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PubMed1989

[Application of the segmented arch technique in adult patient].

The segmented arch technique has been developed with the three primary objectives; (1) force control over active and reactive teeth, (2) reduction in the number of chair hours required to treat a case, and (3) minimization of patient cooperation. The author experienced the efficiency and superiority of the segmented arch technique through the treatment of the Korean adult patient. With the possibility of accurately measuring the forces and moments delivered to tooth during orthodontic therapy, not only is it possible to improve the quality of orthodontic tooth movement, but it is also possible to learn about the nature of optimal forces that are needed clinically. A number of mechanisms have been described for initial levelling, deep overbite correction, anterior retraction, root movement and occlusal seating.

Adult↗
PubMed1996

Informed consent: the nurse's dilemma.

The author builds upon the concept of informed consent whereby the patient agrees to undergo experimental medical procedures. Ideally, the doctor will inform the patient fully on the proposed treatment so as to assure the patient's right to participate intelligently and freely in the decisions regarding his treatment. The nurse is drawn into the doctor-patient relationship in cases where the patient seeks her counsel because he feels insufficiently informed by the doctor, or because the nurse becomes aware of inadequacies in the information-giving process. She is then faced by the nurse's dilemma: a conflict between the loyalties she owes to her patient and to her physician team mate. A work sheet is presented which can help the nurse decide upon the proper course of action in solving this dilemma, guided by her personal and professional beliefs and by specific ethical concepts in the Code for Nurses. Solution of the dilemma and attainment of informed consent requires willing cooperation between doctor and nurse. Both can develop the skills for imparting information to the patient under difficult conditions and for verifying its comprehension by the patient. Both must learn to respect the patient's decision and to temper their professional skills with sensitivity, a strong moral sense and a deep respect for their fellow human beings.

Decision Making↗
PubMed2002

Dissociations between categorization and similarity judgments as a result of learning feature distributions.

A dissociation between categorization and similarity was found by Rips (1989). In one experiment, Rips found that a stimulus halfway between a pizza and a quarter was categorized as a pizza but was rated as more similar to a quarter. Smith and Sloman (1994) discussed these results in terms of the role of necessary and characteristic features. In two experiments, participants had to learn to categorize novel artificial shapes composed of a nonsalient necessary feature combined with a salient characteristic feature. Participants categorized stimuli on the basis of a necessary feature, whereas their similarity judgments relied on characteristic features. The role of deep (essential) features in dissociations is considered. Results are discussed in terms of the differences between requirements of categorization and similarity judgments.

Humans↗
PubMed1996

Representations in learning new faces: evidence from prosopagnosia.

We report the performance of a prosopagnosic patient on face learning tasks under different encoding instructions (i.e., levels of processing manipulations). R.J. performs at chance when given no encoding instructions or when given "shallow" encoding instruction to focus on facial features. By contrast, he performs relatively well with "deep" encoding instructions to rate faces in terms of personality traits or when provided with semantic and name information during the study phase. We propose that the improvement associated with deep encoding instructions may be related to the establishment of distinct visually derived and identity-specific semantic codes. The benefit associated with deep encoding in R.J., however, was found to be restricted to the specific view of the face presented at study and did not generalize to other views of the same face. These observations suggest that deep encoding instructions may enhance memory for concrete or pictorial representations of faces in patients with prosopagnosia, but that these patients cannot compensate for the inability to construct abstract structural codes that normally allow faces to be recognized from different orientations. We postulate further that R.J.'s poor performance on face learning tasks may be attributable to excessive reliance on a feature-based left hemisphere face processing system that operates primarily on view-specific representations.

Aged↗
PubMed1999

Human hippocampus associates information in memory.

The hippocampal formation, one of the most complex and vulnerable brain structures, is recognized as a crucial brain area subserving human long-term memory. Yet, its specific functions in memory are controversial. Recent experimental results suggest that the hippocampal contribution to human memory is limited to episodic memory, novelty detection, semantic (deep) processing of information, and spatial memory. We measured the regional cerebral blood flow by positron-emission tomography while healthy volunteers learned pairs of words with different learning strategies. These led to different forms of learning, allowing us to test the degree to which they challenge hippocampal function. Neither novelty detection nor depth of processing activated the hippocampal formation as much as semantically associating the primarily unrelated words in memory. This is compelling evidence for another function of the human hippocampal formation in memory: establishing semantic associations.

Adult↗
PubMed2000

New rules impact sedation and anesthesia care, Part 1.

Learn why the Joint Commission has revised its anesthesia care standards. The new standards incorporate four sedation levels: minimum sedation, moderate sedation/analgesia, deep sedation/analgesia, and anesthesia.

