Support from a TMS/MEP study for a direct link between positive/negative stimuli and approach/avoidance tendencies

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Theories and explanations in psychology

Research in psychology has undergone many changes in the last 20 years. The increased and tighter relationship between psychology, neuroscience, and philosophy, the emergence and affirmation of embodied and grounded cognition approaches, the grow of interest on new research topics, the strengthening of new areas, such as the social, cognitive, and affective neuroscience, the spread of Bayesian models, and the recent debates on the replication crisis, represent some of the pieces of the new emerging landscape. In spite of these novelties, one character of the discipline remains stable: its focus on empirical investigation. While we think this is an important and distinctive feature of our discipline, all too often this fascination for empirical data is accompanied by the absence of an equally deep interest for theory development. Noteworthy, while other scientific disciplines are endowed with a theoretical branch—think of the role of “theoretical physics” for physics—psychology does not have an equally institutionalized theoretical branch. This lack of theoretical interest is testified also by the fact that only few journals (Frontiers represents an exception) accept theoretical articles, i.e., articles that systematize existing evidence to inform a model or develop a new theory. Here we argue that a strongly theoretical approach, that takes into account and seeks to identify the mechanisms underlying brain and mental processes, and that aims to build formal theories and computational models, can contribute to address the current limitations of psychological research helping it to face important challenges. In the following we will highlight some limitations of psychological research, that a strong theoretical and philosophically informed approach can contribute to face. 1) Interdisciplinary dialogue. True interdisciplinary research is crucial for our understanding of the mind and brain mechanisms. Initially cognitive science was a highly interdisciplinary project, but part of this original richness has gone lost. Yet, complex phenomena such as mental and cognitive processes can be understood only starting from multiple perspectives. However, integrating these perspectives is all but easy. It is therefore crucial to promote solid and reliable interdisciplinary research. This might be done through the creation of novel interdisciplinary structures/department, or through funding policies that privilege research and projects with interdisciplinary teams (the European Community has done some attempts in this direction). In general, we should aim at increasing and promoting the occasions where researchers from different areas debate, developing a common language. Aside from conferences and workshops, journals with interdisciplinary character and interdisciplinary debates represent a fundamental mean to boost this kind of approach. A pivotal role in promoting interdisciplinarity can be played by philosophy—and in particular by philosophy of mind and language, philosophy of psychology, philosophy of neuroscience, and of cognitive science. Although not a natural science, empirically-informed philosophy can play a crucial integrative role, helping to build a more comprehensive view of the field and identifying links that cross disciplinary boundaries. In a different way, computational models and simulations are instruments that boost interdisciplinarity: a good model has a cumulative character, it helps in theory building and in validation of empirical data coming from different sources and disciplines and obtained with different methods (Caligiore et al., 2010; Pezzulo et al., 2011). 2) Emphasis on theoretical aspects. One of the limitations of psychology, that the relationship with philosophy can help reducing, is the scarce emphasis on theories. Being good scientists in psychology and neuroscience increasingly equates with having good methodological competences, and being able to use many techniques and instruments. While we clearly do not intend to under-evaluate the importance of technical mastery and of methodological rigor and competence, we fear that stressing only these aspects can lead young researchers to focus more on very specific topics and paradigms, thus losing the big picture. Instead, we are convinced that research should be guided by a strong theoretical background: solid theories open new perspectives and research questions and might lead to clear and testable research questions. Prioritizing empirical results over theory can instead lead to a growing tendency to obtain fragmented and conflicting evidence about a phenomenon. Psychology (or at least most of its branches), should mainly remain an experimental discipline. However, scientists who do not possess a comprehensive view and focus only on experimental evidence can be very productive but might not lead to the identification of core principles, useful for a real progress in research. Curiously one of the papers that has more deeply influenced and inspired research in embodied cognition, the BBS paper by Barsalou (1999), was not directly founded on empirical evidence—although it discussed empirical evidence related to some of its claims. One of the most debated issues in recent psychological research is the replication crisis, and in particular the reliability of scientific results. We do not intend to under-evaluate the attempts to strengthen the results and we really appreciate the recent tendency to distinguish confirmatory and exploratory research. We namely think that research in psychology needs to follow two strategies: a more explorative, and a more confirmative one-science has indeed two different sides, a creative and a monitoring one. Exerting either an inductive or a deductive logic might allow to build strong and reliable empirical-based psychological models. However, we think that more resources and more effort should be devoted to find explanations of phenomena [see Van Rooij (2018) for convincing