The purpose of the current dissertation was to develop a measure of mother’s reward responsivity in parenting. I proposed that deficits in reward responsivity may contribute to maladaptive parenting behaviors, especially among depressed mothers. Reward responsivity is conceptualized as an individual difference in reactivity to pleasurable stimuli and represents a key motivational component that could contribute to the frequency and quality of mothers’ interactions with their infants. To empirically evaluate the link between mother reward responsivity, behaviors towards their infant, and infant behavior outcomes, a measure of reward responsivity in relation to parenting behavior was needed. The current dissertation addressed this need and developed a self-report measure of reward responsivity in parenting named the Mother Inventory of Reward Experience (MIRE). The MIRE was evaluated in two studies: the first study was among 31 adolescent mothers (M = 16.97, SD = 1.22) and the second was among 200 adult mothers (M = 28.45, SD = 5.50). Following guidelines on scale development, the development of MIRE started with an initial item pool of 105 items that were examined for psychometric performance of item mean, item kurtosis and item-total correlations. Seventy-two items were deleted because the mean of the item was at the top or bottom of its range, the kurtosis was above or below the absolute value of three, or the item remainder coefficient was less than 0.3. The remaining 33 items displayed high internal consistency reliability and test re-test reliability over two weeks. Convergent validity was established via a statistically significant correlation with a self-report measure of general reward responsivity. Concurrent validity was established via statistically significant correlations with depressive symptoms, parenting stress, and child behavior. Incremental validity of the MIRE over measures of general reward responsivity was supported via significant predictions of parenting stress, infant positive affectivity, and infant regulatory capacity. These results support the reliability and initial validation of the MIRE. Future directions are presented with a focus on understanding the role of maternal reward responsivity, maternal depression, and parenting behaviors.

Cognitive impairments and changes in the structure and function of related brain regions, namely the prefrontal cortex and striatum, have long been implicated in drug addiction. However, it is unknown whether these abnormalities predate substance abuse, potentially serving as risk factors for dependence, or if they are the consequence of protracted use. To address this question, endophenotype research using stimulant-dependent individuals’ biological siblings has been used to investigate traits implicated in the pathology of addiction. Impairments present in both groups suggest an underlying risk-state for dependence, while additional abnormalities present only in stimulant-dependent individuals reflect potential effects of the drugs themselves. Contrastingly, there are also individuals who use stimulant drugs in a controlled manner without developing dependence. These ‘recreational users’ may lack the underlying traits that comprise a greater risk for dependence, or they might maintain additional protective factors against the development of addiction. Experiments in the first half of this dissertation used functional magnetic resonance imaging to investigate neurocognitive similarities and differences between dependent stimulant users, their non-dependent siblings, recreational users of cocaine, and unrelated healthy control volunteers. In Chapter 2, performance on a colour-word Stroop task was impaired in both stimulant-dependent individuals and their siblings, suggesting an endophenotype of cognitive inefficiency. However, neural activity significantly differed between the groups, indicating additional changes specific to the use of stimulant drugs. In Chapter 3, dependent users showed significant attentional bias to salient stimuli on a cocaine-word Stroop task, with a concurrent increase in prefrontal activation. Conversely, recreational users showed resilience in the face of cocaine cues and a decrease in arousal. Finally, Chapter 4 explored differences in reward sensitivity to both generic and drug-specific reinforcers, comparing the effects of personal and family history of stimulant exposure on a monetary incentive delay task. It is also under debate whether the neurocognitive differences seen in stimulant-dependent individuals are unique to substance abuse, or if parallel changes in behaviour and neurobiology are present in similar addiction-spectrum disorders, such as binge eating leading to obesity. In Chapter 5, stimulant-dependent and obese individuals with binge-eating behaviours showed differences in their substance-specific and general reward responsivity on a novel reward-valuation task. However, in Chapter 6 a similar decline in orbitofrontal cortex grey matter volume in relation to both years of stimulant use and body mass index was identified, implicating an overlap in this area between both conditions. These findings are integrated in Chapter 7, discussing the neurocognitive risk and protective factors that underlie an individual’s vulnerability for addiction, not only to stimulant drugs, but also potentially for other addictive behaviours.

