Scientific research on free will was started by Libet et al. (1982). They detected that thereadiness potential (RP) proceeded urges with up to 350ms. One interpretation of the RP wasthat it represented motor planning. The research progress of antecedent brain activity inrelation to conscious urges is investigated by looking at contemporary studies. How differentassumptions and definitions of the free will concept influences interpretation of these studiesis also discussed. The evidence is in favor that the RP is not representing motor planning.Antecedent activity has been detected with numerous technologies, most notably fMRIclassifiers which have been used to predict decisions in advance. Scrutiny of these resultsreveals that the experimental setups are dependent on time-locking trials which may construethe results. It is shown that predictions based on probabilistic antecedents can be interpretedin numerous ways. The review shows that free will positions differ from each other onseveral factors, such as whether free will is either-or or exists on a spectrum. Some notablepositions are not dependent on antecedent activity at all. The notion of control is one of thepivotal factors deciding if a subject experience free will, not if they are the causer per se.Future discussion will be improved by systematizing the differences between the free willpositions and communicating them clearly. Convergent evidence points at the explanatorymodel of free will being a cognitive feeling – A feeling which reports ownership over actionsbut does not cause them.

Why do we need to sleep? Not only is getting enough sleep important for our overall health and well-being, it is perhaps of utmost importance for normal brain functioning. Scientific findings derived from studying sleep deprivation suggests that sleep also plays an important role in our emotional functioning, which has led researchers to propose a causal and intimate relationship between sleep and emotional brain functioning. Without sleep it seems as our emotional processing become impaired in various ways. Along with advances in cognitive neuroscience, it is now possible to characterize mechanisms underlying emotional brain processes. In pursuit of the possible functions of sleep, researchers have also proposed that rapid eye movement sleep, might support a process of affective brain homeostasis and recalibration that optimally prepares the organism for next-day social and emotional functioning. This thesis reviews current behavioral and neurophysiological evidence focused on the relationship between sleep and emotional brain functioning, and the role of rapid eye movement sleep in emotional processing.

Grupper och grupprestationer har studerats länge utifrån olika perspektiv och discipliner, vilket har gett upphov till ett flertal teorier och förklaringsmodeller som innefattar olika tillvägagångssätt för hur grupper kan studeras. I denna uppsats förklaras begreppen grupper, grupprocesser och grupprestationer utifrån olika perspektiv och discipliner innan ett neurovetenskapligt perspektiv på grupper och grupprestationer antas. Detta för att redogöra för hur kognitiv neurovetenskap och neurovetenskapliga mätmetoder som electroencephalography (EEG) och functional magnetic resonance imaging (fMRI) kan förhålla sig till forskning på grupper, grupprocesser och grupprestationer. Syftet med uppsatsen är att beskriva hur grupper kan studeras utifrån ett neurovetenskapligt perspektiv samt hur kognitiv neurovetenskap kan komplettera studier på grupper och grupprestationer. Först presenteras en förklaring på vad grupper, grupprocesser och grupprestationer är, inklusive en redogörelse för relevanta begrepp som ledarskap, gruppsammanhållning och gruppkognition. Detta följs sedan av hur grupper och grupprestationer kan studeras ytterligare med ett neurovetenskapligt perspektiv, för att avslutas med problematik och möjligheter för kognitiv neurovetenskap inom forskningsfältet.

Punishment is the act of penalizing an individual as a response to a transgression. This thesis will deal with punishment in experimental game scenarios and in experimental criminal punishment scenarios, along with their different adaptations. The aim will be to provide an overview of both psychological and neurological underpinnings of punishment by reviewing existing literature. While punishment ought to deter transgressions and promote cooperative behavior, internal neural reward-related systems seem to be a driving factor of the desire to punish wrongdoings. Decisions on whether a transgressor is guilty and deserves punishment is mediated by the medial prefrontal cortex with an emphasis on the ventromedial parts. External influences affect the behavioral output and its underlying neural signatures of punishment. Social context such as peer pressure and in-group bias emphasize the importance of theory of mind related areas when conducting punishment.

Resilience refers to the fact that some individuals cope well with stressful experiences. Many factors contribute to this sort of resilience, such as the early environment, the serotonin transporter gene (5-HTTPLR), the hypothalamic-pituitaryadrenal (HPA) axis, the sympathetic-adrenal medullary (SAM) axis, and emotion regulation techniques. The aim of this thesis is to investigate which factors contribute to resilience, with a particular focus on the emotion regulation technique of cognitive reappraisal. The results show that the prefrontal cortex (PFC) and amygdala each play a crucial role when it comes to stress regulation. Studies have found that the PFC inhibits the amygdala response, but that the PFC is vulnerable to exposure to chronic stress. As a result, the PFC might fail to inhibit the amygdala response. Individuals who use cognitive reappraisal techniques – which has been associated particularly with frontal and parietal brain activity – seem to be less prone to this sort of problem, and, as a result, more resilient to stress.