arguments on this]. As argued by Cummins (2000), “a substantial proportion of research effort in experimental psychology isn't expended directly in the explanation business; it is expended in the business of discovering and confirming effects.” Based on these considerations, we believe that more emphasis should be given to the ability to plan and construct experiments with the aim of theory building rather than simply to find reliable effects. Not only the tendency to publish unsound results, but also the tendency to search “originality” at all costs without theory should be contrasted. This approach should clearly impact training, education, and also selection of young researchers. The objective of ascribing a more crucial role to the theoretical foundations of our discipline can be reached in multiple ways. We will mention just a couple of them. One possible strategy is to focus more on core mechanisms, adopting a synthetic approach. As clearly explained by Hommel and Colzato (2017) in a recent grand challenge, a mature science should “learn to value theoretical frameworks that track down core mechanisms in as many phenomena as possible,” and a more parsimonious approach should be promoted. One example is the role played by goals in influencing action representation, imitation, etc. Another way to promote a synthetic approach consists in fostering the use of computational models. Computational models can namely help formulating clearer experimental hypotheses, refining theories, and validating them. Particularly promising are dynamic systems approach, neural networks models, Bayesian models. 3) Epistemological awareness. It is important to understand where the field is going. Recent years have seen a variety of pivotal changes and modifications. The spread of embodied and grounded cognition has represented a real revolution in the areas of cognition and social cognition, and has determined an important paradigm change. In addition, we have assisted to the introduction of extended mind proposals, the increased role of social neuroscience and overall the development of a very tight relationship between psychology and neuroscience, the increased importance of Bayesian models. Experiments in psychology typically support or disconfirm field theories, but in many cases they do not explicitly relate to these more general approaches or theories. We instead believe that it is important for scientists to situate their own research within a broad theoretical framework, a general theory; this can namely help to form a cumulative baggage of knowledge. 4) Key methodological challenges of psychology. The hotly debated replication crisis in science has been particularly deep in psychology. Addressing it in a proper way certainly requires methodological improvements, but also a clear epistemological vision of the specificity of psychological research. The field is divided between scientists who think it is important to address them improving replication, and scientists who think that research should be more focused on innovation and discovery. A strong theoretical approach can provide means to address this crisis, adopting synthetic methods that facilitate the identification of some basic mechanisms rather than focusing on a variety of more or less fashionable effects. It is important to foster debate on this topic, since its outcome may influence the future of our discipline. In addition, it is important to promote the discussion and use of different kinds of computational models, aimed at strengthening theoretical approaches. 5) Cross-cultural research. Scholars are starting to recognize that psychological processes are far from being universal (Henrich et al., 2010; Prinz, 2012; Barrett, 2017; Hruschka et al., 2018). As a consequence, psychologists are starting to propose more and more cross-cultural research. The research instruments we now possess, allowing to perform online experiment, allow scientists to perform more easily studies that include multicultural samples. It is important to promote these practices, encouraging researchers of different nations and backgrounds to collaborate. Old debates, such as that related to the influence of language and languages on cognition, have acquired a new fresh status. A mature reflection on these topics is important and crucial for the development of our discipline. Cross-cultural research should be promoted and fostered. 6) Dear old themes. Some topics are crucial for the understanding of mind, brain, behavior. Unluckily debates on some apparently old-fashioned topics are sometimes abandoned, but focusing on them can offer new insights and open new research venues. A strong theoretical and philosophical approach, firmly based on scientific evidence, can offer fresh perspectives and exciting new ideas on these topics. Some examples include the nature-nurture debate; the role of notions such as simulation and representation for psychological understanding; the mechanisms underlying the ability of abstraction/abstractness in animal and human cognition; how concepts are acquired and represented in the brain; the effects of language on perception, categorization, and thought; our sense of body; the theories of narrative self; the role of interoceptive and emotional experience, of religious experience, of mindfulness; penetrability of cognition/perception; how consciousness work; the mechanisms underlying the formation of beliefs and their influence on decision making; how we represent others, e.g., through stereotypes and implicit biases, comprehend them, e.g., through mindreading and perspective taking, and act with them, e.g., through joint action; how we represent morality, social norms, and institutions. To conclude: How do we dream the psychology of the future? First, we dream of a psychology focusing on theoretically solid, explanation-based accounts, and on the identification of key principles rather than on fashionable effects. Second, we dream of a psychology open to diversity,-characterized by an interdisciplinary approach, and more open to methodological contaminations and to the possibility to perform studies on different populations

