Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 4 uppsatser.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.

Thesis (Ph. D.)--West Virginia University, 1999. / Title from document title page. Document formatted into pages; contains xiv, 223 p. : ill. Vita. Includes abstract. Includes bibliographical references (p. 187-220).

Fatores como o tempo de espera ou o risco a ser enfrentado por uma recompensa maior têm um efeito importante e, por vezes, paradoxal no processo de tomada de decisão. O Capítulo I apresenta uma discussão teórica sobre a tomada de decisão mediada por esses dois fatores, bem como sua interligação com o conceito de impulsividade e o Transtorno de Déficit de Atenção e Hiperatividade (TDAH). O Capítulo II oferece uma aplicação desses conceitos em um modelo animal do espectro da Síndrome Alcoólica Fetal, condição que apresenta algumas características semelhantes ao TDAH. Utilizando ratos expostos ao álcool no período pré-natal, duas tarefas de tomada de decisão mediada por tempo ou probabilidade foram usadas para testar se esses animais apresentam diferenças em seus padrões de escolha. Não foram encontradas diferenças significativas entre grupos controle e experimentais. Futuros estudos com outros protocolos, espécies e/ou linhagens são desejáveis. / Factors such as the time to wait, or the risk to be faced for a bigger reward have an important and, sometimes, paradoxical effect on the decision making process. Chapter I presents a theoretical discussion about decision making mediated by these two factors, as well as how they relate to the concept of impulsivity and the Attention-Deficit Hyperactivity Disorder (ADHD). Chapter II offers a practical application of these concepts in an animal model of the spectrum of Fetal Alcohol Syndrome, a condition that presents some similar characterstics in comparison to ADHD. Using rats prenatally exposed to ethanol, two decision making tasks, mediated by time or probability, were used to test if these animals show any difference in their patterns of choice. No significant differences were found between control and experimental groups. Future studies with other protocols, species and/or strains are desirable.

Fatores como o tempo de espera ou o risco a ser enfrentado por uma recompensa maior têm um efeito importante e, por vezes, paradoxal no processo de tomada de decisão. O Capítulo I apresenta uma discussão teórica sobre a tomada de decisão mediada por esses dois fatores, bem como sua interligação com o conceito de impulsividade e o Transtorno de Déficit de Atenção e Hiperatividade (TDAH). O Capítulo II oferece uma aplicação desses conceitos em um modelo animal do espectro da Síndrome Alcoólica Fetal, condição que apresenta algumas características semelhantes ao TDAH. Utilizando ratos expostos ao álcool no período pré-natal, duas tarefas de tomada de decisão mediada por tempo ou probabilidade foram usadas para testar se esses animais apresentam diferenças em seus padrões de escolha. Não foram encontradas diferenças significativas entre grupos controle e experimentais. Futuros estudos com outros protocolos, espécies e/ou linhagens são desejáveis. / Factors such as the time to wait, or the risk to be faced for a bigger reward have an important and, sometimes, paradoxical effect on the decision making process. Chapter I presents a theoretical discussion about decision making mediated by these two factors, as well as how they relate to the concept of impulsivity and the Attention-Deficit Hyperactivity Disorder (ADHD). Chapter II offers a practical application of these concepts in an animal model of the spectrum of Fetal Alcohol Syndrome, a condition that presents some similar characterstics in comparison to ADHD. Using rats prenatally exposed to ethanol, two decision making tasks, mediated by time or probability, were used to test if these animals show any difference in their patterns of choice. No significant differences were found between control and experimental groups. Future studies with other protocols, species and/or strains are desirable.