Our memory is prone to distortions which in everyday life can lead to mistaken memories. This thesis investigates memory distortion. In addition, one might recall (e.g. an event) correctly but misremember the source of the event (e.g. place or time of the event); this particular type of memory distortion is called source amnesia. Here, an overview of cognitive theories of memory distortion as well as the neuroscience behind memory distortion is provided. In addition, the particular memory distortion of source amnesia where one is unable to acquire when or where a fact was learned is further investigated. Results indicate that an overlap of qualities related to the information being learned causes information to be linked to wrong sources, thus creating distorted memories. Misinformation is also indicated to produce impairment in memory. In memory distortions, memory impairments are representative in various areas of the brain, including the hippocampus and the amygdala in the medial temporal lobes as well as in the frontal cortex and in the visual cortex. These key areas are also closely related to brain aging in Alzheimer´s disease and in schizophrenia, depression, posttraumatic stress disorder (PTSD) and in drug and alcohol abuse. Individuals inflicted with these disease symptoms seem to be more prone to source amnesia compared to controls. The limitations and future directions of what we can study regarding memory distortion and source amnesia are also presented in this thesis.

Cocaine is known for its severe addictive properties and still, there is no effective treatment for cocaine addiction. Cocaine is a powerful chemical substance. It enters the brain rapidly and cause abnormal high levels of dopamine. Dopamine is found to be the neural correlate for reward. Addictive drugs such as cocaine are reported to be rewarding and initially generate many dimensions of positive effects. However, repeated cocaine use are associated with both structural and functional abnormalities in several brain regions, especially in areas responsible for voluntary control. Loss of control gives way to compulsive consumption and craving for more cocaine stimulation. These neuronal changes and negative symptoms tend to occur gradually, while the tolerance increases. The addicted individual has to enhance the dose in order to obtain the desired effect, which is; becoming physically dependent of a substance. Also, dysregulation of reward circuitries causes decreased sensitivity to natural rewards leading to increased interest in cocaine-related reward stimulation. The abstinence usually last for long time, even years, after self-administration, which makes addicts highly sensitive to relapse. Up to date, effective therapeutic interventions and pharmacological treatments are limited. Neurostimulation techniques such as DBS have shown positive results in regulation of dopaminergic excitability. Though, more research in the complexity of dopamine and mesolimbic areas is well needed, in order to better understand the neural basis of cocaine addiction and be able to offer evidence-based treatments. This thesis will provide an overview of the neuronal impact of cocaine on the dopaminergic reward circuitries in the brain.

Menopause is a major reproductive-related event in a woman’s life, occurring naturally at around the age of fifty years. Accompanying menopause is a drastic decrease in estrogen levels. Estrogen receptors are present throughout the human brain: e.g., in regions such as the hippocampus and prefrontal cortex, both involved in cognition. Given that about half of the world’s population is female, it is important to examine if and how cognition is affected by the menopausal estrogen depletion, both at the level of public health, and at the individual level. Studies within the field show diverse results due to a wide range of methodology among studies. Behavioral studies foremost point towards a potential estrogenic effect on verbal short- and long-term memory. Structural and functional neuroimaging, together with animal studies, mainly show structural and functional alterations in the hippocampus and prefrontal cortex that may be related to changes in estrogen levels. Taken together, this thesis reviews estrogenic effects on different cognitive functions, as well as structural and functional changes in the brain in relation to the menopausal estrogen depletion.

Alzheimers sjukdom (AS) är den vanligaste orsaken till demens hos personer över 65 års ålder. Skador i det centrala nervsystemet byggs upp under lång tid och leder till bl.a. nedsatt episodiskt minne, vilket är det vanligaste debutsymptomet. Kemper et al. (1993) analyserade den syntaktiska komplexiteten i skrivna meningar för att se i vilken grad dessa meningar kunde användas för att avgöra sjukdomsgrad hos patienter som genomgått en minnesutredning. Patienterna kunde i 89 % av fallen kategoriseras till rätt sjukdomsgrad enbart utifrån den syntaktiska komplexiteten. Målet med denna pilotstudie var att pröva fyra syntaktiska komplexitetsmått (dependenslängd, idétäthet, verbtäthet och antal ord) i skrivna meningar som diagnostiska markörer för AS. Samtliga fyra mått bidrog till att särskilja AS-patienter från en kontrollgrupp (sensitivitet 86 %, specificitet 62 %). Med reservation för att kontrollgruppen hade lägre ålder och högre utbildningsnivå indikerar denna studie att de analyserade komplexitetsmåtten är värda att undersöka vidare.

As opposed to earlier beliefs, the brain is altering itself throughout an individual’s life. The process of functional or structural alterations is referred to as plasticity, and can be induced by several factors such as experience or physical exercise. In this thesis, the research area of experience-dependent plasticity, with focus on exercise-induced plasticity is examined critically. Evidence from a vast array of studies are reviewed and compared in order to find whether physical exercise can induce neural plasticity in the human brain, how it may be beneficial, and what some of the plausible mediators of exercise-induced plasticity are. The findings demonstrated in this thesis suggest that although there are knowledge gaps and limitations in the literature, physical exercise can indeed result in exhibited plasticity as well as being beneficial for the human brain in several ways.