Reconsolidation: a brief history, a retrieval view, and some recent issues

This review briefly traces some of the history of the phenomenon of what has come to be called "reconsolidation." The early findings of retrograde amnesia for an old but reactivated memory led to several interesting but largely behaviorally oriented studies. With only a few sporadic exceptions, research in the area languished until about 2000, when several articles caught the attention of the neuroscience community and led to a number of studies examining the phenomenon at several different levels of analysis. We consider several of the current issues generated by those studies, present a retrieval based model that may account for some findings, and indicate some possible new directions on this topic.     

Is the context shift effect a case of retrieval failure? The effects of retrieval enhancing treatments on forgetting under altered stimulus conditions in rats

This series of experiments sought to clarify the role of retrieval failure in forgetting that results from a change in context between training and testing (the context shift effect [CSE]). Because spontaneous forgetting (SF) is generally considered to reflect a retrieval failure, the effects of three manipulations known to alleviate SF were examined on forgetting due to an explicit shift in context at a short delay (24 hr). Pretest exposure to a reminder treatment involving the reinforcer from training (Experiment 1), pretest amphetamine administration (Experiment 2), and overtraining (Experiment 3) alleviated both SF and the CSE, supporting the view that the CSE reflects a retrieval deficit. Implications for the context change account of SF are discussed.     

-Cycloserine: Effects on Long-Term Retention of a Conditioned Response and on Memory for Contextual Attributes

-Cycloserine (DCS), a partial agonist of the glycine recognition site of the N-methyl -aspartate receptor, has beneficial effects on learning and memory. In order to investigate its potential to influence learning and memory of both the response and the stimulus attributes of training, male Sprague-Dawley albino rats were trained in a one-trial inhibitory avoidance task following an acute intraperitoneal injection of DCS (3 mg/kg) or an equal volume of saline. In order to measure memory for stimulus attributes, testing involved a context shift paradigm, in which subjects are tested in either the environment of training or a different one. Good memory for the contextual attributes of training is indicated by poor performance in the alternate context. Retention was assessed either 1, 7, or 14 days after training. At 1 day, Saline subjects were affected by a change in context, while DCS subjects were not. In subjects tested 1 week following training, Saline subjects were no longer affected by a change in context, in that they performed the avoidance response in both contexts. This indicates the forgetting of stimulus attributes in Saline subjects. DCS subjects did show the context shift effect at 1 week, indicating the retention of stimulus attributes. Finally, Saline subjects demonstrated the context shift rebound at 14 days, while DCS subjects performed equivalently in both contexts. Taken together, these data suggest that DCS may enhance retention of fear and slow the forgetting of stimulus attributes.     

Assessing Culturally Different Students for Attention Deficit Hyperactivity Disorder Using Behavior Rating Scales

Behavior rating scales are commonly used in the assessment of attention deficit-hyperactivity disorder (ADHD). However, there is little information available concerning the extent to which scales are valid with culturally different students. This study explored the use of the ADHD-IV Rating Scale School Version with male Caucasian (CA) and African American (AA) students from ages 5 to 18 years. Teachers rated AA students higher on all symptoms across all age groups. LISREL analysis indicated that scale does not perform identically across groups. This was supported by the results of multidimensional scaling with suggested that there is a different relation between items across groups. Implications for research and practice are discussed.     

Time-dependent changes in inaccessible memory

The present experiment examined whether forgetting of contextual attributes—the loss of discriminability of background stimulus features over time—also occurs when a memory remains inaccessible (amnestic) during the retention interval. To examine this issue, rats received an acute hypothermia treatment that caused reversible anterograde amnesia for a passive-avoidance task and were tested 1 or 7 days later in either the same or a different context. At the short retention interval, the subjects discriminated between the contexts, as evidenced by the finding that reversal of amnesia occurred only in the training context. However, at the 7-day interval, recovery of the avoidance response was induced in either context, reflecting the forgetting of differentiating characteristics. These findings indicate that inaccessible memory remains susceptible to processes of modification and distortion that typically influence intact memories.     

成人日常问题解决的老化研究

日常问题解决能力是近十几年来老年心理学中研究比较活跃的一个领域。本文介绍了有关日常问题解决研究的四种理论,即心理测量的智力内隐理论、形式后思维的辨证思维理论、信息加工理论和社会认知与智慧理论,及其初步的研究成果,并进一步指出在理论上整合和在实践中开展干预的研究方向。     

Reduction of ontogenetic retention decrements in rats by pretraining stressful experiences.

Pretraining stressful experiences, either similar to or qualitatively different from the conditioning unconditioned stimulus, reduced ontogenetic retention decrements without directly influencing response acquisition. Rats that received pretreatment with footshock, hypthermia, or restraint on Days 16, 17, and 18 of age showed substantially improved long-term retention of conditioned fear learned at 20 days of age. It was also found that preshock enhanced retention of both an appetitive approach response and punishment of the approach response. Several experiments involving extinction and undertraining manipulations indicated that the facilitation of retention was not directly attributable to acquisition strength.     

Visual-field asymmetries in letter recognition: evidence for asymmetry in early visual registration

Two experiments on visual-field differences in tachistoscopic letter recognition are described. In the first, a bright pre-exposure field with a black fixation point was used, and the conventionally expected dominance of the right visual field was found. However, a large number of "blank" trials were observed, in which subjects completely failed to detect the presence of the flashed target. These "blanks" were themselves significantly asymmetric between visual fields, suggesting that asymmetry in early stimulus registration may play an unsuspected role in typical measures of cerebral asymmetry in recognition accuracy. This was confirmed in a second experiment in which use of dark pre-exposure fields eliminated "blanks" and led to higher over-all accuracy, with no visual-field differences. Implications for interpretation of laterality data with normal subjects are discussed.