Linguistic neuroprogramming

Late in evolution, one particular brain structure and one particular cognitive function undergo enormous development: the first is the prefrontal cortex and the second is language.  As this article argues, the two are intimately related.  In the human, the prefrontal cortex reaches the size of almost one-third of the entire cortex; especially striking is the exponential evolutionary growth of prefrontal fibers and connections, well beyond the growth they reach in the large apes.  At the same time, precisely because of that extraordinary growth in cortical connectivity, the primitive communication ability of the ape becomes language in the human. Thus, the question of the evolutionary continuity or discontinuity of either prefrontal function or language becomes moot.  There is indeed a quantitative progression from animal to man in the development of the function of the prefrontal cortex and in the ability to communicate cognition and emotion; but the progression is so large and “sudden”, and exponentially so steep, that for all practical purposes both are step functions, qualitatively new and uniquely human

Constructing the context through goals and schemata: top-down processes in comprehension and beyond

My main purpose here is to provide an account of context selection in utterance understanding in terms of the role played by schemata and goals in top-down processing. The general idea is that information is organized hierarchically, with items iteratively organized in chunks—here called “schemata”—at multiple levels, so that the activation of any items spreads to schemata that are the most accessible due to previous experience. The activation of a schema, in turn, activates its other components, so as to predict a likely context for the original item. Since each input activates its own schemata, conflicting schemata compete with (and inhibit) each other, while multiple activations of a schema raise its likelihood to win the competition. There is therefore a double movement—with bottom-up activation of schemata enabling top-down prediction of other contextual components—triggered by multiple sources. Another claim of the paper is that goals are represented by schemata placed at the highest-levels of the executive hierarchy, in accordance with Fuster’s model of the brain as a hierarchically organized perception action cycle. This account can be considered, in part at least, a development of ideas contained in Relevance Theory, though it may imply that some other claims of the theory are in need of revision. Therefore, a secondary purpose of the paper is a contribution to the analysis of that theory

Age-Related Changes in Visual Spatial Working Memory Cognits: Frontal-Parietal EEG Coherence During Delay

This study explored changes in scalp electrophysiology across two Working Memory (WM) tasks and two age groups. Continuous electroencephalography (EEG) was recorded from 18 healthy adults (18-34 years) and 12 healthy adolescents (14-17) during the performance of two Oculomotor Delayed Response (ODR) WM tasks; (i.e. eye movements were the metric of motor response). Delay-period, EEG data in the alpha frequency was sampled from anterior and parietal scalp sites to achieve a general measure of frontal and parietal activity, respectively. Frontal-parietal, alpha coherence was calculated for each participant for each ODR-WM task. Coherence significantly decreased in adults moving across the two ODR tasks, whereas, coherence significantly increased in adolescents moving across the two ODR tasks. The effects of task in the adolescent and adult groups were large and medium, respectively. Within the limits of this study, the results provide empirical support that WM development during adolescence include complex, qualitative, change

Emotion, motivation, decision-making, the orbitofrontal cortex, anterior cingulate cortex, and the amygdala

The orbitofrontal cortex and amygdala are involved in emotion and in motivation, but the relationship between these functions performed by these brain structures is not clear. To address this, a unified theory of emotion and motivation is described in which motivational states are states in which instrumental goal-directed actions are performed to obtain rewards or avoid punishers, and emotional states are states that are elicited when the reward or punisher is or is not received. This greatly simplifies our understanding of emotion and motivation, for the same set of genes and associated brain systems can define the primary or unlearned rewards and punishers such as sweet taste or pain. Recent evidence on the connectivity of human brain systems involved in emotion and motivation indicates that the orbitofrontal cortex is involved in reward value and experienced emotion with outputs to cortical regions including those involved in language, and is a key brain region involved in depression and the associated changes in motivation. The amygdala has weak effective connectivity back to the cortex in humans, and is implicated in brainstem-mediated responses to stimuli such as freezing and autonomic activity, rather than in declarative emotion. The anterior cingulate cortex is involved in learning actions to obtain rewards, and with the orbitofrontal cortex and ventromedial prefrontal cortex in providing the goals for navigation and in reward-related effects on memory consolidation mediated partly via the cholinergic system