Fatores como o tempo de espera ou o risco a ser enfrentado por uma recompensa maior têm um efeito importante e, por vezes, paradoxal no processo de tomada de decisão. O Capítulo I apresenta uma discussão teórica sobre a tomada de decisão mediada por esses dois fatores, bem como sua interligação com o conceito de impulsividade e o Transtorno de Déficit de Atenção e Hiperatividade (TDAH). O Capítulo II oferece uma aplicação desses conceitos em um modelo animal do espectro da Síndrome Alcoólica Fetal, condição que apresenta algumas características semelhantes ao TDAH. Utilizando ratos expostos ao álcool no período pré-natal, duas tarefas de tomada de decisão mediada por tempo ou probabilidade foram usadas para testar se esses animais apresentam diferenças em seus padrões de escolha. Não foram encontradas diferenças significativas entre grupos controle e experimentais. Futuros estudos com outros protocolos, espécies e/ou linhagens são desejáveis. / Factors such as the time to wait, or the risk to be faced for a bigger reward have an important and, sometimes, paradoxical effect on the decision making process. Chapter I presents a theoretical discussion about decision making mediated by these two factors, as well as how they relate to the concept of impulsivity and the Attention-Deficit Hyperactivity Disorder (ADHD). Chapter II offers a practical application of these concepts in an animal model of the spectrum of Fetal Alcohol Syndrome, a condition that presents some similar characterstics in comparison to ADHD. Using rats prenatally exposed to ethanol, two decision making tasks, mediated by time or probability, were used to test if these animals show any difference in their patterns of choice. No significant differences were found between control and experimental groups. Future studies with other protocols, species and/or strains are desirable.

Abstract Psychotic disorders usually become evident during adolescence and early adulthood and are commonly preceded by psychosis risk states. Young people at risk for developing psychosis may already have cognitive deficits. This research examined factors associated with psychosis risk and adverse cognitive performance, particularly in those at risk for developing psychosis. We aimed to characterise genetic risk factors for psychosis risk and adverse cognitive performance. Additionally, early and later biological risk markers for adverse cognitive performance and psychosis risk were explored. Two longitudinal birth cohorts, the Northern Finland Birth Cohort 1986 (NFBC 1986, n=6,985 at 16 years) and Avon Longitudinal Study of Parents and Children (ALSPAC, n=5,217 at 17 years), two NFBC 1986 sub-studies, the Oulu Brain and Mind 1 (n=182 for these analyses) and Oulu Brain and Mind 2 (n=471 for these analyses) studies, and two Irish case control studies, the Adolescent Brain Development (n=212) and Challenging Times (n=211) studies, were utilised. Predictors of interest were selected Single Nucleotide Polymorphisms (SNPs at COMT, BDNF and DRD2), prenatal exposure to maternal cigarette smoking (PEMCS) and adolescent metabolic measures. Though not directly associated with psychotic experiences, the COMT-Val158Met Val-Val genotype interacted with experience of childhood trauma to predict more psychotic experiences. Two DRD2 SNPs were associated with poorer cognitive performance, though only in those with risk for psychotic disorders. PEMCS was associated with adult vocabulary and matrix reasoning performance in males, though not in males with adolescent psychotic experiences. Adolescent academic performance, but not psychotic experiences, were associated with metabolic measures, especially with ratios of omega-3 to total fatty acids. These findings impact on prevention strategies for long-term adverse outcomes. Some risk factors differ for those with psychotic experiences compared to the general population, while others do not. SNPs at COMT and DRD2 may be more relevant in those with psychotic experiences. Interventions targeting these groups may be particularly beneficial. Smoking in pregnancy, however, is harmful to male cognitive performance across the population, suggesting elimination of this risk is more broadly relevant. Fatty acid-related metabolic measures may mark risk for cognitive deficits or may represent a developmental feature that is potentially open to intervention. / Tiivistelmä Psykoottiset häiriöt puhkeavat tavallisesti nuoruusiässä tai varhaisessa aikuisiässä. Varsinaista psykoosijaksoa edeltää usein psykoosialttiusvaihe. Nuoruusiän psykoosialttiusvaiheeseen liittyy kognitiivisia puutoksia. Tässä tutkimuksessa selvitettiin tekijöitä, jotka liittyvät psykoosialttiuteen ja heikkoon kognitiiviseen suoriutumiseen, etenkin nuorilla, jotka olivat psykoosiriskissä. Tutkimuksessa tarkasteltiin psykoosialttiuteen ja heikkoon kognitiiviseen suoriutumiseen liittyviä geneettisiä tekijöitä. Lisäksi tutkittiin biologisia varhaisia ja myöhempiä psykoosialttiutta ja heikkoa kognitiivista suoriutumista ennustavia tekijöitä. Tutkimusaineisto käsitti kaksi pitkittäistä syntymäkohorttia: Pohjois-Suomen syntymäkohortti 1986 (n=6,985 16-vuotiaana) ja englantilainen Avon Longitudinal Study of Parents and Children (ALSPAC, n=5,217 17-vuotiaana) -tutkimukset. Pohjois-Suomen syntymäkohortti 1986:sta analysoitiin kahta ala-otosta eli Aivot ja Mieli I (n=182) ja Aivot ja Mieli II (n=471) tutkimusta. Lisäksi tutkimusaineistoon kuului kaksi irlantilaista tapaus-verrokki tutkimusta: Adolescent Brain Development (n=212) ja Challenging Times (n=211) tutkimukset. Ennustavina tekijöinä tarkasteltiin yhden nukleotidin polymorfismia (Single Nucleotide Polymorphisms, SNP; COMT, BDNF ja DRD2 -geeneissä), äidin raskaudenaikaista tupakointia, lapsuuden traumaattisia kokemuksia ja nuoruusiän metabolisia arvoja. COMT-Val158Met geenin Val-Val genotyyppi ei ollut suoraan yhteydessä psykoottisiin kokemuksiin, mutta yhdessä lapsuuden traumaattisten kokemusten kanssa ennusti suurempaa psykoosioireiden määrää. Kaksi DRD2 SNP-varianttia assosioituivat heikompaan kognitiiviseen suoriutumiseen, vaikkakin vain tutkittavilla jotka olivat psykoosialttiita. Äidin raskaudenaikainen tupakointi ennusti huonompaa kognitiivista suoriutumista pojilla, tosin ei pojilla joilla oli nuoruusiässä psykoosioireita. Metaboliset tekijät, erityisesti omega-3 rasvahapon suhde kokonaisrasvahapon määrään oli yhteydessä koulumenestykseen. Tutkimuksen tulosten perusteella voidaan mahdollisesti suunnitella ennaltaehkäiseviä toimia myöhempien haittojen ehkäisemiseksi. Jotkut tutkituista riskitekijöistä assosioituivat eri tavalla kognitioon psykoosialttiilla kuin yleisväestössä. COMT ja DRD2 geenien variantit psykoosialttiilla saattavat olla keskeisiä. Interventiot nuorille, joilla on nämä variantit ja psykoosioireita, voisivat olla erityisesti hyödyllisiä. Äidin raskauden aikaisen tupakointi ennusti poikien kognitiivista suoriutumista. Äidin raskaudenaikaisen tupakoinnin vähentämisellä olisi suotuinen vaikutus tässäkin suhteessa. Rasvahappoihin liittyvät metaboliset suureet voivat olla riski kognitiivisille puutoksille tai ne voivat merkitä kehityksellistä piirrettä, joka voisi mahdollistaa varhaisen ennaltaehkäisyn.

