Introduction: Prospective memory (PM) is the ability to remember the intention to perform an action in the future. Following mild traumatic brain injury (mTBI), the brain structures supporting such PM may be compromised. PM is essential for remembering activities specific to TBI survivors that promote recovery, such as following doctors' orders, taking necessary medications, completing physical rehabilitation exercises, and maintaining supportive social relationships. Since the year 2000, more than 315,897 US Service Members are reported to have sustained an mTBI1, yet little has been done to address possible PM concerns. Therefore, identifying impaired PM and interventions that may ameliorate such deficits is important. The primary aim of this study was to determine whether task encoding using implementation intentions leads to better PM performance than encoding using rote rehearsal in Service Members with mTBI (n = 35) or with bodily injuries but no TBI (n = 8) at baseline and 6 months later. Materials and Method: Participants were randomized to one of the two encoding conditions. They were asked to remember to complete a series of four tasks over the course of a 2-hour event-related potential session and to contact a staff member during a specified 2-hour window later that day. PM performance was assessed based on completion of each task at the appropriate time. IRB approval was obtained from The Catholic University of America, Walter Reed National Military Medical Center, and Ft. Belvoir Community Hospital. Results: Service Members with mTBI using implementation intentions outperformed those using rote rehearsal. The effect of injury type and the interaction between encoding condition and injury type did not yield differences that were statistically significant. Conclusions: The results suggest that implementation intentions may be a useful PM remediation strategy for those who have sustained mTBI. Future research should validate these findings in a larger sample
The effect of initial planning on complex prospective memory was investigated using a virtual environment and a sample of healthy young adults (N = 34). Participants were assigned to either an initial planning or a control condition and were asked to complete a series of time-and event-based prospective memory tasks. The planning group completed the tasks more quickly and accurately than the control group. However, the total time spent, including both planning and task execution, was comparable for the two groups. Within the planning group, tasks that were planned were more likely to be completed than unplanned tasks, but inclusion of overly detailed information in the plans resulted in poorer performance. These results suggest that although initial planning can be beneficial to task completion, the complexity of a plan may contribute to decrements in performance.
Objective:The goal of this study was 2-fold, first, to compare decision making in behavioral variant frontotemporal dementia (bvFTD) patients and healthy adults using the Balloon Analog Risk Task (BART), and, second, to identify the regions of gray matter atrophy associated with bvFTD patients' BART performance. Background:Stimulus-reinforcement learning is required to evaluate the results of previously chosen actions to improve future decisions. Although there is a well established literature suggesting altered decision making in FTD patients and data from lesion studies suggest orbitofrontal cortex (OFC) involvement in decision making, there is very little research looking at the brain correlates of decision making in FTD populations specifically. Method:Twenty-seven bvFTD patients and 19 age-matched and education-matched normal controls completed the BART. Voxel-based morphometry analysis was performed on the magnetic resonance imaging scans of a subset of patients. Results:Compared with healthy controls, the bvFTD patients did not learn and pumped less to inflate a balloon to receive a reward, indicating altered stimulus-reinforcement learning. The voxel-based morphometry analysis indicated that bvFTD patients' impaired BART performance was related to atrophy in the right lateral OFC. Conclusions:The right lateral OFC is crucial for stimulus-reinforcement learning required for the adjustment of behavior under changing reward contingencies.
Prospective memory (PM), which is the ability to remember to carry out actions that are planned for the future, plays an important role in professional and social life as well as in activities of daily living. This study examined PM performance among adults with multiple sclerosis (MS) and evaluated the efficacy of a mnemonic strategy, implementation intentions. Compared to controls, adults with MS were impaired on PM, both in terms of acting when encountering the correct circumstances (prospective component) and in terms of remembering the correct action to perform (retrospective component). The prospective-component deficit was greater for tasks that depended on more resource-demanding cognitive processes and smaller on tasks that could be performed more automatically. Use of implementation intentions improved MS-group performance on the prospective component, particularly on the more resource-demanding tasks, consistent with the explanation that implementation intentions improved performance by allowing the use of more automatic processes to perform these PM tasks. Implications for providing environmental support to encourage the use of mnemonic strategies are discussed.
Skills are generally acquired by learning a set of facts about a task and developing appropriate procedures. For example, to learn to fly a plane, you first might learn the function of the flight controls and their locations and then practice manipulating the controls in appropriate sequences for a flight procedure. The practice part of training often cannot be done in the actual situation; a plane may not be available or the cost of the plane and an instructor on a regular basis may be prohibitive. In these situations, training is provided in alternative environments, or simulators, that mimic the target task. Designing simulators that will produce effective training has been a long-standing goal for those involved in skill acquisition, and the success of such simulations is generally measured by the effectiveness of subsequent performance on the actual task-the degree of “transfer” from the simulated to the real environment.
The training of composite skills requiring differential responding to a large set of stimuli raises issues about how to break down the whole task into parts and which parts should be trained first. Components of Morse code reception skill were identified, separated, and used to test whether initial training on a difficult part was more effective than initial training on an easy part. Initial training on a difficult subset of stimuli and on a difficult subtask both yielded disadvantages rather than the advantage implied by recent findings with different tasks. Incremental training should begin with the part yielding the most effective strategic skills, which appear to depend on characteristics of the task. In both present experiments, easy initial training led to adoption of an effective unitization strategy for representing codes. The hypothesis that procedural reinstatement at delayed testing leads to better retention was supported and extended.
Retention of spatial knowledge was compared after acquisition using virtual reality (VR), a map, and a real building. Participants were trained to navigate a route and to note the locations of landmarks. Two weeks later they were tested on their ability to navigate the route and to point to the landmarks they had learned. They were tested in either an aligned or contra-aligned orientation. The orientation specificity for VR observed immediately after training in our previous experiment (Clawson, Miller, Knott, & Sebrechts, 1998) was magnified after retention. On the route test, the VR group performed better than the map group, but only when tested in the aligned orientation. On the survey test, the VR group was less accurate than the map or real building groups, especially in the contra-aligned condition. Potential cognitive and perceptual causes of this orientation specificity are discussed.
Three experiments explored aspects of virtual reality (VR) that may influence its utility for training in navigating architectural spaces. Taken together, these experiments suggest that the utility of virtual reality depends on characteristics of the user-virtual environment interface. In experiments testing the importance of movement control, full participant control of rotational and forward movement in VR led to nearly optimal training on a medium-sized building, but limited control in VR was worse than no control. Transparent walls, a VR possibility that goes beyond real-world options, were beneficial during training and on a direct measure of learning spatial layouts. Finally, in an experiment examining both training and transfer, VR training was similar to real-world training, and was quicker and transferred better to navigating a real-world building than floor-plan training. However, this held only when the testing route was traveled in the trained direction.
The prospect of individual virtual reality workstations pose new challenges for design of an interface that can provide an immersive experience in a relatively confined space. CyberSeat II is one strategy that provides a compelling virtual environment (VE) under these circumstances. This approach, as well as the tools for assessing spatial location in and out of a VE, are described.
Peter Polson合作论文数Indiana University2