In adult populations, it is generally accepted there is an overall male advantage on spatial tasks and an overall female advantage on verbal tasks. These differences are inconsistent in children. The present study examined relations among age, sex, EEG hemispheric activation, and performance on spatial and verbal tasks. Thirty-two eight-year-olds (16 boys) and 32 college students (16 men) had EEG recorded at baseline and while performing a computerized 2-dimensional Gingerbread Man mental rotation task, a computerized 2-dimensional Alphanumeric mental rotation task, a computerized 3-dimensional Basketball Player mental rotation task, and a computerized Lexical Decision-Making task. Additionally, participants completed a paper-and-pencil Water Level task and an oral Verbal Fluency task. On the 2-dimensional Alphanumeric and 3-dimensional Basketball Player mental rotation tasks men performed better than boys, but the performance of women and girls did not differ. On the Lexical Decision-Making and Water level tasks, men performed better than women, while there was no difference between boys and girls. No sex differences were found on the 2-dimensional Gingerbread Man mental rotation task or Verbal Fluency task. Analyses of task-related data also indicate that computer familiarization or computer related task demands might contribute to sex differences on computerized tasks. EEG analyses indicated that, on the 2-dimensional Alphanumeric mental rotation task, men exhibited more left posterior temporal activation than women, while there were no differences between boys and girls. Additionally, there was evidence that simple, or 2-dimensional, mental rotation tasks are associated with left posterior brain activation, while 3-dimensional mental rotation tasks are associated with right posterior brain activation. On the 2-dimensional Gingerbread Man mental rotation task, males exhibited more activation of the left parietal area than females, while on the 2-dimensional Alphanumeric mental rotation task, men exhibited more activation of the left posterior temporal area than women. On the 3-dimensional Basketball player mental rotation task, all participants exhibited greater activation of the right parietal area than the left parietal area. / Ph. D.

The primary purpose of this study was to investigate the relationship between each of three variables of creativity — Verbal Fluency, Verbal Flexibility, Verbal Originality — and each of nine measures of sensory perception. The nine sensory measures included three visual, three auditory, and three tactual tasks.

Einführung. In der vorliegenden Studie untersuchten wir durch funktionelle Nahinfrarotspektroskopie (fNIRS) präfrontale Hirnoxygenierung während Ableistung von Sprachaufgaben. FNIRS weist über Bestimmung von Konzentrationsunterschieden von sauerstoffbeladenes (OxyHb) und sauerstofffreies Hämoglobin (DeoxyHb) regionale Blutflussänderungen nach und lässt somit validen Rückschluss auf Hirnaktivität zu. Bereits in früheren Studien konnte nachgewiesen werden, dass Patienten mit Alkoholkrankheit verminderte präfrontale Hirnaktivität zeigen. Teil 2 der Studie untersucht den im Untersuchungsgebiet liegenden Schläfenmuskel (musculus temporalis) auf Einflüsse auf die Methode fNIRS. Methoden. Wir verglichen 15 entgiftete Patienten mit Alkoholkrankheit (Patientengruppe, PG) mit passenden 15 gesunden Kontrollprobanden (Kontrollgruppe, KG)bezüglich deren Hirn- und Muskelaktivität während Ableistung Wortflüssigkeitsaufgabe (VFT; engl. Verbal Fluency Task). Bestimmte, insbesondere präfrontale Hirnareale wurden durch phonologische und semantische Testsaufgaben (TA´s), ebenso durch eine Kontrollaufgabe (KA), (Wochentag aufzählen) aktiviert. Durch EMG wurde während Durchführung der Aufgabe die Aktivität des musculus temporalis gemessen. Wir verwendeten zur Datenanalyse sowohl von fNIRS wie auch EMG eine 2x2x2x6 Varianzanalyse (ANOVA) mit Zwischensubjektfaktor „Gruppe“ und Innersubjektfaktoren „Bedingung“, „Seite“ und „Zeit“, gerechnet wurde dies für jeweils Oxy- und DeoxyHb sowie den phonologischen sowie semantischen Teil. Ergebnisse. Beide Gruppen lieferten eine vergleichbare Menge an Worten, Hirnaktivierung zeigte sich bei beiden Gruppen signifikant höher in den Testaufgaben (phonologisch > semantisch). Die PG zeigte verminderte Hirnaktivierung präfrontal im phonologischen, vergleichbare Hirnaktivität im semantischen Teil. Beide Gruppen zeigten vergleichbare Muskelaktivität, jeweils signifikant höher in den jeweiligen Testaufgaben. Es zeigten sich keine systematischen Assoziationen (Korrelation nach Pearson) zwischen fNIRS und EMG. Schlussfolgerungen. Insgesamt konnten vorherige Studien mit Nachweis niedrigerer präfrontaler Hirnoxygenierung bei entgifteten Patienten mit Alkoholkrankheit gegenüber gesunden Kontrollen bestätigt werden. Die Mehraktivierung beider Gruppen während phonologischer Aufgabe gründet in dem höheren intelektuellen Anspruch der Aufgabe, dies erklärt auch den Gruppenunterschied in speziell dieser Aufgabe. Durch eine vergleichbare Muskelaktivität der beiden Gruppen sowie fehlende Assoziationen zwischen fNIRS und EMG sehen wir keinen Einfluss von Muskelaktivität auf die Hirnaktivitätsmessung durch fNIRS. Auch eine valide Untersuchung von psychiatrisch kranken Probandengruppen wie Patienten mit Alkoholkrankheit ist hierdurch gut möglich. Die Studie befürwortet den künftigen Einsatz und weitere methodische Untersuchungen zur Messung mit fNIRS, einem validen, artefaktunempfindlichen, handlichen und relativ günstigen Messinstrument. / Introduction. In this study we examined prafrontal brain oxygenation using functional near infrared spectroscopy (fNIRS) while performing a speech test. Via changes of concentrations of oxygenated (OxyHb) and deoxygenated (DeoxyHb) hemoglobin fNIRS measures regional bloodflow mirroring brain activity. Former studies already showed that detoxified patients with alcohol dependency have lower prefrontal brain activity. In the second part of the study we investigate the temporal muscle, surfacing the measured prefrontal area, in reference to influence on the method fNIRS. Methods. We compared 15 detoxified patients with alcohol dependency (patient group, PG) with the same amount of 15 matching healthy controls (control Goup, CG) regarding their brain and muscle activity during performing a verbal fluency task (VFT). Spezific prefrontal brain areas were activated by executing a phonological and a semantical test task (TT), as comparison we led them perform a control task (CT), reciting weekdays. Via EMG we measured temporal muscle activity while passing the test. For data analysis for both measuring methods (fNIRS and EMG) we used a 2x2x2x6 Analysis of Variance (ANOVA) with the factors “group”, “condition”, “side” and “time”. We calculated these for both Oxy- and DeoxyHb as well as for phonological and semantical test. Results. Both groups announced a comparable amount of words, brain activity was significantly higher while performing th TT (phonological higher than semantical). The PG achieved less activity in prafrontal areas, only in the phonological part, not in the semantical. Both groups performed comparable muscle activity, however activated the temporal muscle more while performing the TT´s. Systematic correlations (Pearson) between fNIRS and EMG weren’t found. Discussion. Overall like in elder studies we could confirm lower prefrontal brain oxygenation on detoxified patients with alcohol dependency compared to matching controls. Reaching higher activity during the phonological task is defined by the exercises higher level of difficulty, which also explains the difference of group result in especially this test. As muscle activity was comparable between the two groups, we couldn’t find associations between fNIRS and EMG. Thus we don’t see muscle activity interfering with the measurement of brain activity using fNIRS. Also this method proofs reliable and valid being used in subjects with psychiatric illnesses like alcohol dependency. This study supports the future Use just like further methodical investigations of fNIRS, a method nonsensitive to artifacts.

