Circulating levels of brain-derived neurotrophic factor: correlation with mood, cognition and motor function

Brain-derived neurotrophic factor (BDNF) is the most widely distributed neurotrophin in the CNS, where it plays several pivotal roles in synaptic plasticity and neuronal survival. As a consequence, BDNF has become a key target in the physiopathology of several neurological and psychiatric diseases. Recent studies have consistently reported altered levels of BDNF in the circulation (i.e., serum or plasma) of patients with major depression, bipolar disorder, Alzheimer`s disease, Huntington`s disease and Parkinson`s disease. Correlations between serum BDNF levels and affective, cognitive and motor symptoms have also been described. BDNF appears to be an unspecific biomarker of neuropsychiatric disorders characterized by neurodegenerative changes.

Emotions at multiple levels: An integration

Weiss and Isen have provided many supportive comments about the multi-level perspective, but also found limitations. Isen noted the importance of integrating affect, cognition, and motivation. Weiss commented similarly that the model lacked an integrating “thread.” He suggested that, to be truly multilevel, each level should constrain processes at other levels, and also provide guidance for the development of new concepts. Weiss also noted that the focus on biological processes was a strength of the model. I respond by suggesting that these very biological processes may constitute the “missing” thread. To illustrate this, I discuss some of the recent research on emotions in organizational settings, and argue that biology both constrains and guides theory at each level of the model. Based on this proposition, I revisit each of the five levels in the model, to demonstrate how this integration can be accomplished in this fashion. Finally, I address two additional points: aggregation bias, and the possibility of extending the model to include higher levels of industry and region.

The pyramidal cell in cognition: A comparative study in human and monkey

Here we present evidence that the pyramidal cell phenotype varies markedly in the cortex of different anthropoid species. Regional and species differences in the size of, number of bifurcations in, and spine density of the basal dendritic arbors cannot be explained by brain size. Instead, pyramidal cell morphology appears to accord with the specialized cortical function these cells perform. Cells in the prefrontal cortex of humans are more branched and more spinous than those in the temporal and occipital lobes. Moreover, cells in the prefrontal cortex of humans are more branched and more spinous than those in the prefrontal cortex of macaque and marmoset monkeys. These results suggest that highly spinous, compartmentalized, pyramidal cells (and the circuits they form) are required to perform complex cortical functions such as comprehension, perception, and planning.

Social cognition, language acquisition and the development of the theory of mind

Theory of Mind (ToM) is the cognitive achievement that enables us to report our propositional attitudes, to attribute such attitudes to others, and to use such postulated or observed mental states in the prediction and explanation of behavior. Most normally developing children acquire ToM between the ages of 3 and 5 years, but serious delays beyond this chronological and mental age have been observed in children with autism, as well is in those with severe sensory impairments. We examine data from Studies of ToM in normally developing children and those with deafness, blindness, autism and Williams syndrome, as well as data from lower primates, in a search for answers to key theoretical questions concerning the origins, nature and representation of knowledge about the mind. In answer to these, we offer a framework according to which ToM is jointly dependent upon language and social experience, and is produced by a conjunction of language acquisition with children's growing social understanding, acquired through conversation and interaction with others. We argue that adequate language and adequate social skills are jointly causally sufficient, and individually causally necessary, for producing ToM. Thus our account supports a social developmental theory of the genesis of human cognition, inspired by the work of Sellars and Vygotsky.

Impact of leadership style and emotions on subordinate performance

This article examines whether the emotions of frustration and optimism mediate, fully or partially, the relationship between leadership style and subordinate performance in the context of structural equation modeling. The findings show that transformational leadership has a significant direct influence on frustration and optimism, with the negative influence of frustration having a stronger effect on performance than the positive influence of optimism. Frustration and optimism are found to have a direct influence on performance, and the emotions, frustration and optimism, fully mediate the relationship between transformational leadership and performance. Thus, the effect of transformational leadership style on performance is significant, but indirect. (C) 2002 Elsevier Science Inc. All rights reserved.

