Schema and value: Characterizing the role of the rostral and ventral medial prefrontal cortex in episodic future thinking

As humans we are not stuck in an everlasting present. Instead, we can project ourselves into both our personal past and future. Remembering the past and simulating the future are strongly interrelated processes. They are both supported by largely the same brain regions including the rostral and ventral medial prefrontal cortex (mPFC) but also the hippocampus, the posterior cingulate cortex (PCC), as well as other regions in the parietal and temporal cortices. Interestingly, this core network for episodic simulation and episodic memory partially overlaps with a brain network for evaluation and value-based decision making. This is particularly the case for the mPFC. This part of the brain has been associated both with a large number of different cognitive functions ranging from the representation of memory schemas and self-referential processing to the representation of value and affect. As a consequence, a unifying account of mPFC functioning has remained elusive. The present thesis investigates the unique contribution of the mPFC to episodic simulation by highlighting its role in the representation of memory schemas and value. In a first functional MRI and pre-registered behavioral replication study, we demonstrate that the mPFC encodes representations of known people as well as of known locations from participants’ everyday life. We demonstrate that merely imagined encounters with liked vs. disliked people at these locations can change our attitude toward the locations. The magnitude of this simulation-induced attitude change was predicted by activation in the mPFC during the simulations. Specifically, locations simulated with liked people exhibited significantly larger increases in liking than those simulated with disliked people. In a second behavioral study, we examined the mechanisms of simulation-based learning more closely. To this end, participants also simulated encounters with neutral people at neutral locations. Using repeated behavioral assessments of participants’ memory representations, we reveal that simulations cause an integration of memory representations for jointly simulated people and locations. Moreover, compared to the neutral baseline condition we demonstrate a transfer of positive valence from liked and of negative valence from disliked people to their paired locations. We also provide evidence that simulations induce an affective experience that aligns with the valence of the person and that this experience can account for the observed attitude change toward the location. In a final fMRI study, we examine the structure of memory representations encoded in the mPFC. Specifically, we provide evidence for the hypothesis that the mPFC encodes schematic representations of our social and physical environment. We demonstrate that representations of individual exemplars of these environments (i.e., individual people and locations) are closely intertwined with a representation of their value. In sum, our findings show that we can learn from imagined experience much as we learn from actual past experience and that the mPFC plays a key role in simulation-based learning. The mPFC encodes information about our environment in value-weighted schematic representations. These representations can account for the overlap of mnemonic and evaluative functions in the mPFC and might play a key role in simulation-based learning. Our results are in line with a view that our memories of the past serve us in ways that are oriented toward the future. Our ability to simulate potential scenarios allows us to anticipate the future consequences of our choices and thereby fosters farsighted decision making. Thus, our findings help to better characterize the functional role of the mPFC in episodic future simulation and valuation

The cognitive neuroscience of visual working memory

Visual working memory allows us to temporarily maintain and manipulate visual information in order to solve a task. The study of the brain mechanisms underlying this function began more than half a century ago, with Scoville and Milner’s (1957) seminal discoveries with amnesic patients. This timely collection of papers brings together diverse perspectives on the cognitive neuroscience of visual working memory from multiple fields that have traditionally been fairly disjointed: human neuroimaging, electrophysiological, behavioural and animal lesion studies, investigating both the developing and the adult brain

Computing the social brain connectome across systems and states

Social skills probably emerge from the interaction between different neural processing levels. However, social neuroscience is fragmented into highly specialized, rarely cross-referenced topics. The present study attempts a systematic reconciliation by deriving a social brain definition from neural activity meta-analyses on social-cognitive capacities. The social brain was characterized by meta-analytic connectivity modeling evaluating coactivation in task-focused brain states and physiological fluctuations evaluating correlations in task-free brain states. Network clustering proposed a functional segregation into (1) lower sensory, (2) limbic, (3) intermediate, and (4) high associative neural circuits that together mediate various social phenomena. Functional profiling suggested that no brain region or network is exclusively devoted to social processes. Finally, nodes of the putative mirror-neuron system were coherently cross-connected during tasks and more tightly coupled to embodied simulation systems rather than abstract emulation systems. These first steps may help reintegrate the specialized research agendas in the social and affective sciences

The drive to control : how affect and motivation regulate cognitive control

The studies described in this thesis aimed to investigate how affect and motivation impact cognitive control, in terms of both behavior and brain activation. Six out of the eight empirical studies found support for indirect effects on cognitive control, as measured with sequential trial-to-trial adaptations in cognitive control tasks. Only two studies resulted in evidence for a direct modulation of cognitive control (Chapter 4 and 9). Indirect effects occurred on trial-to-trial adaptation in cognitive control tasks involving a random presentation of compatible and incompatible trials. We found that conflict adaptation, the transient improvement of behavioral control after incompatible in comparison to compatible trials, was subject to affective regulation. In particular, we found that after incompatible trials, positive emotional states reduced and negative emotional states increased adaptation. These effects occurred for both short-term (Chapters 2 and 3) and long-term affect manipulations (Chapters 5, 6, and 7). Motivation and task difficulty also interacted with conflict adaptation (Chapter 8). The neuroimaging studies described in Chapter 3 and 6 demonstrate the role of fronto-striatal interactions in this affective regulation of cognitive control. Taken together, this thesis demonstrates the role that positive and negative emotions play in the adaptation of behavior and mental effort.LEI Universiteit LeidenFSW - Action Control - OudAction Contro

