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1.
NPJ Sci Learn ; 9(1): 22, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499583

RESUMO

Curiosity can be a powerful motivator to learn and retain new information. Evidence shows that high states of curiosity elicited by a specific source (i.e., a trivia question) can promote memory for incidental stimuli (non-target) presented close in time. The spreading effect of curiosity states on memory for other information has potential for educational applications. Specifically, it could provide techniques to improve learning for information that did not spark a sense of curiosity on its own. Here, we investigated how high states of curiosity induced through trivia questions affect memory performance for unrelated scholastic facts (e.g., scientific, English, or historical facts) presented in close temporal proximity to the trivia question. Across three task versions, participants viewed trivia questions closely followed in time by a scholastic fact unrelated to the trivia question, either just prior to or immediately following the answer to the trivia question. Participants then completed a surprise multiple-choice memory test (akin to a pop quiz) for the scholastic material. In all three task versions, memory performance was poorer for scholastic facts presented after trivia questions that had elicited high versus low levels of curiosity. These results contradict previous findings showing curiosity-enhanced memory for incidentally presented visual stimuli and suggest that target information that generates a high-curiosity state interferes with encoding complex and unrelated scholastic facts presented close in time.

2.
J Cogn Neurosci ; 36(5): 888-900, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38307129

RESUMO

Successful learning depends on various factors such as depth of processing, motivation, or curiosity about information. A strong drive to learn something or the expectation of receiving a reward can be crucial to enhance learning. However, the influence of curiosity on the processing of new information and its similarity with reward processing is not well understood. This study examined whether states of curiosity influence specific ERPs associated with reward processing and whether these ERPs are related with later memory benefits. In an initial screening phase, participants indicated their curiosity and confidence in prior knowledge about answers to various trivia questions. In a subsequent study phase, we targeted different time windows related to reward processing during the presentation of trivia answers containing the reward positivity (RewP; 250-350 msec), the P3 (250-500 msec), and the late-positive-potential (LPP; 600-1000 msec). In a following surprise memory test, we found that participants recalled more high- than low-curiosity answers. The RewP, P3, and LPP showed greater positive mean amplitudes for high compared with low curiosity, reflecting increased reward processing. In addition, we found that the RewP and the P3 showed more positive mean amplitudes for later recalled compared with later forgotten answers, but curiosity did not modulate this encoding-related results. These findings support the view that the satisfaction of curiosity resembles reward processing, indicated by ERPs.


Assuntos
Potenciais Evocados , Comportamento Exploratório , Humanos , Motivação , Aprendizagem , Recompensa , Eletroencefalografia
3.
Soc Cogn Affect Neurosci ; 18(1)2023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35975900

RESUMO

Curiosity reflects an individual's intrinsic motivation to seek information in order to close information gaps. In laboratory-based experiments, both curiosity and information seeking have been associated with enhanced neural dynamics in the mesolimbic dopaminergic circuit. However, it is unclear whether curiosity and dopaminergic dynamics drive information seeking in real life. We investigated (i) whether curiosity predicts different characteristics of real-life information seeking and (ii) whether functional connectivity within the mesolimbic dopaminergic circuit is associated with information seeking outside the laboratory. Up to 15 months before the COVID-19 pandemic, curiosity and anxiety questionnaires and a 10-minute resting-state functional magnetic resonance imaging session were conducted. In a follow-up survey early during the COVID-19 pandemic, participants repeated the questionnaires and completed an additional questionnaire about their COVID-19-related information seeking. Individual differences in curiosity but not anxiety were positively associated with the frequency of information-seeking behaviour. Additionally, the frequency of information seeking was predicted by individual differences in resting-state functional connectivity between the ventral tegmental area and the nucleus accumbens. The present translational study paves the way for future studies on the role of curiosity in real-life information seeking by showing that both curiosity and the mesolimbic dopaminergic functional network support real-life information-seeking behaviour.


