“…Neuropsychological data continues to help elucidate this issue by providing behavioral measures that can be linked to regional brain function. Evidence for impaired learning and memory (e.g., Calev et al, 1983;Saykin et al, 1991;Goldberg et al, 1993), attention (e.g., Nuechterlein and Dawson, 1984;Harvey et al, 1990;Nestor et al, 1992), and executive functions (e.g., Goldberg et al, 1987;Morrison-Stewart et al, 1992) has supported a model of fronto-temporal dysfunction in schizophrenia. The presence of these deficits at first presentation (e.g., Bilder et al, 1992;Saykin et al, 1994), combined with the lack of correlation with measures of chronicity (e.g., Goldberg et al, 1993;Nopoulos et al, 1994) are consistent with the neurodevelopmental hypothesis that stresses the relative stability of cognitive functions after the onset of schizophrenia (e.g., Weinberger, 1987;Wyatt, 1996).…”