguistic aspects of specific language impairment (SLI), classified among the developmental speech disorders. SLI constitutes one of the more important manifestations of irregularities in the development process and is among the earliest ob- served in children. SLI results from the uneven development of linguistic processes – phonological, semantic and/or syntactic – and is caused by hereditary and environmental factors with a negative impact on the activity of the brain. One can speak of SLI in a particular child if the retardation in the development of speech and language reaches 12 months in comparison to the average level of linguistic competence in children of the same calendar age. We do not diagnose SLI if there are other reasons for the observed speech and language symptoms, such as serious sensory and cognitive deficits, permanent developmental impairments (e.g. autism), massive brain injury, or the lack of adequate social and emotional conditions for the devel- opment of communication skills. According to WHO categories, SLI manifests itself as an impairment of individual language functions resulting in disturbed communication with other people, which, in turn, leads to a handicap result- ing from social isolation, difficulties at school and consequent loss of the opportunity to adapt oneself to adult life in society. Even though the level of impairment in a given patient results from the pathology causing SLI, the handicap level depends on the patient's compensation ability, already avail- able or learned in the rehabilitation process, while the level of limitation depends on the patient's adaptation to the existing situation. The problems of SPECIFIC LANGUAGE IMPAIRMENT : NEUROPSYCHOLOGICAL AND NEUROLINGUISTIC ASPECTS Maria P¹chalska 1 , Gra¿yna Jastrzêbowska 2 , Ma³gorzata Lipowska 1 , Anna Pufal 3 1 Institute of Psychology, University of Gdañsk, Gdañsk, Poland 2 University of Opole, Opole, Poland 3 Center for Cognition and Communication, New York, NY Key words: developmental neuropsychology, intellectual impairment, linguistic competence 131 ORIGINAL ARTICLE ACT ACT A Vol. 5, No. 3, 2007, 131-154 NEUROPSYCHOLOGICA NEUROPSYCHOLOGICA