A COMMON STORAGE MECHANISM IN SHORT- TERM, WORKING AND LONG-TERM MEMORY? SOME EVIDENCE FROM CONTROL AND SCHIZOPHRENIA SAMPLES.

摘要: [Abstract]: Background: Baddeley and Hitch’s (1974) multi-component model of working memory (WM) has provided the basis for exploration into nature remembering manipulating information over a short period time. This argues that passive short-term storage system is not involved in more dynamic tasks formed much research on clinical populations known to have deficits WM. However, other models argue that rely common storage facilities. The aim this thesis was explore whether there justification continued separation WM fractionated components. Schizophrenia (SZ) associated with wide range cognitive deficits, including problems. There also some evidence suggest psychotic symptoms exist continuum similar those found SZ been reported people endorsing “psychotic-like” without formal diagnosis schizophrenia. It hypothesized that pattern errors made by group would help delineate deficit shown tasks. Methods: General Methods In order structure performance groups hypothesized be impaired tasks, span non-span were administered. Forty-two (42) control subjects recruited study. Based their scores Schizotypal Personality Questionnaire (SPQ - Raine, 1991), divided low scoring (NCL = 27 ) high (NCH 15) groups. Thirty (30) DSM-IV schizophrenia recruited. Experiment 1 Experiment one investigated these simple, complex delayed tasks. A simple four-word recall task, interference used examine accuracy, error types any relationship symptomatology. Experiment 2 Experiment two set out investigate contributions performance. All administered measures articulation speed, lexical access ability, STM, LTM tasks. Experiment 3 This experiment cued-recall paradigm proactive effects phonological semantic representations brief periods. task consisted trials where subject studied series or blocks four words. Results: Experiment 1 The results replicated previous findings (Tehan, Hendry & Kocinski, 2001) patterns across three with performance decrements increasing difficulty. showed significant even task. Patterns once overall levels taken account. movement (order) than disorganised symptoms. association between symptoms and loss items from end list suggestive maintenance item information. schizotypy performed below controls, but only few differences significant. Experiment 2 For both composites. For group, all contributed form single factor. separate composites needed. Using regression analyses (Tehan Lalor, 2000; Tehan, Fogarty Ryan, 2004) lesser degree, rehearsal speed contributing performance. Rehearsal important predictor familiar materials (such as letters digits) group. reverse true word span, making impact having little impact. tasks, neither rate nor Once again poorer symptoms. Experiment 3 The revealed block trials, had difficulty accurately recalling target a category cue, absence distractor activity. omissions significantly intrusion Intrusion the Positive Negative Symptom Scale (PANSS). Despite performance, did block-1 intrusions suggesting phonemic same. Conclusions: This presented which somewhat supportive approach calls question need fractionate WM into components. often subjects, population know deficits. Errors examined compared controls: a group measure psychometric scores. Implications regarding purported source are discussed.