Craneología funcional y evolución humana: relaciones estructurales y organización espacial en la evolución de las áreas fronto-parietales

Los humanos modernos se caracterizan por la forma globular del neurocráneo y retracción de la cara, atribuidos generalmente a la encefalización. La proximidad entre cara y cerebro podría implicar un conflicto espacial entre órbitas y lóbulos frontal y temporal. El abultamiento parietal puede deberse a cambios en la corteza parietal, por ejemplo, el precúneo. Esta tesis investiga la relación estructural cerebro-orbital y la anatomía del lóbulo parietal utilizando morfometría geométrica aplicada a imágenes biomedicas de humanos modernos y fósiles y de primates no humanos. Los resultados apuntan hacia un mayor conflicto estructural de las órbitas con los lóbulos temporales. Los lóbulos parietales son longitudinal y verticalmente más grandes en humanos modernos que en neandertales. La variación de la proporción longitudinal del precúneo se debe sobre todo a la región superior y es específica de humanos modernos. La dimensión vertical del precúneo está relacionada con la morfología del contorno parietal exterior.Modern humans are characterized by a globular braincase and a reduced face, two features that are generally attributed to encephalization. The anatomical proximity between the face and the brain involves nonetheless spatial conflicts between the orbits and the frontal and temporal lobes. Parietal bulging is likely due to changes in parietal cortical elements, like the precuneus. This thesis investigates the orbit-brain structural relationships and parietal lobe anatomy through geometric morphometrics and biomedical imaging, in modern and fossil humans, as well as in non-human primates. Results point to a greater structural conflict between orbits and temporal lobes. The parietal lobes are longitudinally and vertically larger in modern humans, when compared to those of Neanderthals. The variation in the longitudinal proportions of the precuneus is mostly due to the superior regions, and it is specific to modern humans. Precuneus vertical dimension is related to the morphology of the outer parietal contour

From context to connectomes: understanding differences in ongoing thought in the laboratory and daily life

Previous work indicates that ongoing thought varies between contexts and that the adaptive nature of different features of thought depends on the context in which they emerge. However, prior investigations have primarily examined specific features of thought in a limited range of laboratory tasks. In doing so, they do not consider the multidimensional and heterogeneous nature of thought, nor reflect the many and varied situations we encounter in everyday life. Accordingly, a core aim of this thesis was to use Multidimensional Experience Sampling (MDES) to empirically map different patterns of thought across a wider range of situations to build a more comprehensive account of context-dependent cognition. In parallel, this thesis capitalises on contemporary methods to map differences in thought to differences in neural architecture to understand the distributed mechanisms supporting different forms of thought, allowing us to go beyond describing experiences. By examining MDES data collected before and during the UK’s first COVID-19 lockdown, Study 1 highlights that daily activities play an important role in shaping patterns of thought and that differences in age moderate thought-situation relationships. By examining MDES data collected in the laboratory while watching videos and in daily life during the COVID-19 pandemic, Study 2 identified a generalisable pattern of socio-emotional and future-directed problem-solving that consistently emerges under conditions of uncertainty. Finally, Study 3 suggests that past-related thought and problem-solving at rest differentially predict the relative functional integration and segregation of unimodal systems (visual and sensorimotor). This thesis, therefore, demonstrates the utility of MDES for building a comprehensive account of cognition since it can be used to understand between- and within-person differences in ongoing thought across a wide range of situations, understanding that can be leveraged in the future to understand how thought-situation relationships contribute to aspects of wellbeing and how the brain supports these experiences