The study of feeding behavior, and in particular the study of subjective hedonic experience and objective measures of motivation, are central to understanding how appetite regulation can be compromised in certain individuals. Furthermore, with an integrated picture of physiological and behavioral changes that can occur as a result of energy deprivation what emerges is a better understanding of how palatable food can disrupt attempts at regulating body weight at lower levels of body energy stores. In Article I, the genetic association study examining a potential role for a dopamine-related polymorphism in weight loss, it was shown that contrary to the main hypothesis there was no association between TaqIA polymorphism and the amount of body weight loss. In Article II, it was shown that palatability and olfaction ratings increased as a result of a 24 hour fast and females demonstrated larger improvements in overall olfactory performance. Initial body weight was positively related to improved odor detection threshold and total odour score (TDI). Using the same population sample as Article II, Article III highlights that higher sensitivity to reward and disinhibition scores correlated with responding for palatable snack food stimuli in the relative-reinforcing value of food (RRV) task, further indicating that RRV has strong ties with impulsivity. There was a demonstrable lack of negative alliesthesia under the fasted condition where, after a 75% increase in ad libitum energy intake (EI) relative to the fed condition, this greater amount of food consumed was still rated as being more palatable than the lesser amounts consumed under the fed condition. In Article IV it was shown that an equicaloric (-25%) energy deficit by diet alone was a greater challenge to appetite regulation and resulted in greater compensatory increases in EI than deprivation by exercise alone. Independent of deprivation modality there were significant improvements in odour threshold scores. TDI score increased only under diet alone; furthermore, the noted increase in mean TDI score was positively related to increased ad libitum EI. The picture that emerges is that, acutely, a complete fast has more pronounced effects on appetite and ad libitum EI than dieting alone, which in turn had greater effects than exercise alone or controls. Also, TDI improved under all three methods of energy deprivation, but moreso under conditions of deprivation by diet alone.

Customer Reward Programs (CRP) have increasingly been used in many industries and markets worldwide with the purpose of gaining customers and retaining their loyalty through repeated purchases in exchange of rewards. Currently, most of the retailers in the Swedish grocery store sector have implemented CRP of different types, from simple discount-based programs to complex multipartnership structures. Previous works have been carried on the competitiveness of the grocery retail market in Sweden, but these haven’t addressed the role of the CRP. Therefore, the objective of this thesis was to analyze the performance of the CRP offered by Ica, Coop, Citygross, Willys and Hemköp from a customer loyalty perspective. The discount store Lidl was also included although they haven’t implemented a CRP. The retailers included in our study covered approximately 93% of the market share in Sweden.   Data was collected through anonymous online surveys that included 12 questions addressed to households living in several Swedish cities. The online surveys allowed us to gather demographics data and info about CRP memberships, purchasing habits, customer loyalty, reward preferences, and customer awareness. In total 134 households replied the survey.   We found high store loyalty among the respondents. However, the strong preference for conveniently located stores indicated that most customers enroll in the CRP to take advantage of the repeated visits they already do to a certain store, which has a favorable location. In other words, we suspect customers become store loyal and then they enroll in the CRP. This attitude is masked as true loyalty but in fact it only implies a behavioral loyalty. Further deeper analysis shall be performed to confirm this finding.   We observed a clear increase of the customer loyalty (measured by share of wallet and purchase frequency) in respondents enrolled in CRP compared to not-enrolled counterparts. Households with children and households with high income had a greater tendency to participate in CRP and these two groups exhibited higher customer loyalty. Our results showed that the package of benefits and rewards offered by the CRP alone does not capture many customers into the CRP. Instead, customers looked for store location, quality and price as the appealing factors to enroll a CRP.   The survey results confirmed the dominance that Ica has over the Swedish grocery retail market. Further analysis combining level of expenditures and frequency of purchase showed that Lidl, Hemköp and Citygross performed quite similar within a group that does not capture great portion of the customer expenditure combined to a low purchase frequency. An output of our research showed that Lidl compete quite well with retailers that have CRP in place like Citygross and Hemköp, or on the contrary, that Hemköp with an advanced CRP does not attract customers sufficiently when compared to Lidl. An analysis based on the double jeopardy effect theory showed that Willys exhibits an “excessive loyalty”. This means, Willys had a higher frequency of purchase and level of expenditure than expected when compared against its market penetration level. Therefore, we identified that Willys overachieve results compared to the others retailers and also to Coop, its closest competitor. We concluded that a CRP with larger benefit scheme does not necessarily increases the customer loyalty to the store. Moreover, boosting CRP with multi-partnership programs that offer several experience rewards (spa, ski resorts, music events and travel tickets) could be inefficient for the grocery retailers since customers feel primarily attracted to immediate rewards related with groceries discounts.

