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1.
Cereb Cortex ; 24(9): 2401-8, 2014 Sep.
Article in English | MEDLINE | ID: mdl-23592823

ABSTRACT

A strong relationship between cortical folding and the location of primary sensory areas in the human brain is well established. However, it is unknown if coupling between functional responses and gross anatomy is found at higher stages of sensory processing. We examined the relationship between cortical folding and the location of the retinotopic maps hV4 and VO1, which are intermediate stages in the human ventral visual processing stream. Our data show a consistent arrangement of the eccentricity maps within hV4 and VO1 with respect to anatomy, with the consequence that the hV4/VO1 boundary is found consistently in the posterior transverse collateral sulcus (ptCoS) despite individual variability in map size and cortical folding. Understanding this relationship allowed us to predict the location of visual areas hV4 and VO1 in a separate set of individuals, using only their anatomies, with >85% accuracy. These findings have important implications for understanding the relation between cortical folding and functional maps as well as for defining visual areas from anatomical landmarks alone.


Subject(s)
Cerebral Cortex/anatomy & histology , Cerebral Cortex/physiology , Visual Perception/physiology , Adolescent , Adult , Brain Mapping , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Photic Stimulation , Visual Pathways/anatomy & histology , Visual Pathways/physiology , Young Adult
2.
Cereb Cortex ; 24(4): 883-97, 2014 Apr.
Article in English | MEDLINE | ID: mdl-23211209

ABSTRACT

Neuroimaging studies have identified brain regions that respond preferentially to specific stimulus categories, including 3 areas that activate maximally during viewing of real-world scenes: The parahippocampal place area (PPA), retrosplenial complex (RSC), and transverse occipital sulcus (TOS). Although these findings suggest the existence of regions specialized for scene processing, this interpretation is challenged by recent reports that activity in scene-preferring regions is modulated by properties of isolated single objects. To understand the mechanisms underlying these object-related responses, we collected functional magnetic resonance imaging data while subjects viewed objects rated along 7 dimensions, shown both in isolation and on a scenic background. Consistent with previous reports, we find that scene-preferring regions are sensitive to multiple object properties; however, results of an item analysis suggested just 2 independent factors--visual size and the landmark suitability of the objects--sufficed to explain most of the response. This object-based modulation was found in PPA and RSC irrespective of the presence or absence of a scenic background, but was only observed in TOS for isolated objects. We hypothesize that scene-preferring regions might process both visual qualities unique to scenes and spatial qualities that can appertain to either scenes or objects.


Subject(s)
Brain/physiology , Pattern Recognition, Visual/physiology , Size Perception/physiology , Space Perception/physiology , Adult , Brain/blood supply , Brain Mapping , Female , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Oxygen/blood , Photic Stimulation , Regression Analysis , Young Adult
3.
Behav Pharmacol ; 24(5-6): 504-16, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23839029

ABSTRACT

This double-blind, placebo-controlled study investigated the effects of oral morphine (0, 45, 135 mg/70 kg) and oral oxycodone (0, 15, 45 mg/70 kg) on buprenorphine-maintained opioid addicts. As a 3: 1 morphine : oxycodone oral dose ratio yielded equivalent subjective and physiological effects in nondependent individuals, this ratio was used in the present study. Two self-administration laboratory procedures - that is, a drug versus money and a drug versus drug procedure - were assessed. Study participants (N=12) lived in the hospital and were maintained on 4 mg/day sublingual buprenorphine. When participants chose between drug and money, money was preferred over all drug doses; only high-dose oxycodone was self-administered more than placebo. When participants chose between drug and drug, both drugs were chosen more than placebo, high doses of each drug were chosen over low doses, and high-dose oxycodone was preferred over high-dose morphine. The subjective, performance-impairing, and miotic effects of high-dose oxycodone were generally greater than those of high-dose morphine. The study demonstrated that a 3: 1 oral dose ratio of morphine : oxycodone was not equipotent in buprenorphine-dependent individuals. Both self-administration procedures were effective for assessing the relative reinforcing effects of drugs; preference for one procedure should be driven by the specific research question of interest.