Assuntos
COVID-19 , Comportamento Exploratório , Humanos , Comportamento de Busca de Informação , Pandemias , Núcleo Accumbens , Área Tegmentar Ventral
4.
Front Endocrinol (Lausanne) ; 13: 967995, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36237184

RESUMO

Pheochromocytomas (PCCs) are rare but potentially lethal tumors that arise from the adrenal medulla. The clinical suspicion and diagnosis of PCC can be challenging due to the non-specific nature of signs and symptoms. In many patients, infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) could lead to long-term symptoms including fatigue, headaches, and cognitive dysfunction. Here, we present the case of a patient incidentally diagnosed with an adrenal mass that proved to be a PCC after imaging was performed due to persisting complaints after coronavirus disease 2019 (COVID-19) infection. A 37-year-old male patient was referred to our center because of a right-sided inhomogeneous adrenal mass, incidentally found during a computed tomographic scan of the thorax performed due to cough and dyspnea that persisted after COVID-19 infection. Other complaints that were present prior to COVID-19 infection included profuse sweating, dizziness, exhaustion with chronic fatigue, and concentration difficulties. The patient had no history of hypertension, his blood pressure was normal, and the 24-h ambulatory blood pressure monitoring confirmed normotension but with the absence of nocturnal dipping. Plasma normetanephrine was 5.7-fold above the upper limit (UL) of reference intervals (738 pg/ml, UL = 129 pg/ml), whereas plasma metanephrine and methoxytyramine were normal at 30 pg/ml (UL = 84 pg/ml) and <4 pg/ml (UL = 16 pg/ml), respectively. Preoperative preparation with phenoxybenzamine was initiated, and a 4-cm tumor was surgically resected. Profuse sweating as well as dizziness was resolved after adrenalectomy pointing toward PCC and not COVID-19-associated patient concerns. Altogether, this case illustrates the difficulties in recognizing the possibility of PCC due to the non-specific nature of signs and symptoms of the tumor, which in this case did not include hypertension and coincided with some of the symptoms of long COVID-19.


Assuntos
Neoplasias das Glândulas Suprarrenais , COVID-19 , Hipertensão , Feocromocitoma , Neoplasias das Glândulas Suprarrenais/complicações , Neoplasias das Glândulas Suprarrenais/diagnóstico , Neoplasias das Glândulas Suprarrenais/cirurgia , Adulto , Monitorização Ambulatorial da Pressão Arterial , COVID-19/complicações , Tontura/complicações , Humanos , Hipertensão/complicações , Masculino , Metanefrina , Normetanefrina , Fenoxibenzamina , Feocromocitoma/complicações , Feocromocitoma/diagnóstico , Feocromocitoma/cirurgia , SARS-CoV-2 , Síndrome Pós-COVID-19 Aguda
5.
Curr Opin Behav Sci ; 39: 178-184, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34435085

RESUMO

Accumulating evidence in adults has shown that curiosity and surprise enhance memory via activity in the hippocampus, prefrontal cortex, and dopaminergic areas. Based on findings of how these brain areas and their inter-connections develop during childhood and adolescence, we discuss how the effects of curiosity and surprise on memory may develop during childhood and adolescence. We predict that the maturation of brain areas potentially related to curiosity elicitation (hippocampus, anterior cingulate cortex [ACC], prefrontal cortex) and protracted development of hippocampal-PFC and ACC-PFC connectivity lead to differential effects of curiosity and surprise on memory during childhood and adolescence. Our predictions are centred within the PACE (Prediction-Appraisal-Curiosity-Exploration) Framework which proposes multiple levels of analyses of how curiosity is elicited and enhances memory.

6.
Learn Mem ; 28(8): 254-259, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34266990

RESUMO

Novelty is a potent driver of learning, but little is known about whether anticipation of novelty can enhance memory for incidental information. Here, participants incidentally encountered objects while they actively navigated toward novel or previously familiarized virtual rooms. Across immediate and delayed surprise memory tests, participants showed superior recollection for incidental objects encountered while anticipating novel as compared with familiarized rooms. Furthermore, memory for incidental objects correlated positively with between-participants average curiosity about novel rooms but negatively with within-participants trial-specific curiosity. Our findings contribute to the growing literature on how salient processes impact memory for incidental material.


