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PubMed1978

An assessment of informative-counseling procedures for cleft palate children.

32 children with cleft palate and their mothers were interviewed for the purpose of learning what information they had about cleft and cleft management. Their responses were compared with standards specified by eight cleft palate specialists from four disciplines. The findings indicate that the specialists were somewhat inconsistent in what they expected the families to know about clefts and in their routine counseling procedures to provide the information. In general, the mothers had appropriate knowledge about clefts but predicted that their children knew more about clefts and cleft management than was actually the case. The children had less than adequate information about the general impact of a cleft, the etiology of clefts, the rationale for cleft management they had received, and future management of their problem. The results of the study indicate the need or more systematic procedures for providing information to the child with a cleft. The results also suggest the need for additional research about the general counseling process.

Adolescent↗
PubMed2001

Behavioral planning in the prefrontal cortex.

Recent studies have presented evidence that the prefrontal cortex plays a crucial role in every aspect of the cognitive processes necessary for behavioral planning: processing and integration of perceived or memorized information, associative learning, reward-based behavioral control, behavioral selection/decision-making and behavioral guidance. We propose that the creation of novel information is the means by which the prefrontal cortex operates to achieve executive control over behavioral planning. The prefrontal cortex is the site of operation of nodal points, where neural circuits integrate currently available or memorized information to generate the information that is necessary to perform an action. The prefrontal cortex also regulates the flow of information through multiple nodes to meet behavioral demands.

Animals↗
PubMed2004

Episodic memory impairment in bipolar disorder and obsessive-compulsive disorder: the role of memory strategies.

BACKGROUND: There is evidence that individuals with bipolar disorder exhibit neuropsychological impairments not only during mood episodes but also when they are euthymic. One of the most consistently reported cognitive problems in euthymic individuals with bipolar disorder is an impairment in verbal episodic memory. Verbal learning and memory depend on individuals' ability to organize verbal information appropriately during learning. The purpose of the present study was (i) to determine whether episodic memory impairment in euthymic individuals with bipolar disorder is mediated by impairments in organization of verbal information during learning and (ii) to compare the characteristics of memory impairment in bipolar disorder with that previously found in obsessive-compulsive disorder (OCD). METHODS: Study participants were 30 individuals with DSM-IV bipolar I disorder (BP-I), 30 individuals with DSM-IV OCD and 30 normal control participants matched for age, gender and education. Participants completed the California Verbal Learning Test (CVLT), a well-established measure of verbal learning and memory that enables assessment of verbal organization strategies during learning. RESULTS: Compared with control subjects, both BP-I and OCD participants showed impaired performance in long-delayed free recall and verbal organization strategies during learning. BP-I participants showed greater long-delay free recall difficulties but not greater verbal organization difficulties during learning than OCD participants. For OCD participants, the long-delay recall impairment was mediated by difficulties using verbal organizational strategies during learning. In contrast, the group difference in long-delayed free recall between BP-I and control participants remained significant even when semantic clustering was introduced as a mediator. This indicated that BP-I participants' long-delayed free recall difficulties were mediated to a lesser extent by difficulties using verbal organizational strategies than for OCD participants. CONCLUSIONS: Verbal episodic memory problems in individuals with bipolar I disorder and OCD are mediated to different degrees by difficulties using semantic clustering encoding strategies compared with control participants.

Adult↗
PubMed2003

The nucleus basalis and memory codes: auditory cortical plasticity and the induction of specific, associative behavioral memory.

Receptive field (RF) plasticity develops in the primary auditory cortex (ACx) when a tone conditioned stimulus (CS) becomes associated with an appetitive or aversive unconditioned stimulus (US). This prototypical stimulus-stimulus (S-S) association is accompanied by shifts of frequency tuning of neurons toward or to the frequency of the CS such that the area of best tuning of the CS frequency is increased in the tonotopic representation of the ACx. RF plasticity has all of the major characteristics of behavioral associative memory: it is highly specific, discriminative, rapidly induced, consolidates (becomes stronger and more specific over hours to days) and can be retained indefinitely (tested to two months). Substitution of nucleus basalis (NB) stimulation for a US induces the same associative RF plasticity, and this requires the engagement of muscarinic receptors in the ACx. Pairing a tone with NB stimulation actually induces specific, associative behavioral memory, as indexed by post-training frequency generalization gradients. The degree of acquired behavioral significance of sounds appears to be encoded by the number of neurons that become retuned in the ACx to that acoustic stimulus, the greater the importance, the greater the number of re-tuned cells. This memory code has recently been supported by direct neurobehavioral tests. In toto, these findings support the view that specific, learned auditory memory content is stored in the ACx, and further that this storage of information during learning and the instantiation of the memory code involves the engagement of the nucleus basalis and its release of acetylcholine into target structures, particularly the cerebral cortex.

