Word-processing training and retraining: effects of adult age, experience, and interface

Novice (Experiment 1) and experienced (Experiment 2) young, middle-aged, and older adults learned a new word-processing application in keystrokes, menus, or menus-plus-icons interface conditions. Novices showed strong age differences in the time to complete the 3-day tutorial and in declarative and procedural tests of word-processing knowledge. Menus and menus-plus-icons were superior to keystrokes condition. though interface did not interact with age. Experienced users showed age-related slowing in learning rate but minimal age differences in test performance when retrained on a new word-processing program. Age and computer experience accounted for much of the variance in both learning time and word-processing performance; interface type, speed of processing, and spatial generation ability made additional contributions. Experience interacted with age to predict performance. Implications for training and retraining older workers are discussed.     

Sequential Aiming with Two Limbs and the One-Target Advantage

Movement times to the first target in a 2-target sequence are typically slower than in 1-target aiming tasks. The 1-target movement time advantage has been shown to emerge regardless of hand preference, the hand used, the amount of practice, and the availability of visual feedback. The authors tested central and peripheral explanations of the 1-target advantage, as postulated by the movement integration hypothesis, by asking participants to perform single-target movements, 2-target movements with 1 limb, and 2-target movements in which they switched limbs at the first target. Reaction time and movement time data showed a 1-target advantage that was similar for both 1- and 2-limb sequential aiming movements. This outcome demonstrates that the processes underlying the increase in movement time to the 1st target in 2-target sequences are not specific to the limb, suggesting that the 1-target advantage originates at a central rather than a peripheral level.     

Construct validity of the California Verbal Learning Test--Children's Version (CVLT-C) after pediatric traumatic brain injury

The purpose of this study was to determine the latent structure of the California Verbal Learning Test--Children's Version (CVLT-C; D. Delis, J. Kramer, E. Kaplan, & B. Ober, 1994) in a sample of 175 children with traumatic brain injury (TBI). Maximum-likelihood confirmatory factor analyses were performed to test 6 competing hypothetical models for fit and parsimony. A 4-factor model consisting of Attention Span, Learning Efficiency, Delayed Recall, and Inaccurate Recall provided the best fit to the data. The results support the construct validity of the CVLT-C in children with TBI and suggest that a multifactorial interpretation of quantitative indexes from this instrument is appropriate for clinical practice.     

The dual role of vision in sequential aiming movements

Previous research has demonstrated that movement times to the first target in sequential aiming movements are influenced by the properties of subsequent segments. Based on this finding, it has been proposed that individual segments are not controlled independently. The purpose of the current study was to investigate the role of visual feedback in the interaction between movement segments. In contrast to past research in which participants were instructed to minimize movement time, participants were set a criterion movement time and the resulting errors and limb trajectory kinematics were examined under vision and no vision conditions. Similar to single target movements, the results indicated that vision was used within each movement segment to correct errors in the limb trajectory. In mediating the transition between segments, visual feedback from the first movement segment was used to adjust the parameters of the second segment. Hence, increases in variability that occurred from the first to the second target in the no vision condition were curtailed when visual feedback was available. These results are discussed along the lines of the movement constraint and movement integration hypotheses.     

Intra-habenular injection of 6-hydroxydopamine produces impaired acquisition of DRL operant behavior

The anatomical connections of the habenula complex indicate it provides a relay between limbic forebrain and midbrain. Somewhat paradoxically, consequences of nonspecific lesion of the habenula are ambiguous with little change in basic response evident within simple behavioral paradigms. However, the potential functional importance for this relay has more recently been indicated by the demonstration of deficits in the ability of lesioned animals to alter behavior appropriate to both internal and external stimuli in more demanding behavioral tasks. Doubts concerning the importance of the habenula remain because of the large number of descending fibers of passage through the habenula. To provide more substantive evidence, 6-hydroxydopamine was injected into the habenula of rats to provide more limited lesion of catecholaminergic terminals. Animals were subsequently trained on an operant DRL 20-s schedule for which deficits have been reported following nonspecific lesion of the habenula. Lesioned animals showed a tendency to overrespond and were significantly less efficient on the schedule with decreased number of reinforcements received relative to controls. While the neurotoxic lesion procedure used does not differentiate noradrenergic and dopaminergic damage, the importance of intact catecholaminergic systems within the habenula for effective DRL acquisition is consistent with the suggested importance of the habenula for feedback regulation of dopamine within the ventral tegmental area through ascending dopamine fibers to the habenula.     

Expansion of Genetic Services Utilizing a General Genetic Counseling Clinic

We established a general genetic counseling clinic (GCC) to help reduce long wait times for new patient appointments and to enhance services for a subset of patients. Genetic counselors, who are licensed in Tennessee, were the primary providers and MD geneticists served as medical advisors. This article describes the clinic referral sources, reasons for referral and patient dispositions following their GCC visit(s). We obtained patients by triaging referrals made to our medical genetics division. Over 24 months, our GCC provided timely visits for 321 patients, allowing the MD geneticists to focus on patients needing a clinical exam and/or complex medical management. Following their GCC visit(s), over 80 % of patients did not need additional appointments with an MD geneticist. The GCC allowed the genetic counselor to spend more time with patients than is possible in our traditional medical genetics clinic. Patient satisfaction surveys (n?=?30) were very positive overall concerning the care provided. Added benefits for the genetic counselors were increased professional responsibility, autonomy and visibility as health care providers. We conclude that genetic counselors are accepted as health care providers by patients and referring providers for a subset of clinical genetics cases. A GCC can expand genetic services, complement more traditional genetic clinic models and utilize the strengths of the genetic counselor health care provider.     

Sequential aiming with one and two limbs: Effects of target size

It is well reported that movement times to the first target in a two-target sequence are slower than when a single target response is required. This one-target advantage has been shown to emerge when the two-target sequence is performed with the same limb and when the first and second segments within the sequence are performed with different limbs (i.e., when there is a switch between limbs at the first target). The present study examined the functional dependency between response segments in both single and two limb sequential aiming by varying the accuracy demands at the first and second target. Results revealed that, for both one and two limb conditions, the one-target advantage was present with large first targets but not with small first targets. Additionally, when the first target was large and the second target was small, spatial variability at the first target was significantly less (or constrained more) in both one and two limb conditions compared to conditions requiring only a single target response. These findings suggest that similar principles underlie the one-target advantage in both single and two limb sequential movements.