Anesthesia↗
PubMed2006

Impaired sequential egocentric and allocentric memories in forebrain-specific-NMDA receptor knock-out mice during a new task dissociating strategies of navigation.

The hippocampus is considered to play a role in allocentric but not in egocentric spatial learning. How does this view fit with the emerging evidence that the hippocampus and possibly related cortical areas are necessary for episodic-like memory, i.e., in all situations in which events need to be spatially or sequentially organized? Are NMDA receptor-dependent mechanisms crucial for the acquisition of spatiotemporal relationships? To address this issue, we used knock-out (KO) mice lacking hippocampal CA1 NMDA receptors and presenting a reduction of these receptors in the deep cortical layers (NR1-KO mice). A new task (the starmaze) was designed, allowing us to distinguish allocentric and sequential-egocentric memories. NR1-KO mice were impaired in acquiring both types of memory. Our findings suggest that memories composed of multiple spatiotemporal events require intact NMDA receptors-dependent mechanisms in CA1 and possibly in the deep cortical layers.

Animals↗
PubMed2002

Dopamine D2 receptors are present in prefrontal cortical afferents and their targets in patches of the rat caudate-putamen nucleus.

Glutamatergic neurons within the deep layers of the prefrontal cortex and dopaminergic neurons of the substantia nigra pars compacta preferentially terminate in patch-like regions within the caudate putamen nucleus (CPN). Activation of dopamine D2 receptors is known to potently modulate striatal glutamatergic transmission and may play a role in reward-based motor learning. To determine the cellular substrate for D2-mediated regulation of prefrontal corticostriatal transmission in striatal patches, we combined anterograde transport of biotinylated dextran amine (BDA) with immunogold-silver labeling of a D2 receptor antipeptide antiserum in rat brain. Injections centered in deep layers of the dorsal part of the anterior cingulate cortex, one of the prefrontal cortical regions, produced varicose axonal BDA labeling in a patch-like distribution in the dorsomedial CPN. Electron microscopy showed that in these patch compartments, BDA labeling was present exclusively in axons and terminals (total number = 581), 9% of which contained detectable D2-like immunoreactivity. Thirty percent of the BDA-labeled terminals formed asymmetric excitatory synapses with dendritic spine heads, and the remainder were without recognizable junctions. The recipient spines were unlabeled or contained immunogold-silver particles for D2 receptors. A few of the D2-labeled spines also received convergent, often nonsynaptic contact from D2-labeled terminals resembling dopaminergic afferents. In addition, the corticostriatal terminals often apposed spiny and nonspiny neuronal profiles that contained D2 labeling. These results suggest that dopamine D2 receptors are strategically positioned for presynaptic and postsynaptic modulation of prefrontal corticostriatal excitation of spiny neurons in striatal patches. The findings have direct implications for D2-mediated control of reward-related motor learning.

Animals↗
PubMed2004

Glutaric aciduria type I associated with learning disability.

The authors report a 7-year-8-months-old boy with glutaric aciduria type I who had associated dyslexia, dysgraphia and dyscalculia. The diagnosis of glutaric aciduria type I was confirmed on the basis of characteristic neuroimaging and biochemical findings. Axial T1-weighted magnetic resonance imaging scan of the brain showed fronto-temporal atrophy, open opercula and bat-wing dilatation of the sylvian fissures. Axial T[2]-weighted and FLAIR imaging showed hyperintense signal abnormality in both putamen and in the fronto-parietal deep white matter. Urinary aminoacidogram by thin layer chromatography revealed a generalized aminoaciduria. Urinary organic acid analysis by gas chromatography- mass spectroscopy revealed a marked excretion of glutaric acid. Psychoeducational testing was used to diagnose the learning disability. We postulate that the accumulation of glutaric acid and other metabolites was responsible for the child developing the associated learning disability.

Brain↗
PubMed1987

Strategies for visual word recognition and orthographical depth: a multilingual comparison.

We investigated the psychological reality of the concept of orthographical depth and its influence on visual word recognition by examining naming performance in Hebrew, English, and Serbo-Croatian. We ran three sets of experiments in which we used native speakers and identical experimental methods in each language. Experiment 1 revealed that the lexical status of the stimulus (high-frequency words, low-frequency words, and nonwords) significantly affected naming in Hebrew (the deepest of the three orthographies). This effect was only moderate in English and nonsignificant in Serbo-Croatian (the shallowest of the three orthographies). Moreover, only in Hebrew did lexical status have similar effects on naming and lexical decision performance. Experiment 2 revealed that semantic priming effects in naming were larger in Hebrew than in English and completely absent in Serbo-Croatian. Experiment 3 revealed that a large proportion of nonlexical tokens (nonwords) in the stimulus list affects naming words in Hebrew and in English, but not in Serbo-Croatian. These results were interpreted as strong support for the orthographical depth hypothesis and suggest, in general, that in shallow orthographies phonology is generated directly from print, whereas in deep orthographies phonology is derived from the internal lexicon.