Acetylcholine↗
PubMed1998

Campus courtship behavior and fear of human immunodeficiency virus infection by university students.

Data were collected by telephone from a random sample of 762 students at the University of Northern Colorado to examine students' fear of human immunodeficiency virus (HIV) infection and their suggested approaches to prevent the spread of the disease. Of the 762 students interviewed, 177 (24.1%) believed that HIV/acquired immunodeficiency syndrome (AIDS) was a threat to socialization on campus. Fourteen percent of the female students considered HIV/AIDS to be a threat compared with 10.1% of their male counterparts. Among all interviewees, 573 (76.7%) believed HIV/AIDS was a threat to romance at the university. Statistically significant association was found between the perceived fear of HIV/AIDS and gender. With regard to actual sexual intercourse, 86.4% of the students believed that HIV/AIDS was a major threat compared with 13.6% who did not. The association between the perception about HIV/AIDS as a threat to on-campus sexual intercourse and gender was statistically significant. Of the entire sample, 69.3% suggested abstinence as an approach to avoid HIV infection. Slightly more than 24% suggested condom use. Eighteen (10.8%) students advised that sexual contact should be only with a trusted partner. More information about HIV/AIDS should be provided to all students, especially women, in institutions of higher learning. More information can reduce the fear associated with this deadly disease.

Acquired Immunodeficiency Syndrome↗
PubMed2006

The value of basic science in clinical diagnosis.

BACKGROUND: The role of basic science knowledge in clinical diagnosis is unclear. There has been no experimental demonstration of its value in helping students recall and organize clinical information. This study examines how causal knowledge may lead to better recall and diagnostic skill over time. METHOD: Undergraduate medical students learned either four neurological or rheumatic disorders. One group learned a basic science explanation for the symptoms. The other learned epidemiological information. Both were then tested with the same set of clinical cases immediately after learning and one week later. RESULTS: On immediate test, there was no difference in accuracy (70% for both groups). However, one week later, performance in the epidemiology group dropped to 51%; the basic science group only dropped to 62%. CONCLUSIONS: Basic science knowledge relating causal knowledge to disease symptoms can improve diagnostic accuracy after a delay.

Education, Medical, Undergraduate↗
PubMed2000

Managing the learning and work of new information technology users.

The information technology revolution has transformed work from modest-paced serial processes to complex, fast-paced networked ones that depend not only on the technology but also on skilled and effective users of the technology. This evolution has woven a complex quilt of interdependencies among new information technologies, new users of those technologies, new skills required, new information management policies and procedures, and new opportunities. We must impose a new structure for managing the learning and work of new users, their tolerance of complexity and continuous learning, value-added usability, minimization of human error, and new support services for deployment, administration, and help.

Computer User Training↗
PubMed1992

What makes information important and its influence on learning in self-directed study.

This study investigated what makes text-based information important and what is its influence on learning. College students studied an expository text following their own self-directed study procedures. Data from Exp. 1 (n = 60) and Exp. 2 (n = 40) showed that information was considered important if it (a) began and ended text, (b) began a paragraph, (c) appeared at somewhat equal intervals in text, and (d) contained enumerations of concepts. Subjects recalled information that (a) began the text and (b) contained examples of enumerations. It appeared that text-based variables established what was important and this influenced learning. Implications for the selective attention hypothesis and its volume-of-attention corollary, the cycles hypothesis, and the slot-filling hypothesis are discussed.

Achievement↗
PubMed2025

Refining sequence-to-activity models by increasing model resolution.

