Cognitive skill | EPFL Graph Search

Cognitive skills, also called cognitive functions, cognitive abilities or cognitive capacities, are brain-based skills which are needed in acquisition of knowledge, manipulation of information and reasoning. They have more to do with the mechanisms of how people learn, remember, solve problems and pay attention, rather than with actual knowledge. Cognitive skills or functions encompass the domains of perception, attention, memory, learning, decision making, and language abilities. Specialisation of functions Cognitive science has provided theories of how the brain works, and these have been of great interest to researchers who work in the empirical fields of brain science. A fundamental question is whether cognitive functions, for example visual processing and language, are autonomous modules, or to what extent the functions depend on each other. Research evidence points towards a middle position, and it is now generally accepted that there is a degree of modularity in aspec

Dynamics of brain function in preterm-born young adolescents

Lorena Gonçalves de Alcântara e Freitas Krikler

Preterm birth is a major risk factor for neurodevelopment impairments often only appearing later in life. The brain is still at a high rate of development during adolescence, making this a promising window for intervention. It is thus crucial to understand the mechanisms of altered brain function in this population. The aim of this thesis is to investigate how the brain dynamically reconfigures its own organisation over time in preterm-born young adolescents. Research to date has mainly focused on structural disturbances or in static features of brain function in this population. However, recent studies have shown that brain activity is highly dynamic, both spontaneously and during performance of a task, and that small disruptions in its complex architecture may interfere with normal behaviour and cognitive abilities. This thesis explores the dynamic nature of brain function in preterm-born adolescents in three steps: First, we investigate changes in spontaneous brain activity over time using a resting-state paradigm. Here, we study how the variability of the blood oxygenation level dependent signal (BOLD), a measure previously linked to cognitive performance, develops in a preterm- and a term-born groups. We find that preterm participants show an altered trajectory of BOLD variability development during early adolescence. We also show that the dynamic patterns of co-activation with the dorsal anterior cingulate cortex (ACC), a key node of the salience network, also develop differently between the preterm and control groups. Secondly, we examine task-driven changes in brain activation. To this end, we select a reality filtering task known to engage the orbitofrontal cortex (OFC), a region that is particularly vulnerable in the preterm. We find that, although the preterm group is able to perform the task successfully, OFC activation is significantly higher in the control participants. Finally, inspired by the successful field of dynamic functional connectivity which has mainly flourished in resting-state paradigms, we develop a novel method to look into task-driven modulations of brain connectivity in a time-resolved way. We then apply this new approach to a third data set involving a movie watching and emotion regulation task. We find several subtle but significant seed; task; and group effects that characterise each of the dynamic co-activation patterns. In short, we introduce a method for time-resolved evaluation of task-driven changes in brain connectivity and provide evidence of altered brain dynamics in preterm-born young adolescents. Our results thus highlight the importance of considering the dynamic aspects of brain function when studying clinical populations.

EPFL2020

The out-of body experience: precipitating factors and neural correlates

Olaf Blanke, Silvia Bünning

Out-of-body experiences (OBEs) are defined as experiences in which a person seems to be awake and sees his body and the world from a location outside his physical body. More precisely, they can be defined by the presence of the following three phenomenological characteristics: (i) disembodiment (location of the self outside one's body); (ii) the impression of seeing the world from an elevated and distanced visuo-spatial perspective (extracorporeal, but egocentric visuo-spatial perspective); and (iii) the impression of seeing one's own body (autoscopy) from this perspective. OBEs have fascinated mankind from time immemorial and are abundant in folklore, mythology, and spiritual experiences of most ancient and modern societies. Here, we review some of the classical precipitating factors of OBEs such as sleep, drug abuse, and general anesthesia as well as their neurobiology and compare them with recent findings on neurological and neurocognitive mechanisms of OBEs. The reviewed data suggest that OBEs are due to functional disintegration of lower-level multisensory processing and abnormal higher-level self-processing at the temporo-parietal junction. We argue that the experimental investigation of the interactions between these multisensory and cognitive mechanisms in OBEs and related illusions in combination with neuroimaging and behavioral techniques might further our understanding of the central mechanisms of corporal awareness and self-consciousness much as previous research about the neural bases of complex body part illusions such as phantom limbs has done.

Elsevier2005

Dynamics of brain function in preterm-born young adolescents

Lorena Gonçalves de Alcântara e Freitas Krikler

EPFL2020