The present study seeks to explore if the bilingual advantage and disadvantage of children who are natively bilingual in English and Spanish extends to children who gain exposure to and eventually become bilingual in these languages beginning at ages 5 and 6. Specifically, the study compares executive control, vocabulary, and verbal fluency for three groups of children: a) native Spanish-English bilinguals, b) late bilinguals that have completed at least 5 years of a 50-50 dual language immersion program in English and Spanish in school, and c) English monolinguals that have not had second language instruction. The proposed study seeks a better understanding of the unique cognitive skill sets of native and late bilingual and monolingual children, and to inform educational policy related to bilingual students. / text

Schizophrenia is a complex and severe psychiatric disorder with positive symptoms, negative symptoms and cognitive deficits. Preclinical neurobiological studies showed that alterations of dopaminergic and glutamatergic neurotransmitter circuits involving the prefrontal cortex resulted in cognitive impairment such as working memory. Functional activation and functional connectivity findings of functional Magnetic Resonance Imaging (fMRI) data provided support for prefrontal dysfunction during fMRI working memory tasks in individuals with schizophrenia. However, these findings do not offer a neurobiological interpretation of the fMRI data. Biophysical modelling of functional large-scale networks has been designed for the analysis of fMRI data, which can be interpreted in a mechanistic way. This approach may enable the interpretation of fMRI data in terms of altered synaptic plasticity processes found in schizophrenia. One such process is gating mechanism, which has been shown to be altered for the thalamo-cortical and meso-cortical connection in schizophrenia. The primary aim of the thesis was to investigate altered synaptic plasticity and gating mechanisms with Dynamic Causal Modelling (DCM) within functional large-scale networks during two fMRI tasks in individuals with schizophrenia. Applying nonlinear DCM to the verbal fluency fMRI task of the Edinburgh High Risk Study, we showed that the connection strengths with nonlinear modulation for the thalamo-cortical connection was reduced in subjects at high familial risk of schizophrenia when compared to healthy controls. These results suggest that nonlinear DCM enables the investigation of altered synaptic plasticity and gating mechanism from fMRI data. For the Scottish Family Mental Health Study, we reported two different optimal linear models for individuals with established schizophrenia (EST) and healthy controls during working memory function. We suggested that this result may indicate that EST and healthy controls used different functional large-scale networks. The results of nonlinear DCM analyses may suggest that gating mechanism was intact in EST and healthy controls. In conclusion, the results presented in this thesis give evidence for the role of synaptic plasticity processes as assessed in functional large-scale networks during cognitive tasks in individuals with schizophrenia.