Subject(s)
Analgesics, Opioid/administration & dosage , Morphine/administration & dosage , Opioid-Related Disorders/psychology , Oxycodone/administration & dosage , Reward , Administration, Oral , Adult , Buprenorphine/therapeutic use , Choice Behavior/drug effects , Choice Behavior/physiology , Dose-Response Relationship, Drug , Double-Blind Method , Female , Humans , In Vitro Techniques , Male , Middle Aged , Narcotic Antagonists/therapeutic use , Opioid-Related Disorders/drug therapy , Pain Measurement , Pupil/drug effects , Pupil/physiology , Self Administration , Surveys and Questionnaires , Time Factors , Token Economy , Young Adult
4.
J Neurosci ; 33(13): 5466-74, 2013 Mar 27.
Article in English | MEDLINE | ID: mdl-23536062

ABSTRACT

Intense debate surrounds the role of medial temporal lobe (MTL) structures in recognition memory. Using high-resolution fMRI and analyses of pattern similarity in humans, we examined the encoding computations subserved by MTL subregions. Specifically, we tested the theory that MTL cortex supports memory by encoding overlapping representations, whereas hippocampus supports memory by encoding pattern-separated representations. Consistent with this view, the relationship between encoding pattern similarity and subsequent memory dissociated MTL cortex and hippocampus: later memory was predicted by greater across-item pattern similarity in perirhinal cortex and in parahippocampal cortex, but greater pattern distinctiveness in hippocampus. Additionally, by comparing neural patterns elicited by individual stimuli regardless of subsequent memory, we found that perirhinal cortex and parahippocampal cortex exhibited differential content sensitivity for multiple stimulus categories, whereas hippocampus failed to demonstrate content sensitivity. These data provide novel evidence that complementary MTL encoding computations subserve declarative memory.


Subject(s)
Brain Mapping , Pattern Recognition, Visual/physiology , Recognition, Psychology/physiology , Temporal Lobe/physiology , Adolescent , Adult , Female , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Oxygen/blood , Photic Stimulation , Temporal Lobe/blood supply , Young Adult
5.
Addiction ; 108(2): 385-93, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22882771

ABSTRACT

AIMS: To investigate trends in volatile substance abuse (VSA) deaths over 25 years. DESIGN: A national mortality surveillance programme with standardised data collection procedures. SETTING: The UK and islands. PARTICIPANTS/MEASUREMENTS: All VSA deaths, 1983-2007. FINDINGS: In the five quinquennia from 1983 to 2007 the numbers of VSA deaths were 499, 609, 378, 349 and 258 respectively. There were gradual increases in the mean age at death in males and females and in the number of VSA deaths in women. Coincident with the 1992 Department of Health Advertising Campaign, VSA deaths in boys and girls (<18 years of age) fell by an estimated 56% (95% CI: 36%-70%) and 64% (20%-84%), respectively, from the underlying trend, but there was no evidence of any similar step change in either group following the 1999 Legislation prohibiting sales of cigarette lighter refills containing butane to those under the age of 18 years. Between 1983-1987 and 2003-2007, the ratio of aerosol to gas fuel deaths fell by an estimated 80% (57% to 91%) in adults, while the ratio of glue to gas fuel deaths fell by an estimated 95% (89% to 97%) in adults and an estimated 87% (-1% to 98%) in children. CONCLUSIONS: Between 1983 and 2007, in the United Kingdom, the numbers of deaths associated with volatile substance abuse peaked in the early 1990s and fell to their lowest level in the mid-2000s. The age at death increased in both males and females. There was a fall in the proportion of volatile substance abuse deaths involving glues and a rise, particularly in adults, in the proportion involving gas fuels.


Subject(s)
Inhalant Abuse/mortality , Adhesives/adverse effects , Adolescent , Adult , Aerosols/adverse effects , Age Factors , Algorithms , Butanes/adverse effects , Child , Databases, Factual , Female , Humans , Male , Population Surveillance , Sex Factors , Solvents/adverse effects , United Kingdom/epidemiology , Young Adult
6.
J Speech Lang Hear Res ; 55(1): 45-54, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22199198