Cortex, cognition and the cell: New insights into the pyramidal neuron and prefrontal function

Arguably the most complex conical functions are seated in human cognition, the how and why of which have been debated for centuries by theologians, philosophers and scientists alike. In his best-selling book, An Astonishing Hypothesis: A Scientific Search for the Soul, Francis Crick refined the view that these qualities are determined solely by cortical cells and circuitry. Put simply, cognition is nothing more, or less, than a biological function. Accepting this to be the case, it should be possible to identify the mechanisms that subserve cognitive processing. Since the pioneering studies of Lorent de No and Hebb, and the more recent studies of Fuster, Miller and Goldman-Rakic, to mention but a few, much attention has been focused on the role of persistent neural activity in cognitive processes. Application of modern technologies and modelling techniques has led to new hypotheses about the mechanisms of persistent activity. Here I focus on how regional variations in the pyramidal cell phenotype may determine the complexity of cortical circuitry and, in turn, influence neural activity. Data obtained from thousands of individually injected pyramidal cells in sensory, motor, association and executive cortex reveal marked differences in the numbers of putative excitatory inputs received by these cells. Pyramidal cells in prefrontal cortex have, on average, up to 23 times more dendritic spines than those in the primary visual area. I propose that without these specializations in the structure of pyramidal cells, and the circuits they form, human cognitive processing would not have evolved to its present state. I also present data from both New World and Old World monkeys that show varying degrees of complexity in the pyramidal cell phenotype in their prefrontal cortices, suggesting that cortical circuitry and, thus, cognitive styles are evolving independently in different species.

Being happy, healthy and whole watching movies that affect our emotions

This paper discusses the power of emotions in our health, happiness and wholeness, and the emotional impact of movies. It presents iFelt, an interactive video application to classify, access, explore and visualize movies based on their emotional properties and impact.

Metacognitive and social cognition training (MSCT) in schizophrenia: a preliminary efficacy study

Psychosocial interventions have proven to be effective in treating social cognition in people with psychotic disorders. The current study aimed to determine the effects of a metacognitive and social cognition training (MSCT) program, designed to both remediate deficits and correct biases in social cognition. Thirty-five clinically stable outpatients were recruited and assigned to the MSCT program (n = 19) for 10 weeks (18 sessions) or to the TAU group (n = 16), and they all completed pre- and post-treatment assessments of social cognition, cognitive biases, functioning and symptoms. The MSCT group demonstrated a significant improvement in theory of mind, social perception, emotion recognition and social functioning. Additionally, the tendency to jump to conclusions was significantly reduced among the MSCT group after training. There were no differential benefits regarding clinical symptoms except for one trend group effect for general psychopathology. The results support the efficacy of the MSCT format, but further development of the training program is required to increase the benefits related to attributional style.

Gender Differences in Spatial Cognition: Wayfinding Performance and Sketch Mapping Activity of German Speakers

Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies

The influence of burden of care and perceived stigma on expressed emotions of relatives of stable persons with schizophrenia in Nigerian semi-urban/urban settings

RESUMO: Schizophrenia’s burden defines experience of family members and is associated with high level of distress. Courtesy stigma, a distress concept, worsens caregivers’ burden of care and impacts on schizophrenia. Expressed emotion (EE), another family variable, impacts on schizophrenia. However, relationship between EE, burden of care and stigma has been little explored in western literature but not in sub-Saharan Africa particularly Nigeria. This study explored the impact of burden of care and courtesy stigma on EE among caregivers of persons with schizophrenia in urban and semi-urban settings in Nigeria. Fifty caregivers each from semi-urban and urban areas completed a socio-demographic schedule, family questionnaire, burden interview schedule and perceived devaluation and discrimination scale. The caregivers had a mean age of 42 (± 15.6) years. Majority were females (57%), married (49%), from Yoruba ethnic group (68%), monogamous family (73%) and Christians (82%). A higher proportion of the whole sample (53%) had tertiary education. Three out of ten were sole caregivers. Seventy three (73%) lived with the person they cared for. The average number of hours spent per week by a caregiver with a person with schizophrenia was 35 hours. The urban sample had significantly higher proportion of carers with high global expressed emotion (72.7%) than the semi-urban sample (27.3%). The odds of a caregiver in an urban setting exhibiting high expressed emotion are 4.202 times higher than the odds of caregiver in a semi-urban setting. Additionally, there was significance difference between the urban and semi-urban caregivers in discrimination dimension. High levels of subjective and objective burden were associated with high levels of critical comments. In conclusion, this study is the first demonstration of urban-semi-urban difference in expressed emotion in an African country and its findings provide further support to hypothesized relationship between components of EE and burden of care.