Discrimination Learning↗
PubMed2005

Orthography as a handicap? A direct comparison of spelling acquisition in Danish and Icelandic.

Spelling of cross-linguistically very similar nonwords was compared in 115 Danish and 77 Icelandic children (primarily 3rd and 4th graders). Danish children made more errors than Icelandic children on word medial consonant doublets and on word initial consonant clusters, even when the groups compared were matched on simpler spelling tasks. These results suggest that the acquisition of phonemic encoding skills is slower in "deep" orthography such as Danish than in more "transparent" orthography such as Icelandic. The effect of orthography was expected for consonant doublets because of the relatively more complex sound-letter correspondences in Danish. For consonant clusters, however, sound-letter correspondences are perfectly regular in both languages. The study thus points to the conclusion that even the mastery of regular sound-letter correspondences may be delayed in deep orthography.

Adult↗
PubMed1991

Learning-specific differences in Purkinje-cell dendrites of lobule HVI (Lobulus simplex): intracellular recording in a rabbit cerebellar slice.

The cerebellum has been directly implicated in the associative learning exemplified by classical conditioning of the rabbit nictitating membrane response. Lesions of cerebellar lobule HVI (Lobulus simplex) can disrupt or even abolish classical conditioning. Electrical stimulation of inputs that converge at cerebellar lobule HVI and the deep cerebellar nuclei has been shown to support classical conditioning of the responses elicited by such stimulation. Here we report that intracellular recording in a slice of rabbit cerebellar lobule HVI revealed a conditioning-specific increase in the excitability of Purkinje-cell dendrites without significant changes in dendritic membrane potential or input resistance. The finding of a conditioning-specific change in lobule HVI lends support to the theory that associative learning involves local dendritic modification and provides further evidence for the involvement of the cerebellar cortex in classical conditioning of the rabbit's nictitating membrane response.

Animals↗
PubMed2025

CLINICAL AND COGNITIVE PHENOTYPING OF COPY NUMBER VARIANTS ASSOCIATED WITH NEURODEVELOPMENTAL DISORDERS FROM A MULTI-ANCESTRY BIOBANK.

Clinical biobanks with electronic health records (EHRs) linked to genotype data continue to expand yielding an opportunity to further characterize disease-relevant genomic risk factors, yet few recall-by-genotype studies from biobanks have been published to date. For example, copy number variants (CNVs) that significantly increase risk for multiple neurodevelopmental disorders (NDDs) and negatively affect neurocognition, may present in up to 2% of population cohorts, with public health implications for ascertaining NDD CNV carriers. From BioMe, a multi-ancestry biobank derived from the Mount Sinai healthcare system (New York, NY), 892 adult participants were recontacted for deep phenotyping, including 335 NDD CNV carriers as well as comparators, 217 individuals with schizophrenia and 340 controls. Clinical and cognitive assessments were administered to each participant. There was no disclosure of genetic information. Eight percent of recontacted biobank participants completed the study (30 NDD CNV carriers across 15 unique loci, 20 schizophrenia and 23 controls). The study sample had a mean age of 48.8 (10.2) years, was 66% female and of diverse ancestry, 36% African, 34% Hispanic, and 26% European. Overall, 70% of 30 NDD-CNV carriers harbored at least one neuropsychiatric or developmental phenotype, including 40% with mood or anxiety disorders. Further, 22 NDD CNV carriers were significantly impaired compared to controls on digit span backwards (Beta=-1.76, FDR=0.04) and digit span sequencing (Beta=-2.01, FDR=0.04), but higher performing than schizophrenia on verbal learning (Beta=4.5, FDR=0.05). Thirty NDD CNV carriers were successfully recruited from a multi-ancestry biobank, as well as healthy controls and low-functioning individuals with schizophrenia. Deep phenotyping corroborated past reports, while also identifying discordance with EHRs. Future recall-by-genotype studies may further benchmark the study design and elucidate feasibility.

Biobank↗
PubMed1993

Complications of laparoscopic pelvic lymph node dissection.

