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Abstract: “Executive functions” is an umbrella term for functions such as planning, working memory, inhibition, mental flexibility, as well as the initiation and monitoring of action. The impairment of executive functions in various clinical groups is a topic of much debate, as are recent attempts to formulate the corresponding intervention and rehabilitation regimes of these dysfunctions. This article reviewed current theories of executive functions and their associated assessment instruments. In addition, it identified issues that are imperative for more accurate, sensitive, and specific assessment of various components of this construct. It is concluded that more research is needed to fractionate the executive system by assessing a wide range of functions and to verify their neuroanatomical correlates. Recently developed measurement models and technology may also facilitate a more ecologically and ethologically valid assessment for the specific needs of different individuals. [Copyright &y& Elsevier]

The expression of attentional blink (AB) in 24 schizophrenia inpatients was compared to 22 healthy subjects in a dual-target rapid serial visual presentation (RSVP) paradigm in which a sequence of discrete stimuli was presented in rapid succession. Correct identification of the first target led to poorer detection of the second one when they were interspersed by distractors. This second-target deficit constitutes the AB effect, which is most pronounced between 200 and 500 ms after the offset of the first target stimulus and steadily decays as the number of intervening distractors increases. Despite relatively poor performance in terms of target identification within RSVP streams, schizophrenia patients expressed an AB effect that was as clear as that seen in healthy subjects. Moreover, there was evidence for an enhanced AB effect in schizophrenia patients. This outcome contrasts with the robust finding that schizophrenia patients are attenuated in the expression of prepulse inhibition, another paradigm believed to assess attentional control. The present results add to the extensive literature on the nature and specification of attentional dysfunction implicated in schizophrenia. [ABSTRACT FROM PUBLISHER]