Decoding the cis-regulatory syntax that controls gene expression is essential for improving our understanding of cell differentiation and disease. To identify regulatory motifs and their regulatory syntax, deep learning based sequence-to-activity (S2A) models learn transcription factor binding motifs and their combinations from DNA sequence by modeling measured chromatin accessibility. Previously, we developed AI-TAC, a S2A model that predicts chromatin accessibility across various immune cell types in multi-task fashion, effectively decoding the regulatory syntax underlying immune cell differentiation. While ATAC-seq is commonly used to measure regional accessibility, it also provides high-resolution profiles, the distribution of Tn5 insertion sites, that offer additional insights into the precise location and strength of TF binding sites. Here we demonstrate that modeling ATAC-seq profiles alongside accessibility consistently improves predictions of differential chromatin accessibility across cell types. Moreover, we also find that multi-task learning across related immune cell types consistently outperforms single-task models. To understand what additional information bpAITAC learns from ATAC-seq profiles, we systematically compare sequence attributions from models trained with and without ATAC-seq profiles. We identify novel motifs with strong effect sizes that emerge only when profile data is included. Our findings suggest that modeling ATAC-seq at base-pair resolution enables the model to learn a more nuanced and sensitive representation of the cis-regulatory syntax driving immune cell-specific chromatin landscapes.

ATAC-seq↗
PubMed2006

One-shot learning of object categories.

Learning visual models of object categories notoriously requires hundreds or thousands of training examples. We show that it is possible to learn much information about a category from just one, or a handful, of images. The key insight is that, rather than learning from scratch, one can take advantage of knowledge coming from previously learned categories, no matter how different these categories might be. We explore a Bayesian implementation of this idea. Object categories are represented by probabilistic models. Prior knowledge is represented as a probability density function on the parameters of these models. The posterior model for an object category is obtained by updating the prior in the light of one or more observations. We test a simple implementation of our algorithm on a database of 101 diverse object categories. We compare category models learned by an implementation of our Bayesian approach to models learned from by Maximum Likelihood (ML) and Maximum A Posteriori (MAP) methods. We find that on a database of more than 100 categories, the Bayesian approach produces informative models when the number of training examples is too small for other methods to operate successfully.

Algorithms↗
PubMed2002

Emerging patterns in tumor systems: simulating the dynamics of multicellular clusters with an agent-based spatial agglomeration model.

Brain cancer cells invade early on surrounding parenchyma, which makes it impossible to surgically remove all tumor cells and thus significantly worsens the prognosis of the patient. Specific structural elements such as multicellular clusters have been seen in experimental settings to emerge within the invasive cell system and are believed to express the systems' guidance toward nutritive sites in a heterogeneous environment. Based on these observations, we developed a novel agent-based model of spatio-temporal search and agglomeration to investigate the dynamics of cell motility and aggregation with the assumption that tumors behave as complex dynamic self-organizing biosystems. In this model, virtual cells migrate because they are attracted by higher nutrient concentrations and to avoid overpopulated areas with high levels of toxic metabolites. A specific feature of our model is the capability of cells to search both globally and locally. This concept is applied to simulate cell-surface receptor-mediated information processing of tumor cells such that a cell searching for a more growth-permissive place "learns" the information content of a brain tissue region within a two-dimensional lattice in two stages, processing first the global and then the local input. In both stages, differences in microenvironment characteristics define distinctions in energy expenditure for a moving cell and thus influence cell migration, proliferation, agglomeration, and cell death. Numerical results of our model show a phase transition leading to the emergence of two distinct spatio-temporal patterns depending on the dominant search mechanism. If global search is dominant, the result is a small number of large clusters exhibiting rapid spatial expansion but shorter lifetime of the tumor system. By contrast, if local search is dominant, the trade-off is many small clusters with longer lifetime but much slower velocity of expansion. Furthermore, in the case of such dominant local search, the model reveals an expansive advantage for tumor cell populations with a lower nutrient-depletion rate. Important implications of these results for cancer research are discussed.

Algorithms↗
PubMed2001

Visual discrimination learning in the water maze: a novel test for visual acuity.