COGNITIVE CONTROL, EVOLUTIONARY GAMES, AND LIE ALGEBRAS

In recent years, pursuit-based feedback control laws have helped realize complex spatio-temporal behaviors of robot collectives by utilizing relative information (e.g. optic flow) of the target with respect to the pursuer. For instance, these algorithms can enable a team of Unmanned Aerial Vehicles (UAVs) perform search, rescue and surveillance. However, such platforms are far from being completely autonomous and frequently require human intervention to reset the goals for the mission midstream, to be accomplished by choosing one from a pool of control laws. While this can ensure achievement of very specific goals over a short duration, such as reaching a search location and performing motions to cover an annular region around it, there is a need to autonomously generate high level goals especially in the face of adverse or unexpected events. This requires using sensory information gathered from the environment in which the agents operate to decide the next course of action. The broad aim of this thesis is to establish a mathematical framework to enable a collective of robotic agents, each with a finite set of actions to choose from, arrive at a cognitive decision that is justified by aggregated evidence. We motivate the use of models from evolutionary game theory, particularly the replicator dynamics, to model the evolution of the probabilities associated with choosing each action. We take inspiration from neuroscience for realizing context-dependent decision making by means of a three-layer cognitive hierarchy operating at multiple timescales. We show how evolutionary game theory offers a natural framework to model this hierarchy. In particular, replicator dynamics associated to fitness maps capture the evolution of a finite number of population fractions or probabilities that grow depending on the fitness or reward obtained for each population type. In the present setting, we interpret the types as synonymous with strategies implemented by feedback laws and the decision of an autonomous agent as represented by probabilities over its strategies. This formulation can be used to realize a combination of available control laws that will enable the agent to achieve its goal. In the bottom layer are the dynamics of an agent which responds to external stimuli from the physical environment at a fast timescale by a combination of its feedback laws. In the intermediate layer is the replicator dynamics evolving in a comparatively slower timescale, in which the decision making that goes behind choosing the feedback law in the lower layer is updated using knowledge of the fitness of each strategy. In the top layer evolving at the slowest timescale, we consider replicator control systems specified by control laws that seek to realize context dependence (cognition) at the higher level. The contributions of this thesis are in all three layers of the cognitive hierarchy, explained through a top-down approach. We first consider the top layer by extending the replicator dynamics to a replicator control system whose controls vary the fitness of strategies in a time-dependent manner. We show a Lie algebraic structure in the space of fitness maps. We exploit this mathematical structure in the dynamics to modulate the fitness so that an arbitrary final set of probabilities can be attained from an initial state. In the process, we determine the associated controllability conditions. In the intermediate layer, we highlight an optimizing property of the replicator dynamics by showing that it satisfies first order necessary conditions for optimality for an appropriate cost function. In the bottom layer, we consider the interpretations of mixed strategies in the agent's physical world. An instance of dyadic pursuit in which the pursuer aims to capture a target using the motion camouflage pursuit strategy while trading off the accuracy of sensory information for the speed of response to the stimuli is explored. In the final part of this thesis, we consider a cognitive description of starling flocks by treating each flock as a single decision-making entity. We use observations made from several flocking events and formulate a data smoothing problem using the game-theoretic formulation in this thesis to understand the temporal evolution of fractions of the relative kinetic energy allocated to the different behavioral modes. We propose a function, the optimal cost arising out of the solution to an underlying optimal control problem, as a measure of cognitive effort involved in producing these behaviors. Lastly, we conclude with a discussion on ongoing work, some challenges and future research directions

Humanity from African Naissance to Coming Millennia

Humanity From African Naissance to Coming Millennia arises out of the world's first Dual Congress that was held at Sun City (South Africa) in 1998 that refers to a conjoint, integrated meeting of two international scientific associations, the International Association for the Study of Human Palaeontology - IV Congress - and the International Association of Human Biologists. The volume includes 39 refereed papers covering a wide range of topics, from Human Biology, Human Evolution (Emerging Homo, Evolving Homo, Early Modern Humans), Dating, Taxonomy and Systematics, Diet, Brain Evolution, offering the most recent analyses and interpretations in different areas of evolutionary anthropology.Humanity From African Naissance to Coming Millennia arises out of the world's first Dual Congress that was held at Sun City (South Africa) in 1998 that refers to a conjoint, integrated meeting of two international scientific associations, the International Association for the Study of Human Palaeontology - IV Congress - and the International Association of Human Biologists. The volume includes 39 refereed papers covering a wide range of topics, from Human Biology, Human Evolution (Emerging Homo, Evolving Homo, Early Modern Humans), Dating, Taxonomy and Systematics, Diet, Brain Evolution, offering the most recent analyses and interpretations in different areas of evolutionary anthropology