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1.
Theory Decis ; 96(4): 517-553, 2024.
Article in English | MEDLINE | ID: mdl-38752153

ABSTRACT

We consider a group of receivers who share a common prior on a finite state space and who observe private correlated messages that are contingent on the true state of the world. Our focus lies on the beliefs of receivers induced via the signal chosen by the sender and we provide a comprehensive analysis of the inducible distributions of posterior beliefs. Classifying signals as minimal, individually minimal, and language-independent, we show that any inducible distribution can be induced by a language-independent signal. We investigate the role of the different classes of signals for the amount of higher order information that is revealed to receivers. The least informative signals that induce a fixed distribution over posterior belief profiles lie in the relative interior of the set of all language-independent signals inducing that distribution.

2.
Brain Struct Funct ; 221(1): 147-58, 2016 Jan.
Article in English | MEDLINE | ID: mdl-25269832

ABSTRACT

Previous literature has shown that hypoglycemia influences the intensity of the BOLD signal. A similar but smaller effect may also be elicited by low normal blood glucose levels in healthy individuals. This may not only confound the BOLD signal measured in fMRI, but also more generally interact with cognitive processing, and thus indirectly influence fMRI results. Here we show in a placebo-controlled, crossover, double-blind study on 40 healthy subjects, that overnight fasting and low normal levels of glucose contrasted to an activated, elevated glucose condition have an impact on brain activation during basal visual stimulation. Additionally, functional connectivity of the visual cortex shows a strengthened association with higher-order attention-related brain areas in an elevated blood glucose condition compared to the fasting condition. In a fasting state visual brain areas show stronger coupling to the inferior temporal gyrus. Results demonstrate that prolonged overnight fasting leads to a diminished BOLD signal in higher-order occipital processing areas when compared to an elevated blood glucose condition. Additionally, functional connectivity patterns underscore the modulatory influence of fasting on visual brain networks. Patterns of brain activation and functional connectivity associated with a broad range of attentional processes are affected by maturation and aging and associated with psychiatric disease and intoxication. Thus, we conclude that prolonged fasting may decrease fMRI design sensitivity in any task involving attentional processes when fasting status or blood glucose is not controlled.


Subject(s)
Brain/physiology , Fasting , Photic Stimulation , Visual Perception/physiology , Adult , Blood Glucose/analysis , Cross-Over Studies , Double-Blind Method , Epinephrine/blood , Fasting/blood , Female , Humans , Hydrocortisone/blood , Insulin/blood , Male , Norepinephrine/blood , Temporal Lobe/physiology , Visual Cortex/physiology , Young Adult
3.
Neuroimage ; 113: 246-56, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25795339

ABSTRACT

Glucose is the primary source of energy for the human brain. Previous literature has shown that varying blood glucose levels may have a strong impact on behaviour, subjective mood, and the intensity of the BOLD signal measured in fMRI. Therefore, blood glucose levels varying even within the normal range may interact with cognitive and emotional processing as well as BOLD signal. Here, in a placebo-controlled, double-blind crossover study on 20 healthy women, we show that overnight fasting, compared to an elevated glucose condition, influences brain activation and the affective state during mood induction. Results indicate that our brain may compensate for low glucose levels during fasting by stronger recruitment of the brain areas relevant to the task at hand. Additionally, we systematically tested the effect of prior cognitive effort on behavioural and neural patterns and found that elevated activation is only associated with maintained performance as long as no prior cognitively challenging task is administered. Prior cognitive effort leads to deteriorated performance and a further increase in emotion-associated brain activation in the pregenual anterior and posterior cingulate, the superior frontal gyrus, and the pre-SMA. These results are in line with the strength model of self-regulation. Our results corroborate the strength model of self-regulation and extend it to affect regulation processes. Additionally, our observations suggest that experimentally controlling for fasting state or glucose levels may be beneficial, especially when studying processes that involve self-regulation.


Subject(s)
Affect/drug effects , Blood Glucose/metabolism , Adult , Cross-Over Studies , Double-Blind Method , Facial Expression , Fasting/psychology , Female , Gyrus Cinguli/physiology , Happiness , Humans , Magnetic Resonance Imaging , Neural Pathways/physiology , Recruitment, Neurophysiological , Self-Control , Young Adult
4.
Am J Orthod Dentofacial Orthop ; 134(1): 85-92, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18617107

ABSTRACT

INTRODUCTION: The aims of this study were to evaluate 3-dimensional (3D) tooth crown sizes in patients with cleft lip and palate (CLP) and to compare them with those of a Class I control group. METHODS: Orthodontic dental casts were used of 72 subjects with CLP (20 bilateral [BCLP], 34 unilateral left [ULCLP], 18 unilateral right [URCLP]) and 53 adolescents in the permanent dentition stage with Class I occlusion. Mesiodistal (MD), labiolingual (LL), and occlusogingival (OG) measurements were recorded by the same examiner using a digital caliper. Statistical analyses were conducted, including repeatability, analysis of variance (ANOVA), and the Duncan tests. RESULTS: Maxillary and mandibular premolar MD dimensions were larger in the CLP groups than in the control group. The smallest MD dimensions were those of the maxillary right lateral incisors in the BCLP group (P <0.05). The maxillary left lateral incisor MD dimensions in the ULCLP group were smaller when compared with other CLP groups (P <0.001). In general, all LL and OG measurements were smaller in the CLP groups than in the Class I group in both dental arches. CONCLUSIONS: In general, MD, LL, and OG dimensions of CLP patients were smaller than those of the Class I subjects, not only in the affected maxillary dental arch, but also in the mandibular dental arch. Variations in 3D tooth dimensions were found among all CLP types. The lateral incisor in the cleft region was the smallest. A 3D tooth-size evaluation should be included in the diagnostic records to determine precise treatment planning and final occlusion in CLP patients.