Visual art is important for humans. Most people have an interest in visiting art museums, and they spend both time and money on artworks. Appreciating visual art can have an effect on several psychological states, such as pleasure, emotions of wonder, awe, and the sublime. However, the question of what constitutes an aesthetic experience and what mechanisms that are involved in experiencing visual art, are still not fully understood. The discipline neuroaesthetics, which is a subfield of cognitive neuroscience, investigates the biology behind aesthetic experience and aesthetic appreciation. The aim of this thesis is to give an overview of the neural processes involved in experiencing visual art, and to explore how it could be related to components of emotional well-being. As such, neuroimaging studies addressing aesthetic experience and emotional processing are reviewed and discussed. This thesis found a relationship between the neural processes that operate behind a broad range of positive valanced emotions and aesthetic experience. The findings show that experiencing visual art that are aesthetically appreciated by the viewer, induces feelings of hedonic niceness or pleasant well-being and is associated with increased activity in the reward circuit. How aesthetic appreciation affects our emotional and cognitive states respectively and enhances our physiological and psychological well-being remains to be investigated. Understanding the underlying neurobiological processes involved when experiencing visual art is important due to its implications on positive health and well-being.

Each primary sensory cortex gets input from corresponding primary and secondary thalamic nuclei. While primary thalamic nuclei are characterized by their sensory responses, the degree to which secondary thalamus encodes sensory and non-sensory signals is unknown. In the whisker system, the primary nucleus is the ventral posterior nucleus (VPM) and the secondary nucleus is the posterior medial nucleus (POm). While VPM sends precise whisker touch signals to cortex, POm responses are not well understood. Unlike VPM, POm is interconnected with many cortical areas, including motor cortex and association areas. POm, as a recipient of both bottom-up whisker signals and top-down cortical signals, might integrate touch with contextual signals such as reward or movement. Using two-photon microscopy through a gradient index (GRIN) lens, I have assessed the POm response to touch with multi-whisker passive deflections of different velocities, to reward with water droplets, and to self-movement by measuring whisking and licking. POm activity had weak touch responses and was dominated by self-generated movements. My results suggest that POm is driven by self-movement or the internal state signals that accompany it, such as arousal. Next, I investigated whether these representations change when mice learn sensory-reward associations. I demonstrate that POm activity continues to be dominated by whisking and licking and does not acquire selectivity for reward-associated sensory stimuli. We propose a model in which the representation of movements within POm may facilitate learning sensory features in cortex by creating a window for plasticity around relevant stimuli.