Learning about space, the environment and specific objects comprising three-dimensional arrangements requires processing of visual information. As learning and memory experiments in mammals rely heavily on normal processing of visual cues, drug-induced disruption of acquisition learning or memory formation necessitates the important control for visual acuity. A popular task used frequently for rats is the Morris water maze. However, previously used visual tasks in the water maze only control for gross visual disturbances. Here we describe a new training procedure enabling visual acuity to be tested in the water maze. Animals were trained to discriminate between two cue cards containing a pattern of vertical black and white stripes. Cards were presented in two adjacent quadrants separated by a barrier with the escape platform located in front of the smaller stripes (1 cm wide). Once 80% correct responses were attained, the wider cue card (normally 5 cm wide stripes) was randomly changed to gratings of 1,2,3,4,5, and 10 cm width. Animals learned the discrimination with acuity of 1.5 c/deg. A detailed analysis of the swim patterns further suggests that, independent of the grating used, animals make a choice immediately after release and swim along the walls towards the cue. In a further acuity test taken a few weeks later when animals were given saline infusions, performance was better than in the first test suggesting an effect of learning. This novel test may prove useful in determining subtle drug-induced deficits in visual acuity that may contribute to disruption of spatial performance in the water maze.

Animals↗
PubMed2005

Age, ability, and the role of prior knowledge on the acquisition of new domain knowledge: promising results in a real-world learning environment.

Prior knowledge, fluid intelligence (Gf), and crystallized intelligence (Gc) were investigated as predictors of learning new information about cardiovascular disease and xerography with a sample of 199 adults (19 to 68 years). The learning environment included a laboratory multimedia presentation (high-constraint-maximal effort), and a self-directed at-home study component (low-constraint-typical performance). Results indicated that prior knowledge and ability were important predictors of knowledge acquisition for learning. Gc was directly related to learning from the video for both domains. Because the trajectory of Gc stays relatively stable throughout the life span, these findings provide a more optimistic perspective on the relationship between aging and learning than that offered by theories that focus on the role of fluid abilities in learning.

Adult↗
PubMedDate not supplied

Learning in post-traumatic amnesia following extremely severe closed head injury.

Verbal and spatial tests of learning were administered in five repeated sessions to nine subjects who were in post-traumatic amnesia (PTA) following extremely severe closed head injuries. PTA was operationally defined as having a score of 75 or less on the Galveston Orientation and Amnesia Test. Subjects showed no ability to learn verbal information (free recall and recognition of a word list) but showed some savings of spatial location information over the first three sessions. Results were interpreted as suggestive of a primarily passive mode of learning during PTA, regardless of the nature of the material to be learned.

Adult↗
PubMed1996

Data-driven approaches to decision making in automated tumor grading. An example of astrocytoma grading.

OBJECTIVE: To compare four data-driven approaches to automated tumor grading based on morphometric data. Apart from the statistical procedure of linear discriminant analysis, three other approaches from the field of neural computing were evaluated. STUDY DESIGN: The numerical basis of this study was computed tomography-guided, stereotactically obtained astrocytoma biopsies from 86 patients colored with a combination of Feulgen and immunhistochemical Ki-67 (MIB1) staining. In these biopsies the cell nuclei in four consecutive fields of vision were evaluated morphometrically and the following parameters determined: relative nuclei area, secant lengths of the minimal spanning trees and relative volume-weighted mean nuclear volumes of the proliferating nuclei. RESULTS: Based on the analysis of these morphometric features, the multivariate-generated HOM grading system provides the highest correct grading rates (> 90%), whereas the two widely employed qualitative histologic grading systems for astrocytomas yield correct grading rates of about 60%. For automated tumor grading all approaches yield similar grading results; however, back-propagation networks provide reliable results only following an extensive training phase, which requires the use of a supercomputer. All other neurocomputing models can be run on simple UNIX workstations (AT&T, U.S.A). CONCLUSION: In contrast to discriminant analysis, backpropagation and Kohonen networks, the newly developed neural network architecture model of self-editing nearest neighbor nets (SEN3) provides incremental learning; i.e., the training phase does not need to be restarted each time when there is further information to learn. Trained SEN3 networks can be considered ready-to-use knowledge bases and are appropriate to integrating further morphometric data in a dynamic process that enhances the diagnostic power of such a network.

Algorithms↗
PubMedDate not supplied

School is fun at recess: informal analyses of written language for students with learning disabilities.

The purpose of an informal analysis of written language is to identify what writers can do as well as what they find difficult about writing. This article reviews the varied components of written language, suggests informal means for assessment, and summarizes the cognitive and linguistic factors that influence varied aspects of writing performance. Two informal evaluation scales are presented that stress the interconnection between oral and written language processes.

Child↗