The neurocognitive processing of plausibility and real-world knowledge:A cross-linguistic investigation

Our knowledge about concepts and meanings is at the very heart of human cognition. In everyday life, we have to interact with our environment in a variety of different ways. Our actions are guided by what we know and believe about the world and this knowledge derives primarily from previous sensory and perceptual experiences. The fact that we are capable of engaging with our environment in an appropriate and efficient way means that we have learnt (how) to make sense of the events and entities we are faced with in day-to-day life. We are thus able to recognise and name both physical objects and abstract concepts, to categorise and associate them based on their specific properties, to interpret other people’s intentions, and to judge cause and effect of their actions as well as our own. Moreover, the ability to represent this wealth of knowledge about the real world in the conceptualised and symbolic form of language is believed to be exclusive to humans. Our language capacity allows us to communicate with others about past and future events or to describe fictitious scenarios by combining previously acquired concepts in a novel way without the need for external stimulation. Thus language forms a primary means of interacting with those around us by allowing us to express our own thoughts and comprehend those of others. As long as language processing proceeds in an undisturbed manner, we are largely unaware of the underlying mechanisms that support the seemingly effortless interpretation of linguistic input. The importance of these processes for successful communication, however, becomes all the more apparent when language processing is disrupted, for example, by brain lesions that render semantic analysis difficult or impossible. Scientific research that aims to uncover and define cognitive or neural mechanisms underlying semantic processing is inevitably faced with the complexity and wealth of semantic relationships that need to be taken into account. In absence of noninvasive neurocognitive methods and insights gleaned from modern neurobiology, early research had a limited impact on our understanding of how semantic processing is implemented in the human brain. Traditional neurological models of language have been based primarily on lesion-deficit data, and thus supported the view that certain areas of the brain were exclusively dedicated to the processing of language-specific functions (Geschwind, 1970; Lichtheim, 1885; Wernicke, 1874). Furthermore, classical theories of sensory processing viewed the brain as a purely stimulus-driven system that retrieves and combines individual low-level aspects or features in an automated, passive and context-independent manner (Biederman, 1987; Burton & Sinclair, 1996; Hubel & Wiesel, 1965; Massaro, 1998). After a recent paradigm shift in the cognitive neurosciences, current theories of sensory processing are now based on the concept of the brain as a highly active, adaptive and dynamic device. In this sense, language comprehension, like many other higher-cognitive functions, is shaped by a flexible interaction of a number of different processes and information sources that include so-called bottom-up signals, i.e., the actual sensory input and processes related to their forward propagation, and top-down processes that generate predictions and expectations based on prior experience and perceived probabilities. Therefore, accounts that view semantic processing as a dynamic and active construction of meaning that is highly sensitive to contextual influences seem most probable from a neurobiological perspective. Results from electrophysiological and neuroimaging research on semantic analysis in sentence and discourse context have provided evidence for top-down influences from the very beginning. In addition, recent ERP results have suggested that the interaction between topdown and bottom-up information is more flexible and dynamic than previously assumed. Yet, the importance of predictions and expectations has long been neglected in models of semantic processing and language comprehension in general. Neuroimaging data have provided us with a long list of brain regions that have been implicated in different aspects of semantic analysis. We are only beginning to understand the role(s) that these regions play and how they interact to support the flexible and efficient construction of meaning. The aim of the present thesis is to gain a more comprehensive view on the computational mechanisms underlying language processing by investigating how bottom- up and top-down information and processes interactively contribute to the semantic analysis in sentences and discourse. To this end, we conducted a total of five studies that used either event-related potentials or functional neuroimaging to shed light on this matter from different perspectives. The thesis is divided into two main parts: Part I (chapters 1-5) provides an overview on previous results from electrophysiology and neuroimaging on semantic processing as well as a description and discussion of the studies conducted in the present thesis. Part II (chapters 6-9) consists of three research articles that describe and discuss the results of five experimental studies. In Part I, Chapter 2 gives a brief introduction to the event-related potential and functional neuroimaging techniques and reviews the most relevant results and theories that have emerged from studies on sentence and discourse processing. Chapter 3 highlights the research questions targeted in each of the experimental studies and describes and discusses the most relevant findings against the background established by Chapter 2. Chapters 4 and 5 conclude Part I by placing the presented results in a broader context and by briefly outlining future directions. Part II begins with a survey of the three studies reported in the subsequent chapters. Chapter 7 highlights the results of the first study, a German ERP experiment that investigated the impact of capitalisation, i.e., a purely form-based and contextually independent bottom-up manipulation, on the processing of semantic anomalies in single sentences. Chapter 8 comprises three ERP experiments that used both easy and hard to detect semantic anomalies in German and English to corroborate the assumption that the weighting of top-down and bottom-up information cues might be determined in a language-specific way. Chapter 9, the final chapter of the thesis, describes and discusses the results of the third study, in which the impact of embedding context on the required depth of semantic processing was examined using functional neuroimaging