ABSTRACT

PURPOSE: In this study, the authors investigated sentence comprehension and spatial working memory abilities in a sample of internationally adopted, postinstitutionalized (PI) children. The authors compared the performance of these PI children with that of an age-matched group of children living with their birth families. They hypothesized that PI children would perform below clinical threshold on tasks of sentence comprehension and that poor sentence comprehension would be associated with poor performance in working memory. METHOD: Twenty-three PI children and 36 comparison children were administered sentence comprehension and spatial memory tasks from standardized assessments. RESULTS: Some oral sentence comprehension skills and the spatial working memory skills were weaker in the school-age PI children than in the age-matched comparison children. A mediational analysis demonstrated that poor spatial working memory performance partially explains the sentence comprehension differences between the 2 groups. CONCLUSION: These findings provide valuable information to better plan early intervention and special education for PI children.


Subject(s)
Child Language , Child, Institutionalized , Comprehension , Critical Period, Psychological , Memory, Short-Term , Spatial Behavior , Adoption , Case-Control Studies , Child , Female , Humans , Language Tests , Male , Matched-Pair Analysis , Maternal Deprivation , Orphanages , Reference Values , Semantics , Social Environment
7.
Ophthalmic Epidemiol ; 16(4): 238-42, 2009.
Article in English | MEDLINE | ID: mdl-19874145

ABSTRACT

PURPOSE: To assess methods used for glaucoma screening in the Student Sight Savers Program (SSSP), an initiative of the Friends of the Congressional Glaucoma Caucus Foundation that has screened individuals for glaucoma in the United States since 2001. METHODS: This was a prospective, case-control, clinic-based study (total N = 70). Patients with primary open-angle glaucoma and age- and sex-matched controls with no evidence of glaucoma or other ocular disease were evaluated with the SSSP screening method. Primary outcome measures were sensitivity, specificity, and positive predictive power for both low- and high-prevalence populations. RESULTS: Sensitivity and specificity values of the individual tests were 48.6% and 68.6% for family history of glaucoma, 22.1% and 78.6% for intraocular pressure (IOP), and 58.1% and 98.6% for frequency doubling technology (FDT) visual field (P = 0.03, chi-square). Specificity of FDT was significantly better than IOP (P < 0.001) and the questionnaire (P < 0.01) by z-test. When analyzing the overall screening criteria (positive screen was >or= 1 positive in the three tests), the sensitivity increased to 88.6% with reduction in specificity to 57.1%. The positive predictive power (PPP) for high-prevalence population was low for the overall screening criteria (15.4%) and highest for FDT as an individual (34.0%) or combined (41.0% to 45.3%) test. The medical student education and community awareness aspects of the program were not assessed. CONCLUSIONS: Of different methods used in the SSSP, FDT was the best single screening test, demonstrating high specificity but only moderate sensitivity. Use of multiple screening criteria resulted in slightly increased sensitivity and PPP over FDT, but decreased specificity.


Subject(s)
Diagnostic Techniques, Ophthalmological , Glaucoma, Open-Angle/diagnosis , Adult , Aged , Aged, 80 and over , Case-Control Studies , False Positive Reactions , Female , Humans , Intraocular Pressure , Male , Middle Aged , Predictive Value of Tests , Prevalence , Prospective Studies , Sensitivity and Specificity , Surveys and Questionnaires , Visual Field Tests , Visual Fields
8.
Ann Emerg Med ; 53(6): 785-91, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19167786

ABSTRACT

STUDY OBJECTIVE: We investigate the test performance of emergency physician-performed sonographic measurement of optic nerve sheath diameter for diagnosis of increased intracranial pressure. METHODS: Children between the ages of 0 and 18 years with suspected increased intracranial pressure were prospectively recruited from the emergency department and ICU of an urban, tertiary-level, freestanding pediatric facility. Pediatric emergency physicians with goal-directed training in ophthalmic sonography measured optic nerve sheath diameter. Images were recorded and subsequently reviewed by a pediatric ophthalmologist and an ophthalmic sonographer, both of whom were blind to the patient's clinical condition. Measurements obtained by the ophthalmic sonographer were considered the criterion standard. An optic nerve sheath diameter greater than 4.0 mm in subjects younger than 1 year and greater than 4.5 mm in older children was considered abnormal. The diagnosis of increased intracranial pressure was based on results of cranial imaging or direct measurement of intracranial pressure. RESULTS: Sixty-four patients were recruited, of whom 24 (37%) had a confirmed diagnosis of increased intracranial pressure. The sensitivity of optic nerve sheath diameter as a screening test for increased intracranial pressure was 83% (95% confidence interval [CI] 0.60 to 0.94); specificity was 38% (95% CI 0.23 to 0.54); positive likelihood ratio was 1.32 (95% CI 0.97 to 1.79) and negative likelihood ratio was 0.46 (95% CI 0.18 to 1.23). There was fair to good interobserver agreement between the pediatric emergency physician and ophthalmic sonographer (kappa 0.52) and pediatric ophthalmologist (kappa 0.64). CONCLUSION: The sensitivity and specificity of bedside sonographic measurement of optic nerve sheath diameter is inadequate to aid medical decisionmaking in children with suspected increased intracranial pressure. Pediatric emergency physicians with focused training by a pediatric ophthalmologist familiar with ophthalmic sonography can measure optic nerve sheath diameter accurately.