Synaptic plasticity is the process whereby connections between neurons can be altered in an experience dependent manner. For example, drugs of abuse alter plasticity in the ventral tegmental area (VTA) of the midbrain. A large amount of research has been applied to uncovering the mechanism whereby synapses on the reward signaling dopamine cells is altered, however, less is known regarding the VTA inhibitory GABA neurons. Our objective was to examine the ability of GABA neurons to exhibit plasticity, and determine how drugs of abuse could influence it. Here we report a novel type of plasticity of excitatory neurotransmission onto VTA GABA cells. This plasticity is dependent on the metabotropic glutamate receptor 5, to signal for diacylglycerolipase alpha to make the endocannabinoid 2-arachadonoyl glycerol to signal via cannabinoid receptor 1 (CB1). Marijuana and cocaine are drugs of abuse that have been shown to alter the endocannabinoid system. Tetrahydrocannabinol is the active ingredient in marijuana, and is a known agonist of CB1, and cocaine is able to attenuate endocannabinoid signals. We tested the effects of these drugs on VTA GABA plasticity and found that it can be blocked by chronic injections of tetrahydrocannabinol, as well as acute and chronic injections of cocaine. If VTA GABA neurons are depressing excitatory inputs, that could lead to less inhibition onto VTA dopamine cells, and therefore, more reward signaling in the brain. This new type of plasticity could be an additional mechanism whereby cocaine and marijuana exert their rewarding and addictive effects. Another brain structure known to exhibit use-dependent plasticity is the hippocampus, which is involved in learning and memory. The stratum oriens is a layer of inhibitory interneurons in the hippocampus that is involved in feedback inhibition onto the principle excitatory cells in the stratum pyramidale. Our goal was to determine whether oriens interneurons were capable of producing an endocannabinoid signal, and if so, whether they could influence plasticity. We identified 2 major subtypes of oriens interneurons, oriens lacunosum-moleculare cells, and parvalbumin-positive basket cells, which are capable of receiving and producing an endocannabinoid signal. Furthermore, we demonstrated that one such endocannabinoid, anandamide, is responsible for signaling for synaptic plasticity. This plasticity is also dependent on CB1, and is unique in that there are few examples of CB1 signaling for potentiation rather than depression. Collectively, these experiments demonstrate two mechanisms of endocannabinoid mediated synaptic plasticity, which could influence reward signaling, addiction and memory.

Attention-deficit/hyperactivity disorder (ADHD) is characterized by hyperactivity, impulsive behavior, and excessive in attention. The diagnosis is divided into different types of ADHD depending on the symptoms. A single cause for the diagnosis has not been found; therefore, various models exist. When choosing between an immediate smaller reward and a later larger reward, ADHD-diagnosed individuals often choose the immediate smaller reward, termed choice impulsivity (CI). Several models have tried to explain this phenomenon. One theory argues that the subjective value of the reward diminishes when the reward is moved furtheraway in time. Others claim that it is a deficit in inhibitory-based executive dysfunction and that ADHD individuals cannot suppress the drive and resist the temptation of the earlier reward. The delay aversion model argues that it is a motivational problem with an abnormality in the reward mechanism making the patients hypersensitive to delayed rewards. The negative affective state that evokes from the delayed rewards makes them want to escape or avoid it and therefore choose the small, immediate reward. The insula and the amygdala mediate both negative and positive emotional processes in the brain and are candidates for this phenomenon. In this systematic review, four scientific studies were selected and included to investigate if the insula and amygdala are the primary CI candidates in ADHD-diagnosed individuals. The systematic review results support the idea that the amygdala correlates with CI in ADHD-diagnosed individuals, therefore supporting the delay aversion model theory of ADHD. A correlation between insula and CI in ADHD-diagnosed individuals could not be established in this systematic review. Understanding the role that emotional structures have in ADHD can help to develop interventions or therapy to cope with the disadvantaged features of ADHD.

The present study was designed to examine the relationship between the success of self-reinforcement (as defined by its effectiveness in increasing a given response) and a specific aspect of positive self-esteem that would seem most clearly related to the effectiveness of self-reinforcement, valuing one’s own opinions and judgements highly. Self-esteem implies a positive feeling or attitude about oneself. One factor involved in the acquisition of this positive attitude is the level of the individual’s confidence in the legitimacy of his own opinions. The more confident a person is that his opinions are of value, the more likely it is he will have a high self-esteem.

Everyday people seek pleasant experiences, acting in ways they believe will lead to emotional gratification. By engaging with the world people learn about which actions lead to certain outcomes and use this information to navigate their environment. Ultimately, this knowledge helps people to improve their decision-making in order to increase positive emotions.This paper seeks to investigate this process of learning about and seeking out pleasant experiences. To understand the choices people make, I propose a theoretical framework of decision-making based on two components: learning and emotions. Reinforcement learning provides a computational model for how agents receive information from the environment about the outcome of different actions. This form of learning is coupled with psychological theories of emotion, explaining how affect plays an important role in shaping decisions.The paper describes research conducted to empirically test the validity of this approach. In the experiment, participant affect was measured during a gambling task in which participants made decisions under uncertainty. Results from the study suggest that people do in fact have affective responses to choice outcomes, and that they are able to utilize this information to improve decision-making.