Assuntos
Memória , Rememoração Mental , Comportamento Exploratório , Humanos , Aprendizagem
7.
Learn Mem ; 28(2): 34-39, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33452112

RESUMO

Curiosity states benefit memory for target information, but also incidental information presented during curiosity states. However, it is not known whether incidental curiosity-enhanced memory depends on when incidental information during curiosity states is encountered. Here, participants incidentally encoded unrelated face images at different time points while they anticipated answers to trivia questions. Across two experiments, we found memory enhancements for unrelated faces presented during high-curiosity compared with low-curiosity states, but only when presented shortly after a trivia question. This suggests processes associated with the elicitation of curiosity-but not sustained anticipation or the satisfaction of curiosity-enhance memory for incidental information.


Assuntos
Antecipação Psicológica/fisiologia , Comportamento Exploratório/fisiologia , Rememoração Mental/fisiologia , Reconhecimento Psicológico/fisiologia , Adulto , Reconhecimento Facial/fisiologia , Feminino , Humanos , Masculino , Adulto Jovem
8.
Dev Sci ; 24(1): e13005, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32524703

RESUMO

Curiosity - broadly defined as the desire to acquire new information - enhances learning and memory in adults. In addition, interest in the information (i.e., when the information is processed) can also facilitate later memory. To date, it is not known how states of pre-information curiosity and post-information interest enhance memory in childhood and adolescence. We used a trivia paradigm in which children and adolescents (N = 60, 10-14 years) encoded trivia questions and answers associated with high or low curiosity. States of high pre-answer curiosity enhanced later memory for trivia answers in both children and adolescents. However, higher positive post-answer interest enhanced memory for trivia answers beyond the effects of curiosity more strongly in adolescents than in children. These results suggest that curiosity and interest have positive effects on learning and memory in childhood and adolescence, but might need to be harnessed in differential ways across child development to optimize learning.


Assuntos
Comportamento Exploratório , Memória , Adolescente , Adulto , Criança , Humanos , Aprendizagem
9.
AACE Clin Case Rep ; 6(5): e212-e216, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32984523

RESUMO

OBJECTIVE: Both clinical suspicion and diagnosis of pheochromocytoma (PCC) can be challenging in patients where the presentation can be confused with the pharmacophysiological effects of illicit drugs known to activate the sympathetic nervous system. We report on such a patient and outline considerations that can impact diagnostic decision making. METHODS: Clinical examination, measurement of plasma metanephrines, followed by magnetic resonance imaging, iodine 123-metaiodobenzylguanidine single-photon emission computed tomography, and histopathology of the resected tumor. RESULTS: A 35-year-old male patient was referred to our center because of a right-sided adrenal mass, incidentally found during an abdominal ultrasound performed due to nausea, vomiting, and lumbar pain. Although he had no history of hypertension, he had complained for over 6 years of severe episodic headache, panic attacks, and profuse sweating. He also had a longer history of methamphetamine abuse. Plasma concentrations of metanephrine (10.7 pmol/L) and normetanephrine (3.83 pmol/L) were 25-fold and 5.6-fold above respective upper limits of reference intervals (0.42 and 0.69 pmol/L). This indicated a PCC, which was confirmed after adrenalectomy. Failure to recognize the patient's signs and symptoms as attributable to a PCC was unsurprising given that methamphetamine abuse can result in many of the same signs and symptoms as a catecholamine-producing tumor. CONCLUSION: The abuse of drugs such as methamphetamine can obscure an underlying PCC due to the similarity of several symptoms associated with both conditions. Recognition of a PCC in patients using illicit drugs such as methamphetamine remains challenging.

10.
Clin Chim Acta ; 507: 98-103, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32315615

RESUMO

BACKGROUND: Diagnosis of primary aldosteronism (PA) involves a multistep process reliant on the accuracy of aldosterone measurements at each step. We report on immunoassay interference leading to a wrongful diagnosis and indication for surgical intervention. CASE: A 38-year old hypertensive male with a 1.4 cm left adrenal mass was diagnosed with PA based on an elevated aldosterone:renin ratio and a positive saline infusion test. Adrenal venous sampling (AVS) indicated left-sided aldosterone hypersecretion, supporting a decision to remove the left adrenal. The patient was also enrolled in a study to evaluate mass spectrometry-based steroid profiling, which indicated plasma aldosterone concentrations measured in five different peripheral samples averaging only 11% those of the immunoassay. Mass spectrometric measurements did not support left-sided adrenal aldosterone hypersecretion. Two independent laboratories confirmed differences in measurements by immunoassay and mass spectrometry. Lowered concentrations measured by the immunoassay that matched those by mass spectrometry were achieved after sample purification to remove macromolecules, confirming immunoassay interference. CONCLUSIONS: Although our patient may represent an isolated case of immunoassay interference leading to misdiagnosis of PA, unnecessary AVS and potentially wrongful removal of an adrenal, it is also possible that such inaccuracies may impact the diagnostic process and treatment for other patients.