Iron deficiency (ID) is especially common in pregnant women and may even persist following childbirth. This is of concern in light of reports demonstrating that ID may be sufficient to produce homeostatic dysregulation of other metals, including manganese (Mn). These results are particularly important considering the potential introduction of the Mn-containing gas additive, methyl cyclopentadienyl manganese tricarbonyl (MMT), in various countries around the world. In order to model this potentially vulnerable population, we fed female rats fed either control (35 mg Fe/kg chow; 10 mg Mn/kg chow) or low iron/high-manganese (IDMn; 3.5 mg Fe/kg chow; 100 mg Mn/kg chow) diet, and examined whether these changes had any long-term behavioral effects on the animals' spatial abilities, as tested by the Morris water maze (MWM). We also analyzed behavioral performance on auditory sensorimotor gating utilizing prepulse inhibition (PPI), which may be related to overall cognitive performance. Furthermore, brain and blood metal levels were assessed, as well as regional brain isoprostane production. We found that treated animals were slightly ID, with statistically significant increases in both iron (Fe) and Mn in the hippocampus, but statistically significantly less Fe in the cerebellum. Additionally, isoprostane levels, markers of oxidative stress, were increased in the brain stem of IDMn animals. Although treated animals were indistinguishable from controls in the PPI experiments, they performed less well than controls in the MWM. Taken together, our data suggest that vulnerable ID populations exposed to high levels of Mn may indeed be at risk of potentially dangerous alterations in brain metal levels which could also lead to behavioral deficits.

No description available.

No description available.