The parent?infant dyad and the construction of the subjective self

Developmental psychology and psychopathology has in the past been more concerned with the quality of self-representation than with the development of the subjective agency which underpins our experience of feeling, thought and action, a key function of mentalisation. This review begins by contrasting a Cartesian view of pre-wired introspective subjectivity with a constructionist model based on the assumption of an innate contingency detector which orients the infant towards aspects of the social world that react congruently and in a specifically cued informative manner that expresses and facilitates the assimilation of cultural knowledge. Research on the neural mechanisms associated with mentalisation and social influences on its development are reviewed. It is suggested that the infant focuses on the attachment figure as a source of reliable information about the world. The construction of the sense of a subjective self is then an aspect of acquiring knowledge about the world through the caregiver's pedagogical communicative displays which in this context focuses on the child's thoughts and feelings. We argue that a number of possible mechanisms, including complementary activation of attachment and mentalisation, the disruptive effect of maltreatment on parent-child communication, the biobehavioural overlap of cues for learning and cues for attachment, may have a role in ensuring that the quality of relationship with the caregiver influences the development of the child's experience of thoughts and feelings

Memory Influences Visual Cognition across Multiple Functional States of Interactive Cortical Dynamics

No embargo requiredMemory supports a wide range of abilities from categorical perception to goal-directed behavior, such as decision-making and episodic recognition. Memory activates fast and surprisingly accurately and even when information is ambiguous or impoverished (i.e., showing object constancy). This paper proposes the multiple-state interactive (MUSI) account of object cognition that attempts to explain how sensory stimulation activates memory across multiple functional states of neural dynamics, including automatic and strategic mental simulation mechanisms that can ground cognition in modal information processing. A key novel postulate of this account is ‘multiple-function regional activity’: The same neuronal population can contribute to multiple brain states, depending upon the dominant set of inputs at that time. In state 1, the initial fast bottom-up pass through posterior neocortex happens between 95 ms and ~200 ms, with knowledge supporting categorical perception by 120 ms. In state 2, starting around 200 ms, a sustained state of iterative activation of object-sensitive cortex involves bottom-up, recurrent, and feedback interactions with frontoparietal cortex. This supports higher cognitive functions associated with decision-making even under ambiguous or impoverished conditions, phenomenological consciousness, and automatic mental simulation. In the latest state so far identified, state M, starting around 300 to 500 ms, large-scale cortical network interactions, including between multiple networks (e.g., control, salience, and especially default mode), further modulate posterior cortex. This supports elaborated cognition based on earlier processing, including episodic memory, strategic mental simulation, decision evaluation, creativity, and access consciousness. Convergent evidence is reviewed from cognitive neuroscience of object cognition, decision-making, memory, and mental imagery that support this account and define the brain regions and time course of these brain dynamics

Functional Connectivity of EEG LORETA in Cortical Core Components of the Self and the Default Network (DNt) of the Brain

INTRODUCTION: Recent research exploring cortical functional connectivity defines a default network (DNt) of brain function and activation of a core midline network (CMS) in the processing of self. The electroencephalographic (EEG) activity in these components of the human DNt and CMS is not well understood. METHODS: This study was conducted with 63 participants. Individuals were recorded during eyes-closed (ECB) and eyes-opened (EOB) baselines and active task (AT) conditions (e.g., self-referential, self-image, self-concept, recent symptomology, other face and object processing). We estimated EEG source localization with standardized low resolution electromagnetic tomography (sLORETA). Subjective experience was obtained for baselines and photographic conditions. RESULTS: The ECB resting condition shows higher activity in all frequencies as compared to all other conditions. Likewise, the active tasks show differential effects for increased activity as compared to EOB for each region of interest (ROI) in each frequency domain. CONCLUSION: The data are in agreement with other neuroimaging techniques (fMRI/PET) investigating the DNt of brain function and further shows that the 3-dimensional localization accuracy of LORETA EEG is sufficient for the study of the DNt. In examining both within and between functional core regions there was a higher degree of activity in lower frequency bands during eyes closed; however, this pattern does not extend to all ROIs for all frequency domains. The differences may represent functional connectivity relating to endogenous/exogenous attention states as opposed to the simple concept of “resting” or “non-activity”. Further study of the functional relationships between EEG frequencies within and between regions in the default network and during self-specific processing may prove important to understanding the complex nature of neocortical functional integration