Assuntos
Adrenalectomia , Artefatos , Erros de Diagnóstico , Hiperaldosteronismo/sangue , Hiperaldosteronismo/diagnóstico , Imunoensaio , Espectrometria de Massas , Adulto , Aldosterona/sangue , Humanos , Hiperaldosteronismo/cirurgia , Masculino
11.
Trends Cogn Sci ; 23(12): 1014-1025, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31706791

RESUMO

Curiosity plays a fundamental role for learning and memory, but the neural mechanisms that stimulate curiosity and its effect on memory are poorly understood. Accumulating evidence suggests that curiosity states are related to modulations in activity in the dopaminergic circuit and that these modulations impact memory encoding and consolidation for both targets of curiosity and incidental information encountered during curiosity states. To account for this evidence, we propose the Prediction, Appraisal, Curiosity, and Exploration (PACE) framework, which attempts to explain curiosity and memory in terms of cognitive processes, neural circuits, behavior, and subjective experience. The PACE framework generates testable predictions that can stimulate future investigation of the mechanisms underlying curiosity-related memory enhancements.


Assuntos
Comportamento Exploratório/fisiologia , Hipocampo/fisiologia , Memória/fisiologia , Modelos Neurológicos , Modelos Psicológicos , Animais , Humanos
12.
J Clin Endocrinol Metab ; 104(10): 4331-4340, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30977834

RESUMO

CONTEXT: Diagnosis of subclinical adrenal hypercortisolism is based on several tests of the hypothalamic-pituitary-adrenal axis to establish mild alterations of cortisol secretion and dysregulated cortisol physiology. OBJECTIVE: We assessed whether plasma steroid profiles might assist diagnosis of subclinical Cushing syndrome (SC). DESIGN: Retrospective cross-sectional study. SETTING: Two tertiary medical centers. PATIENTS: Of 208 patients tested for hypercortisolism, disease was excluded in 152 and confirmed in 21 with overt adrenal Cushing syndrome (AC) compared to 35 with SC. Another 277 age- and sex-matched hypertensive and normotensive volunteers were included for reference. MAIN OUTCOME MEASURES: A panel of 15 plasma steroids was measured by mass spectrometry, with classification by discriminant analysis. RESULTS: Patients with SC had lower plasma concentrations of dehydroepiandrosterone and dehydroepiandrosterone-sulfate than subjects without SC (P < 0.05). The largest increases (P < 0.001) in plasma steroids among patients with SC were observed for 11-deoxycortisol and 11-deoxycorticosterone. Nevertheless, concentrations of 11-deoxycorticosterone, 11-deoxycortisol, and pregnenolone in patients with AC were higher (P < 0.05) than in those with SC. Patients with SC or AC could be distinguished from subjects without disease using this combination of steroids as precisely as with use of measurements of serum cortisol after administration of dexamethasone. The steroid combination provided superior diagnostic performance compared with each of the other routine biochemical tests. CONCLUSION: Distinct plasma steroid profiles in patients with SC may provide a simple and reliable screening method for establishing the diagnosis.