Subject(s)
Cleft Lip/pathology , Cleft Palate/pathology , Imaging, Three-Dimensional/methods , Odontometry/methods , Tooth Crown/pathology , Adolescent , Bicuspid/pathology , Cuspid/pathology , Dental Arch , Dental Occlusion , Female , Humans , Incisor/pathology , Male , Mandible , Maxilla , Models, Dental , Molar/pathology
5.
Eur J Orthod ; 28(4): 383-92, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16731542

ABSTRACT

The aim of this study was to examine the dentofacial changes in Class III patients treated with fixed appliances subsequent to rapid maxillary expansion (RME) and facemask therapy. The material consisted of the cephalograms and hand-wrist films of 14 (9 girls, 5 boys) skeletal Class III and 15 (10 girls, 5 boys) untreated subjects obtained at the beginning of treatment/observation T1, immediately after orthopaedic therapy T2, and at the end of the observation period T3. The mean pre-treatment/control ages were approximately 11.5 years and the observation period was 3 years T2-T1: 1 year, T3-T2: 2 years). The cephalometric films were analysed according to the structural superimposition method of Björk. All tracings were double-digitized and the measurements were calculated by a computer program. Intragroup changes and intergroup differences were statistically analysed. Forward movement of the maxilla (P < 0.01), backward movement and rotation of the mandible, an increase in the ANB angle (P < 0.001), lower face height and overjet (P < 0.001), a decrease of overbite, and an improvement in the sagittal lip relationship (P < 0.01) presented significant intergroup differences between T2 and T1. During the second phase of treatment T3-T2, although not statistically significant, forward movement of the maxilla was less than in the control subjects. Overall changes during the observation period T3-T1 revealed that correction was mainly due to favourable changes in the mandibular and dentoalveolar components of the discrepancy, while these in maxillary position were not different from the control group. The soft tissue profile improved significantly (P < 0.001) in the treatment group. Comparison with the Class I controls at the end of the observation period confirmed that some Class III characteristics still remained in the treated patients.


Subject(s)
Activator Appliances , Face/anatomy & histology , Malocclusion, Angle Class III/therapy , Palatal Expansion Technique/instrumentation , Cephalometry , Child , Facies , Female , Humans , Longitudinal Studies , Male , Treatment Outcome
6.
Cleft Palate Craniofac J ; 41(5): 485-89, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15352869

ABSTRACT

OBJECTIVE: The aim of this study was to evaluate cephalometrically the lower lip position and area of patients with unilateral cleft lip and palate (UCLP) comparatively with Class I skeletodental normal subjects. PATIENTS: Lateral cephalometric and hand-wrist radiographs obtained from 24 patients with UCLP (mean age 12.86 years), along with 20 normal individuals (mean age 12.33 years) used as a control group, were examined. DESIGN: In addition to standard cephalometric dentofacial variables, lower lip area (superior, middle, inferior) was also measured using a digital planimeter on the lateral cephalograms. RESULTS: The superior and middle part of the lower lip areas were significantly smaller (p < .05) in the UCLP group, compared to the control group. The inferior and total lower lip areas of patients with UCLP were found to be significantly smaller than controls. The labiomental angle was also smaller (38.79 degrees). CONCLUSIONS: The results suggest that the lower lip of patients with UCLP is smaller, retruded, and curved, with a deep labiomental sulcus, compared with normal individuals during puberty. Therefore, practitioners should focus not only on the upper lip of patients with UCLP but also should consider the lower lip as it was found distinct from normal individuals during puberty.


Subject(s)
Cleft Lip/pathology , Cleft Palate/pathology , Lip/pathology , Case-Control Studies , Cephalometry , Child , Female , Humans , Male , Maxillofacial Development
7.
Angle Orthod ; 74(6): 733-40, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15673133

ABSTRACT

The aim of this study was to evaluate and compare the soft tissue effects of chincup (CC), chincup plus bite plate (CC+P), and reverse headgear (RHg) therapies with each other and with an untreated control group (C). The material consisted of lateral cephalometric and hand-wrist films of 59 Class III cases and 20 nontreated control subjects. Thirty-one cases were treated with CC, 14 with CC+P, and 14 with RHg, and Class I relation was achieved. The mean pretreatment ages were approximately 11 years and the observation period was one year. The cephalometric films were analyzed according to the structural superimposition method of Björk. All tracings were double digitized, and the measurements were calculated by a computer program (PORDIOS). Treatment and control changes within the groups and the differences between the groups were analyzed statistically. Forward positioning of the maxilla was significant in the RHg group, whereas the mandible was positioned backward significantly in all the treatment groups. Posterior rotation of the mandible was significant in the CC+P and RHg groups. The overjet increased and the overbite decreased significantly in all the treatment groups. Forward movement of soft tissue A and upper lip was significant in all groups, whereas more pronounced in the CC+P group. The soft tissue changes in the mandibular region were significant in the CC and CC+P groups, whereas in the maxillary region more significant and similar improvements were obtained by CC+P and RHg treatments. Longterm studies are required to confirm the stability of these changes.