Validação e aplicação clínica de uma escala de cognição social na esquizofrenia = Validation and clinical use of a measure of social cognition in schizophrenia

RESUMO: A cognição social encontra-se frequentemente alterada na esquizofrenia. Esta alteração relaciona-se com a diminuição do funcionamento social,caracterizando-se quer por défices quer por vieses cognitivos sociais. No entanto, existem poucos instrumentos fiáveis e válidos para avaliar a cognição social na esquizofrenia, nomeadamente capazes de medir os vieses cognitivos sociais e a cognição social auto-relevante. Adicionalmente, as bases biológicas da disfunção social não estão totalmente esclarecidas. Evidências recentes sugerem que o peptídeo oxitocina (OXT) influencia o funcionamento social, e que esta relação poderá ser mediada pela cognição social. Este Trabalho de Projecto descreve a contribuição do autor para o desenvolvimento e avaliação psicométrica inicial de um novo instrumento de avaliação da cognição social, e a utilidade desta escala na investigação das associações entre a OXT e a capacidade e vieses cognitivos sociais. A Waiting Room Task (WRT), uma escala constituída por 26 vídeos sequenciais que simulam a experiência de observar outra pessoa numa sala de espera, foi administrada num estudo transversal com 61 doentes com esquizofrenia e 20 controlos saudáveis. Observou-se uma menor capacidade cognitiva social e um aumento dos vieses cognitivos sociais nos doentes com esquizofrenia, comparativamente aos controlos. Nos controlos e doentes com delírios, o desempenho na WRT correlacionou-se significativamente com os níveis de OXT. Esta correlação não se observou nos doentes sem delírios, sugerindo que o papel da OXT na cognição social poderá encontrar-se atenuado neste grupo. Estes achados fornecem suporte inicial para a adequação da WRT como instrumento de avaliação da cognição social na esquizofrenia, podendo ainda ser útil na investigação da sua base biológica. ------------ ABSTRACT: Social cognition is often impaired in schizophrenia. This impairment is related to poor social functioning and is characterized by both social cognitive deficits and biases. However, there are few reliable and valid measures of social cognition in schizophrenia, particularly measures of social cognitive bias and of self-relevant social cognition. Also, the biological bases of social dysfunction are not well understood. Emerging evidence suggests that the peptide oxytocin (OXT) influences social functioning, and that this relationship may be mediated by social cognition. This Research Project describes the author’s contribution to the development and initial psychometric testing of a new measure of social cognition, and the utility of this instrument to examine associations between OXT and social cognitive capacity and bias. The Waiting Room Task WRT), a video-based test comprising 26 sequential videos simulating the experience of facing another person in a waiting room, was administered in a cross-sectional study involving 61 patients with schizophrenia and 20 healthy controls. Social cognitive capacity was lower and social cognitive bias was increased in patients with schizophrenia compared with controls. Among controls and patients with delusions, performance on the WRT was significantly correlated with OXT level. This correlation was not found in patients without delusions suggesting that OXT’s role in social cognition may be blunted in this group. These findings provide initial support for the adequacy of the WRT as a measure for assessing social cognition in schizophrenia that may also be useful in understanding its biological underpinnings.