Assuntos
Hormônio Adrenocorticotrópico/sangue , Síndrome de Cushing/sangue , Síndrome de Cushing/diagnóstico , Sistema Hipotálamo-Hipofisário/fisiopatologia , Esteroides/sangue , Cromatografia Líquida/métodos , Estudos Transversais , Feminino , Alemanha , Hospitais Universitários , Humanos , Masculino , Análise Multivariada , Curva ROC , Valores de Referência , Estudos Retrospectivos , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Suíça , Espectrometria de Massas em Tandem/métodos
13.
Exp Clin Endocrinol Diabetes ; 127(2-03): 165-175, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30562824

RESUMO

Addison's disease - the traditional term for primary adrenal insufficiency (PAI) - is defined as the clinical manifestation of chronic glucocorticoid- and/or mineralocorticoid deficiency due to failure of the adrenal cortex which may result in an adrenal crisis with potentially life-threatening consequences. Even though efficient and safe pharmaceutical preparations for the substitution of endogenous gluco- and mineralocorticoids are established in therapy, the mortality in patients with PAI is still increased and the health-related quality of life (HRQoL) is often reduced.PAI is a rare disease but recent data report an increasing prevalence. In addition to the common "classical" causes of PAI like autoimmune, infectious, neoplastic and genetic disorders, other iatrogenic conditions - mostly pharmacological side effects (e. g., adrenal haemorrhage associated with anticoagulants, drugs affecting glucocorticoid synthesis, action or metabolism and some of the novel anti-cancer checkpoint inhibitors) are contributing factors to this phenomenon.Due to the rarity of the disease and often non-specific symptoms at least in the early stages, PAI is frequently not considered resulting in a delayed diagnosis. Successful therapy is mainly based on adequate patient education as a cornerstone in the prevention and management of adrenal crisis. A focus of current research is in the development of pharmacokinetically optimized glucocorticoid preparations as well as regenerative therapies.


Assuntos
Doença de Addison/diagnóstico , Doença de Addison/tratamento farmacológico , Doença de Addison/etiologia , Doença de Addison/epidemiologia , Humanos
14.
Cogn Neurosci ; 9(3-4): 100-115, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30124373

RESUMO

Sleep-dependent memory processing is dependent on several factors at learning, including emotion, encoding strength, and knowledge of future relevance. Recent work documents the role of curiosity on learning, showing that memory associated with high-curiosity encoding states is retained better and that this effect may be driven by activity within the dopaminergic circuit. Here, we examined whether this curiosity effect was enhanced by or dependent on sleep-related consolidation. Participants learned the answers to trivia questions that they had previously rated on a curiosity scale, and they were shown faces between each question and answer presentation. Memory for these answers and faces was tested either immediately or after a 12-hour delay containing sleep or wakefulness, and polysomnography data was collected for a subset of the sleep participants. Although the curiosity effect for both the answers and incidentally-learned faces was replicated in immediate tests and after the 12-hour delay, the effect was not impacted by the presence of sleep in either case, nor did the effect show a relationship with total sleep time or time in slow-wave sleep. This study suggests that curiosity may be a learning factor that is not subsequently affected by sleep-dependent memory consolidation, but more work ought to examine the role of sleep on curiosity-driven memory in other contexts.


Assuntos
Comportamento Exploratório/fisiologia , Aprendizagem/fisiologia , Consolidação da Memória/fisiologia , Sono/fisiologia , Adolescente , Adulto , Reconhecimento Facial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polissonografia , Fatores de Tempo , Adulto Jovem
15.
J Cogn Neurosci ; 30(11): 1646-1656, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29952700

RESUMO

Events that violate predictions are thought to not only modulate activity within the hippocampus and PFC but also enhance communication between the two regions. Scalp and intracranial EEG studies have shown that oscillations in the theta frequency band are enhanced during processing of contextually unexpected information. Some theories suggest that the hippocampus and PFC interact during processing of unexpected events, and it is possible that theta oscillations may mediate these interactions. Here, we had the rare opportunity to conduct simultaneous electrophysiological recordings from the human hippocampus and PFC from two patients undergoing presurgical evaluation for pharmacoresistant epilepsy. Recordings were conducted during a task that involved encoding of contextually expected and unexpected visual stimuli. Across both patients, hippocampal-prefrontal theta phase synchronization was significantly higher during encoding of contextually unexpected study items, relative to contextually expected study items. Furthermore, the hippocampal-prefrontal theta phase synchronization was larger for contextually unexpected items that were later remembered compared with later forgotten items. Moreover, we did not find increased theta synchronization between the PFC and rhinal cortex, suggesting that the observed effects were specific to prefrontal-hippocampal interactions. Our findings are consistent with the idea that theta oscillations orchestrate communication between the hippocampus and PFC in support of enhanced encoding of contextually deviant information.