Subject(s)
Intracranial Hypertension/diagnostic imaging , Optic Nerve/diagnostic imaging , Optic Nerve/pathology , Point-of-Care Systems , Adolescent , Child , Child, Preschool , Clinical Competence , Emergency Service, Hospital , Female , Humans , Infant , Infant, Newborn , Intensive Care Units, Pediatric , Likelihood Functions , Male , ROC Curve , Ultrasonography
9.
Psychiatr Serv ; 59(6): 648-54, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18511585

ABSTRACT

OBJECTIVE: Illinois public hospitalizations over a ten-year period were studied to determine the impact of recent immigration. The study also explored clinical and demographic differences between immigrant groups and native-born Americans. METHODS: Information was collected from the state hospital Clinical Information System for 1993, 1998, and 2003. Variables included age, sex, race, marital status, education, diagnosis, length of stay, birthplace, citizenship, primary language, English proficiency, and availability of a Social Security number. Logistic multiple regression was used to analyze trends in the proportion of psychiatric admissions of foreign-born patients, with foreign born as the dependent variable and year as the independent variable. Chi square analysis was used for trends across time. RESULTS: In the hospitalized population, the proportion of immigrants was 7.3% in 1993, 10.9% in 1998, and 13.1% in 2003. With covariates adjusted for, the average increase of 8.0% per year in the odds of being foreign born was statistically significant (odds ratio=1.08, 95% confidence interval=1.06-1.10). Nevertheless, the proportion of foreign-born hospital admissions, including Asian and Mexican immigrants, was below their population ratio in Illinois. Mexican-origin immigrants constituted the largest group of admissions and were younger, less educated, had poorer English skills, and were more likely to be undocumented than other immigrants. CONCLUSIONS: The percentage of foreign-born patients admitted was lower than their percentage in the overall population. In previous immigration waves, immigrants were hospitalized at disproportionately higher rates than nonimmigrants. The gap is slowly narrowing as new admissions are increasingly likely to be foreign born, suggesting that public psychiatric hospitals should prepare for these changing populations.


Subject(s)
Emigration and Immigration , Hospitalization/trends , Hospitals, Psychiatric , Adult , Female , Humans , Illinois , Indians, North American , Logistic Models , Male , Medical Records , Middle Aged
10.
Pediatrics ; 117(3): 763-70, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16510656

ABSTRACT

OBJECTIVE: The purpose of this research was to characterize behavioral and cognitive profiles of clinically and immunologically stable antiretroviral-experienced HIV-infected children. METHODS: Two hundred seventy-four previously treated HIV-infected children aged 2 to 17 years were assessed for behavioral, developmental, and cognitive functioning. Correlations between neuropsychological measures, age, and CD4 lymphocyte count were investigated. RESULTS: The most common behavioral problems, as measured by the Conners' Parent Rating Scale, were psychosomatic (28%), learning (25%), hyperactivity (20%), impulsive-hyperactive (19%), conduct (16%), and anxiety (8%) problems. Mean Wechsler Intelligence Scale for Children-III scores were less than established population norms; the mean verbal IQ was 85, the mean performance IQ was 90, and the mean full-scale score was 86. Hyperactivity was more frequent in children with a Wechsler Intelligence Scale for Children-III performance IQ of <90. Anxiety problems were more likely in children > or =9 years of age. Children with CD4 counts of <660 cells per mm3 were more likely to be identified as having a conduct disorder. No association was noted between behavioral problems and neuroimaging. CONCLUSIONS: Clinically and immunologically stable HIV-infected children had more frequent behavioral problems and lower developmental and cognitive scores than established childhood norms.