Smell plays a vital role in our daily lives and influences the way we perceive the world around us. People have the excellent ability to detect and distinguish odors, but they usually have difficulty in identifying individual odors. Olfactory abilities (olfactory identification, olfactory detection and olfactory discrimination) also differ significantly interindividually. In general, however, women achieve better results. While a number of studies point to sex differences in olfactory perception, especially in the identification of odors, we need to understand sex only as an overarching concept that includes specific factors such as hormonal influences or different odor experiences that can actually influence olfactory abilities. One of them could be verbal fluency, which allows us to recall information from memory, as there are studies showing the link between the ability to identify odors and verbal fluency. The main aim of the thesis was to test whether the difference between males and females in the identification of odors is mediated by a sex difference in verbal fluency. The secondary aim of the thesis was to explore whether the connection of odor identification and verbal fluency varies according to which form of verbal fluency is tested (phonetic or semantic), and whether these tests can be...

EEG activation studies suggest cerebral lateralization of emotions with greater left than right prefrontal activation during positive mood states and greater right than left prefrontal activation during negative mood states (Davidson et al., 1990). Cerebral lateralization is also observed in cognitive tasks, with verbal fluency associated with left frontal activation and design fluency associated with right frontal activation (Baldo et al., 2001). Further, there are lateralized associations between emotion and cognition; that is, verbal fluency is positively associated with induced positive mood, whereas design fluency is positively associated with induced negative mood (Bartolic et al., 1999). The current study expected naturally occurring mood states to be differentially associated with performance on executive function fluency tasks, and based on previous findings (Cabeza, 2002), that age would moderate the association between emotion and fluency. Results suggest a trend for a positive association between positive affect (PA) and verbal fluency. Age did not moderate associations between emotion and cognitive tasks, although greater interdependence between cognitive and emotion variables in older relative to middle-aged adults suggests decreased lateralization in older adults; however differences in interdependence between older and younger adults were negligible. These results suggest that PA may positively influence some areas of cognition, although age may not moderate these results. Sample and measurement limitations may have contributed to this finding.

The development of category knowledge is in part a function of one's experiences with the world. The types of errors produced during category generation tasks may reveal the boundaries of these experiences and the ways in which they are organized into lexical networks. Examining the errors made by bilingual children with and without language impairment (LI) and bilingual adults may help to distinguish the effects of ability versus experience on the development and organization of lexical-semantic categories. The purpose of this study was to examine the types of errors made by bilingual (Spanish-English) children with (n=37) and without (n=35) LI and bilingual adults (n=26) on category generation tasks in both their languages and at two category levels: taxonomic and slot-filler. Results revealed a main effect for level (taxonomic vs. slot-filler) and error type (semantic vs. other) and suggest that bilingual seven to nine-year-old children's and adults' proportions and types of errors produced on category generation tasks differ significantly based on ability (i.e., TD or LI) but not on experience (i.e., TD or Adults). / text

The purpose of the present study was to explore whether the phonological encoding difficulties that have been demonstrated in children who stutter persist in adults whose stuttering persists. This hypothesis was investigated by comparing the phonological working memory of adults who stutter (AWS) and adults who do not stutter (AWNS) using non-word repetition and phoneme elision tasks. Twenty-four adults (age range = 17;9 to 46;11 mean age = 28;2): 12 AWS and 12 AWNS matched on gender and age participated in this study. A total of 48 non-words consisting of an equal number (N = 12 per syllable length category) of two-syllable, three-syllable, four-syllable and seven-syllable non-words were selected for use in the non-word repetition and phoneme elision tasks. In the non-word repetition task, results showed a significant interaction between fluency group and syllable length for the 7-syllable length category only, indicating that AWS require a significantly higher mean number of attempts than AWNS. Results of the phoneme elision task revealed a significant main effect for syllable length with both groups demonstrating a significant reduction in accuracy as the non-words increased in length, but there was no significant interaction between fluency group and syllable class length. Potential implications of these findings are presented along with recommendations for future research. / text

Evidence suggests that cerebral blood flow patterns accompanying a mental activity are retained in many locked-in patients. Thus, real-time monitoring with functional transcranial Doppler (TCD) together with a specific mental task could control a brain-computer interface (BCI), thereby providing self-initiated interaction. The objective of this study was to create an automatic detection algorithm to differentiate hemodynamic responses coincident with one's performance of verbal fluency (VF) versus counting tasks. We recruited 10 healthy adults who each silently performed up to 30 VF tasks and counted between each. Both middle cerebral arteries were simultaneously imaged using TCD. Linear Discriminant Analyses (LDA) successfully differentiated between VF and both prior and post counting tasks. For every participant, LDA achieved the 70% classification accuracy sufficient for BCIs. Results demonstrate automatic detection of a VF task by TCD and warrant further investigation of TCD as a BCI.