Assuntos
Sincronização Cortical/fisiologia , Hipocampo/fisiologia , Motivação/fisiologia , Estimulação Luminosa/métodos , Córtex Pré-Frontal/fisiologia , Ritmo Teta/fisiologia , Eletrodos Implantados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Exp Aging Res ; 44(4): 311-328, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29787342

RESUMO

Background/study context: Recent studies have shown that young adults better remember factual information they are curious about. It is not entirely clear, however, whether this effect is retained during aging. Here, the authors investigated curiosity-driven memory benefits in young and elderly individuals. METHODS: In two experiments, young (age range 18-26) and older (age range 65-89) adults read trivia questions and rated their curiosity to find out the answer. They also attended to task-irrelevant faces presented between the trivia question and the answer. The authors then administered a surprise memory test to assess recall accuracy for trivia answers and recognition memory performance for the incidentally learned faces. RESULTS: In both young and elderly adults, recall performance was higher for answers to questions that elicited high levels of curiosity. In Experiment 1, the authors also found that faces presented in temporal proximity to curiosity-eliciting trivia questions were better recognized, indicating that the beneficial effects of curiosity extended to the encoding of task-irrelevant material. CONCLUSIONS: These findings show that elderly individuals benefit from the memory-enhancing effects of curiosity. This may lead to the implementation of learning strategies that target and stimulate curiosity in aging.


Assuntos
Envelhecimento/psicologia , Comportamento Exploratório/fisiologia , Aprendizagem/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cognição , Depressão/psicologia , Feminino , Humanos , Masculino , Memória , Rememoração Mental , Testes Neuropsicológicos , Desempenho Psicomotor , Reconhecimento Psicológico , Adulto Jovem
17.
J Cogn Neurosci ; 30(5): 667-679, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29324072

RESUMO

People can employ adaptive strategies to increase the likelihood that previously encoded information will be successfully retrieved. One such strategy is to constrain retrieval toward relevant information by reimplementing the neurocognitive processes that were engaged during encoding. Using EEG, we examined the temporal dynamics with which constraining retrieval toward semantic versus nonsemantic information affects the processing of new "foil" information encountered during a memory test. Time-frequency analysis of EEG data acquired during an initial study phase revealed that semantic compared with nonsemantic processing was associated with alpha decreases in a left frontal electrode cluster from around 600 msec after stimulus onset. Successful encoding of semantic versus nonsemantic foils during a subsequent memory test was related to decreases in alpha oscillatory activity in the same left frontal electrode cluster, which emerged relatively late in the trial at around 1000-1600 msec after stimulus onset. Across participants, left frontal alpha power elicited by semantic processing during the study phase correlated significantly with left frontal alpha power associated with semantic foil encoding during the memory test. Furthermore, larger left frontal alpha power decreases elicited by semantic foil encoding during the memory test predicted better subsequent semantic foil recognition in an additional surprise foil memory test, although this effect did not reach significance. These findings indicate that constraining retrieval toward semantic information involves reimplementing semantic encoding operations that are mediated by alpha oscillations and that such reimplementation occurs at a late stage of memory retrieval, perhaps reflecting additional monitoring processes.


Assuntos
Ritmo alfa , Encéfalo/fisiologia , Rememoração Mental/fisiologia , Semântica , Adolescente , Adulto , Potenciais Evocados , Feminino , Humanos , Masculino , Adulto Jovem
19.
Clin Chem ; 64(3): 586-596, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29208661