Intraoperative and postoperative complications were assessed in the first 372 patients undergoing laparoscopic pelvic lymph node dissection at 8 medical centers. In 16 patients laparoscopic node dissection could not be completed due to patient body habitus or technical difficulties. Of these aborted procedures 14 occurred during the initial 8 dissections at each institution. A total of 55 complications (15%) occurred: 14 were noted in the intraoperative and 41 in the postoperative period. Of these patients 13 required open surgical intervention for the treatment of a complication. Complications included vascular injury (11 patients), viscus injury (8), genitourinary problems (10), functional/mechanical bowel obstruction (7), lower extremity deep venous thrombosis (5), infection/wound problem (5), lymphedema (5), anesthetic complications (2) and obturator nerve palsy (2). Based on our experience, there is a significant learning curve associated with performing laparoscopic pelvic node dissection. However, with experience and adherence to laparoscopic surgical principles, the risk of complications may be minimized.

Adenocarcinoma↗
PubMed1992

Somatosensory Trigeminal Projections to the Inferior Olive, Cerebellum and other Precerebellar Nuclei in Rabbits.

We have analysed the pathways through which somatosensory information from the face reaches the inferior olive and the cerebellum in rabbits. We used wheatgerm agglutinin - horseradish peroxidase (WGA - HRP) to trace projections from all parts of the somatosensory trigeminal system to the olive, cerebellar cortex, the cerebellar deep nuclei and the pontine nuclei. Projections to the cerebellar cortex and inferior olive were verified using retrograde transport of WGA - HRP. Two regions of the inferior olive-the medial dorsal accessory olive and the ventral leaf of the principal olive-receive inputs from pars interpolaris (Vi) and rostral pars caudalis (Vc) of the spinal trigeminal nucleus and from the principal trigeminal nucleus (Vp). Another area in the caudal medial accessory olive receives inputs from rostral Vo (pars oralis of the spinal trigeminal nucleus), caudal Vi and Vc. There are trigemino-olivo-cortical inputs to lobule HVI via all these olivary areas and to the paramedian lobe via the principal olive only. Cerebellar cortex-lobules HVI, crus I and II, paramedian lobe and IX-receives direct mossy fibre inputs from Vp, Vo and rostral Vi. The pontine nuclei receive an input only from rostral Vi. We saw no trigeminal projections to other precerebellar nuclei or to the deep cerebellar nuclei. The concentration of face somatosensory cortical inputs, via several pathways, upon lobule HVI may underlie its important role in the regulation of learned and unlearned eyeblinks.

Journal Article↗
PubMed1987

Presidential address. Psychiatry today: the human dimensions.

Psychiatry finds itself today at the crossroads where science and humanism intersect. The history of our specialty includes some ignominious aspects, and many that are noble. Fear and loathing toward the depreciated imbecile and lunatic had at first to be overcome, and they were, and a humane and empathetic approach to patients eventuated. More than sympathy was called for--understanding was needed, and the methods of science have led to considerable such understanding: of causes, of syndromes, and of the efficacy of treatments. Effective therapies have permitted the extrapolation of humane treatment, so that many fewer patients require institutional care. Because of our desire to find simple, comprehensive and fully effective cures, and because of the tendency of the human mind to engage in wishful thinking, we have gone too far down several dead-end streets. We thought at one time that intensive, frequent, deep psychotherapy (including psychoanalysis) could correct or cure all ills, and we overprescribed that treatment to the detriment of some of our patients. We have learned that therein lies no panacea. We came to believe that hospitals caused more of the problems than they did in fact cause, and that it should be possible to treat all disorders within the community. As a result, we have disassembled some of our excellent institutions, for which there is still some need. At the same time, we have left too unprotected many of those who still require safe asylum, to their great disadvantage and to our public shame.(ABSTRACT TRUNCATED AT 250 WORDS)

Canada↗
PubMedDate not supplied

The most vulnerable among us.

Although many of the more than 17 million refugees and asylum seekers worldwide are injured or hungry, many more of them suffer from psychological harm because of torture, psychological violation, forced displacement, rape, and extended deprivation. As a result, many resettled refugees in the United States are at significantly higher risk of developing mental health problems due to both the trauma from which they fled and the challenge of adjusting to their new lives. Because of its emphasis on the individual, the Western model of psychotherapy may seem foreign to many refugee populations. In many cultures, people disclose deep mental anguish only in the company of a few trusted individuals. Some refugees may also have difficulty confiding in medical professionals because they have learned not to trust authority figures. In order for mental health therapy to be successful with refugees, an appropriate interpreter-one who matches not only the language of the client but also the ethnic and political identity-is crucial.

Health Services Needs and Demand↗