Subject(s)
Cephalometry , Extraoral Traction Appliances/classification , Face , Malocclusion, Angle Class III/therapy , Orthodontic Appliance Design , Activator Appliances , Adolescent , Age Determination by Skeleton , Child , Female , Follow-Up Studies , Humans , Image Processing, Computer-Assisted , Incisor/pathology , Lip/pathology , Male , Malocclusion, Angle Class III/pathology , Mandible/pathology , Maxilla/pathology , Palatal Expansion Technique/instrumentation , Prognathism/pathology , Prognathism/therapy , Retrospective Studies , Vertical Dimension
8.
Am J Orthod Dentofacial Orthop ; 122(5): 512-22, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12439480

ABSTRACT

The aim of this study was to evaluate longitudinally the natural craniofacial and dentoalveolar changes that occur in the third decade of life. Natural head position lateral cephalometric films and dental casts of 30 people (14 women and 16 men) were evaluated. The mean age at the beginning of the observation period was 22.35 years for the women and 22.19 years for the men, and the observation period was approximately 10 years. Cephalometric films were superimposed by the structural method, and the measurements of the dental casts were made with a digital caliper. All tracings were digitized, and changes in the 65 cephalometric and 10 dental cast measurements were evaluated statistically. In this early adult period, small changes were found in the craniofacial and craniocervical parameters; the changes were more significant in the women. The most significant changes were found in the vertical dimension. The total anterior face height increased in both genders, while the lower anterior face height increased significantly in the female group. Soft tissue measurements reflected the vertical skeletal changes. The retrusion of the upper lip was significant in the women, and the upper lip thickness decreased in both genders. In the dentoalveolar region, the main movement was eruption of the teeth. The overbite amount increased significantly only in the female group. All dental arch measurements decreased in both sexes. The decrease in the mandibular arch length discrepancy was significant in the men. These findings have important clinical implications regarding the long-term stability and retention of orthodontic and orthognathic surgery treatment results.


Subject(s)
Aging/pathology , Face/anatomy & histology , Facial Bones/anatomy & histology , Skull/anatomy & histology , Adult , Alveolar Process/anatomy & histology , Cephalometry , Dental Arch/anatomy & histology , Dental Occlusion , Female , Follow-Up Studies , Humans , Image Processing, Computer-Assisted , Lip/anatomy & histology , Longitudinal Studies , Male , Mandible/anatomy & histology , Matched-Pair Analysis , Models, Dental , Neck/anatomy & histology , Reproducibility of Results , Sex Factors , Statistics as Topic , Tooth/anatomy & histology , Tooth Eruption/physiology , Vertical Dimension
9.
Angle Orthod ; 72(6): 521-6, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12518943

ABSTRACT

The relationship between the soft palate and the nasopharyngeal airway in different mandibular growth rotation models was investigated. A total of 72 lateral cephalograms were obtained three years longitudinally from 24 individuals. The subjects had a mean age of 10.7 +/- 1.2 years and showed a normal (n = 8), posterior (n = 8), and anterior (n = 8) mandibular rotation pattern. Linear and angular measurements of the soft palate and nasopharyngeal airway were recorded by using PORDIOS computer program and were examined by means of descriptive statistics and paired t-tests. A linear increase in the soft palate length (SPL) was observed in all groups, with the posterior mandibular rotation group showing the largest increase within the observation period (28.56 +/- 4.83 to 34.98 +/- 2.87; P < .01). According to the paired t-test, palatal plane (ANS-PNS)/soft palate tip (SPT) angle showed a statistically significant decrease in the posterior rotation group (P < .01). The ratio between SPL and superior nasopharyngeal space (SPS) did not show a statistically significant difference among the groups. Although various amounts of soft palate and nasopharyngeal airway growth occurred in the different mandibular rotation types, the ratio between SPL and SPS (SPL/SPS), which plays an indispensable role in velopharyngeal functions, did not show a statistically significant difference in the groups. This assured velopharyngeal closure throughout the active growth period.


Subject(s)
Mandible/growth & development , Nasopharynx/growth & development , Palate, Soft/growth & development , Velopharyngeal Insufficiency/diagnostic imaging , Cephalometry , Child , Female , Humans , Longitudinal Studies , Male , Mandible/diagnostic imaging , Mandible/physiopathology , Nasopharynx/anatomy & histology , Nasopharynx/diagnostic imaging , Palate, Soft/anatomy & histology , Palate, Soft/diagnostic imaging , Radiographic Image Enhancement , Reference Values
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