RESUMO

BACKGROUND: Diagnosis of Cushing syndrome requires a multistep process that includes verification of hypercortisolism followed by identification of the cause of adrenocortical hyperfunction. This study assessed whether pituitary, ectopic, and adrenal subtypes of Cushing syndrome were characterized by distinct plasma steroid profiles that might assist diagnosis. METHODS: In this retrospective cross-sectional study, mass spectrometric measurements of a panel of 15 plasma steroids were applied to 222 patient samples tested for Cushing syndrome. Disease was excluded in 138 and confirmed in 51 patients with pituitary Cushing syndrome, 12 with ectopic adrenocorticotropin secretion, and 21 with adrenal disease. Another 277 age- and sex-matched hypertensive and normotensive volunteers were included for comparison. RESULTS: Compared with patients without disease, the largest increases in plasma steroids among patients with Cushing syndrome were observed for 11-deoxycortisol (289%), 21-deoxycortisol (150%), 11-deoxycorticosterone (133%), corticosterone (124%), and cortisol (122%). Patients with ectopic disease showed the most prominent increases, but there was considerable variation for other steroids according to subtype. Patients with adrenal disease had the lowest concentrations of androgens, whereas those with ectopic and pituitary disease showed the lowest concentrations of aldosterone. Plasma 18-oxocortisol was particularly low in ectopic disease. With the use of 10 selected steroids, subjects with and without different Cushing syndrome subtypes could be discriminated nearly as closely as with the use of salivary and urinary free cortisol, dexamethasone-suppressed cortisol, and plasma adrenocorticotropin (9.5% vs 5.8% misclassification). CONCLUSIONS: Patients with different subtypes of Cushing syndrome show distinctive plasma steroid profiles that may offer a supplementary single-test alternative for screening purposes.


Assuntos
Síndrome de Cushing/sangue , Síndrome de Cushing/diagnóstico , Esteroides/sangue , Adolescente , Hormônio Adrenocorticotrópico/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromatografia Líquida/métodos , Estudos Transversais , Feminino , Humanos , Hidrocortisona/análise , Hidrocortisona/urina , Masculino , Metaboloma , Pessoa de Meia-Idade , Estudos Retrospectivos , Esteroides/metabolismo , Espectrometria de Massas em Tandem/métodos
20.
Gynecol Endocrinol ; 34(1): 20-24, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28937294

RESUMO

Pheochromocytomas in pregnancy are rare but potentially lethal. Even rarer is the combination of pheochromocytoma in pregnancy with subsequent development of ectopic Cushing's syndrome. We report a 36-year-old woman, previously diagnosed with essential hypertension, who developed severe hypertension in pregnancy complicated by insulin-dependent gestational diabetes. A cesarean section was performed at 32 weeks following a hypertensive crisis after routine administration of betamethasone. Postnatal persistence of signs and symptoms of catecholamine excess led to the diagnosis of a left adrenal pheochromocytoma. Between diagnosis and planned tumor removal, the patient developed signs and symptoms of Cushing's syndrome (facial edema and hirsutism, myopathy and fatigue). Biochemical testing confirmed hypercortisolism with extremely elevated levels of plasma adrenocorticotropin, urinary cortisol and multiple steroids of a plasma panel that were all normal at previous testing. The previously noradrenergic tumor also started producing epinephrine. Histopathological examination confirmed the pheochromocytoma, which was also immunohistochemically positive for adrenocorticotropin. Full post-surgical recovery was sustained with normal blood pressure and biochemical findings after one year. This report not only underlines the chameleon behavior of pheochromocytoma but also illustrates its potential for a metamorphosing presentation. Corticosteroid administration in pregnancy requires a cautious approach in patients with hypertension.


Assuntos
Neoplasias das Glândulas Suprarrenais/complicações , Síndrome de Cushing/complicações , Hipertensão/complicações , Feocromocitoma/complicações , Período Pós-Parto , Complicações Neoplásicas na Gravidez/diagnóstico , Neoplasias das Glândulas Suprarrenais/fisiopatologia , Hormônio Adrenocorticotrópico/análise , Hormônio Adrenocorticotrópico/sangue , Adulto , Betametasona/administração & dosagem , Betametasona/efeitos adversos , Cesárea , Síndrome de Cushing/diagnóstico , Diabetes Gestacional/diagnóstico , Diabetes Gestacional/fisiopatologia , Feminino , Humanos , Hidrocortisona/urina , Hipertensão/induzido quimicamente , Recém-Nascido , Recém-Nascido Prematuro , Feocromocitoma/patologia , Feocromocitoma/cirurgia , Gravidez , Complicações Neoplásicas na Gravidez/patologia , Complicações Neoplásicas na Gravidez/cirurgia , Resultado da Gravidez
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