Subject(s)
Child Behavior Disorders/complications , Cognition , Developmental Disabilities/complications , HIV Infections/complications , Adolescent , Anti-Retroviral Agents , Attention Deficit Disorder with Hyperactivity/complications , Child , Child, Preschool , Female , HIV Infections/drug therapy , HIV Infections/psychology , Humans , Intelligence , Male
11.
J Behav Health Serv Res ; 30(3): 304-20, 2003.
Article in English | MEDLINE | ID: mdl-12875098

ABSTRACT

Despite growing interest in assessment of program implementation, little is known about the best way to evaluate whether a particular program has implemented the intended service to a level that is minimally acceptable to a funding source, such as a state mental health authority. Such is the case for assertive community treatment (ACT), an evidence-based practice being widely disseminated. Using an exploratory, actuarial approach to defining program standards, this study applies different statistical criteria for determining whether or not a program meets ACT standards using the 28-item Dartmouth Assertive Community Treatment Scale. The sample consists of 51 ACT programs, 25 intensive case management programs, and 11 brokered case management programs which were compared to identify levels of fidelity that discriminated between programs, but were still attainable by the majority of ACT programs. A grading system based on mean total score for a reduced set of 21 items appeared to be most attainable, but still discriminated ACT programs from other forms of case management. Implications for setting and evaluating ACT program standards are discussed.


Subject(s)
Case Management/standards , Community Mental Health Services/standards , Program Evaluation/methods , Therapeutic Community , Community Mental Health Services/economics , Community Mental Health Services/legislation & jurisprudence , Evidence-Based Medicine , Financing, Government , Humans , United States
12.
Clin Ther ; 24(11): 1871-86, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12501880

ABSTRACT

BACKGROUND: Alendronate, an oral bisphosphonate, is available for the treatment of osteoporosis in a 70-mg once-weekly and a 10-mg once-daily formulation. OBJECTIVES: This study aimed to determine patient preference for once-weekly versus once-daily dosing with alendronate, and to determine which treatment regimen the patients believed was more convenient and would be easier to comply with for a long period. METHODS: This was a multicenter, randomized, open-label, preference study in which postmenopausal women with osteoporosis were enrolled to receive 9 weeks of treatment in crossover fashion (4 weeks with each study regimen separated by a 1-week washout period). The study regimens included once-weekly alendronate 70 mg and once-daily alendronate 10 mg. The primary and secondary end points were assessed with a questionnaire completed by the patient. Adverse events (AEs) were recorded to assess patient tolerability of the study medications. RESULTS: A total of 324 patients met the eligibility requirements; 288 were randomized to treatment, 287 (mean age, 64.8 years) received treatment, 272 completed the questionnaire, and 266 completed the study. Of the patients who completed the questionnaire, 235 patients preferred the 70-mg once-weekly dosing regimen compared with the 10-mg once-daily regimen (86.4% vs 9.2%; P < 0.001). Most patients also believed that once-weekly dosing was more convenient than once-daily dosing (89.0% vs 7.7%; P < 0.001) and would allow them to achieve better long-term compliance (87.5% vs 8.5%; P < 0.001). Clinical AEs were reported in 30.7% of patients treated with once-weekly alendronate and 30% of patients treated with once-daily alendronate, with no significant differences between treatments. CONCLUSION: When once-weekly alendronate 70 mg was compared with once-daily alendronate 10 mg in this study, 70-mg once-weekly alendronate was the preferred dosing regimen.


Subject(s)
Alendronate/administration & dosage , Osteoporosis, Postmenopausal/drug therapy , Patient Satisfaction , Surveys and Questionnaires , Administration, Oral , Adult , Aged , Alendronate/adverse effects , Alendronate/therapeutic use , Cross-Over Studies , Female , Humans , Middle Aged , Osteoporosis, Postmenopausal/physiopathology , Patient Compliance , United States
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