Dougherty D M, Steinberg J L, Wassef A A, Medearis D, Cherek D R, Moeller F G
Harris County Psychiatric Center, Department of Psychiatry and Behavioral Sciences, University of Texas at Houston Health Science Center, 77030, USA.
Psychiatry Res. 1998 Jul 13;79(3):255-65. doi: 10.1016/s0165-1781(98)00040-7.
In an exploratory study, 10 schizophrenic patients and 10 normal control subjects performed immediate and delayed memory tasks, which were variants of previously developed continuous performance tests. Both tasks required participants to identify five-digit numbers which were repeated. Numbers were presented in series for 500 ms each and separated by a 500-ms time-out period. In the immediate memory task, subjects were to respond if a number was identical to the one that had immediately preceded it. The delayed memory task differed from the first task in that a longer delay (3.5 s) between stimuli was introduced, and during this delay distracter stimuli appeared. While normal control subjects performed accurately on both tasks (exceeding 80% correct detections), schizophrenic patients performed poorly, performing worse on the delayed memory task than on the immediate memory task. Rates of commission errors (responses made to similar, but not identical numbers) were nearly equal between groups on the immediate memory task, but on the delayed memory task normal control subjects made relatively more commission errors while schizophrenic patients made fewer commission errors. No differences in response latencies were observed between subject groups or tasks. This paradigm may prove useful in discriminating subtle differences in immediate and delayed memory capability among psychiatric populations and normal control subjects.
在一项探索性研究中，10名精神分裂症患者和10名正常对照受试者进行了即时和延迟记忆任务，这些任务是先前开发的连续性能测试的变体。两项任务都要求参与者识别重复出现的五位数字。数字以系列形式每次呈现500毫秒，中间间隔500毫秒的超时时间。在即时记忆任务中，如果一个数字与紧接在其前面的数字相同，受试者就要做出反应。延迟记忆任务与第一个任务的不同之处在于，刺激之间引入了更长的延迟（3.5秒），并且在这段延迟期间会出现干扰刺激。虽然正常对照受试者在两项任务上都表现准确（正确检测率超过80%），但精神分裂症患者表现较差，在延迟记忆任务上比在即时记忆任务上表现更差。在即时记忆任务中，两组的错误肯定率（对相似但不相同数字做出的反应）几乎相等，但在延迟记忆任务中，正常对照受试者的错误肯定率相对较高，而精神分裂症患者的错误肯定率较低。在受试者组或任务之间未观察到反应潜伏期的差异。这种范式可能被证明有助于区分精神疾病患者群体和正常对照受试者在即时和延迟记忆能力方面的细微差异。