How watching Pinocchio movies changes our subjective experience of extrapersonal space

The way we experience the space around us is highly subjective. It has been shown that motion potentialities that are intrinsic to our body influence our space categorization. Furthermore, we have recently demonstrated that in the extrapersonal space, our categorization also depends on the movement potential of other agents. When we have to categorize the space as "Near" or "Far" between a reference and a target, the space categorized as "Near" is wider if the reference corresponds to a biological agent that has the potential to walk, instead of a biological and non-biological agent that cannot walk. But what exactly drives this "Near space extension"? In the present paper, we tested whether abstract beliefs about the biological nature of an agent determine how we categorize the space between the agent and an object. Participants were asked to first read a Pinocchio story and watch a correspondent video in which Pinocchio acts like a real human, in order to become more transported into the initial story. Then they had to categorize the location ("Near" or "Far") of a target object located at progressively increasing or decreasing distances from a non-biological agent (i.e., a wooden dummy) and from a biological agent (i.e., a human-like avatar). The results indicate that being transported into the Pinocchio story, induces an equal "Near" space threshold with both the avatar and the wooden dummy as reference frames

The role of stimulus-driven versus goal-directed processes in fight and flight tendencies measured with motor evoked potentials induced by Transcranial Magnetic Stimulation

This study examines two contrasting explanations for early tendencies to fight and flee. According to a stimulus-driven explanation, goal-incompatible stimuli that are easy/difficult to control lead to the tendency to fight/flee. According to a goal-directed explanation, on the other hand, the tendency to fight/flee occurs when the expected utility of fighting/fleeing is the highest. Participants did a computer task in which they were confronted with goal-incompatible stimuli that were (a) easy to control and fighting had the highest expected utility, (b) easy to control and fleeing had the highest expected utility, and (c) difficult to control and fleeing and fighting had zero expected utility. After participants were trained to use one hand to fight and another hand to flee, they either had to choose a response or merely observe the stimuli. During the observation trials, single-pulse Transcranial Magnetic Stimulation (TMS) was applied to the primary motor cortex 450 ms post-stimulus onset and motor evoked potentials (MEPs) were measured from the hand muscles. Results showed that participants chose to fight/flee when the expected utility of fighting/fleeing was the highest, and that they responded late when the expected utility of both responses was low. They also showed larger MEPs for the right/left hand when the expected utility of fighting/fleeing was the highest. This result can be interpreted as support for the goal-directed account, but only if it is assumed that we were unable to override the presumed natural mapping between hand (right/left) and response (fight/flight)

Embodying an outgroup:the role of racial bias and the effect of multisensory processing in somatosensory remapping

We come to understand other people’s physical and mental states by re-mapping their bodily states onto our sensorimotor system. This process, also called somatosensory resonance, is an essential ability for social cognition and is stronger when observing ingroup than outgroup members. Here we investigated, first, whether implicit racial bias constrains somatosensory resonance, and second, whether increasing the ingroup/outgroup perceived physical similarity results in an increase in the somatosensory resonance for outgroup members. We used the Visual Remapping of Touch effect as an index of individuals’ ability in resonating with the others, and the Implicit Association Test to measure racial bias. In Experiment 1, participants were asked to detect near-threshold tactile stimuli delivered to their own face while viewing either an ingroup or an outgroup face receiving a similar stimulation. Our results showed that individuals’ tactile accuracy when viewing an outgroup face being touched was negatively correlated to their implicit racial bias. In Experiment 2, participants received the Interpersonal Multisensory Stimulation (IMS) while observing an outgroup member. IMS has been found to increase the perceived physical similarity between the observer’s and the observed body. We tested whether such increase in ingroup/outgroup perceived physical similarity increased the remapping ability for outgroup members. We found that after sharing IMS experience with an outgroup member, tactile accuracy when viewing touch on outgroup faces increased. Interestingly, participants with stronger implicit bias against the outgroup showed larger positive change in the remapping. We conclude that shared multisensory experiences might represent one key way to improve our ability to resonate with others by overcoming the boundaries between ingroup and outgroup categories

A CASE-CONTROL STUDY OF NEUROTOXIC METALS IN CEREBROSPINAL FLUID AND RISK OF AMYOTROPHIC LATERAL SCLEROSIS

Many studies have investigated the possible relation between exposure to heavy metals and risk of amyotrophic lateral sclerosis (ALS). We aimed at assessing the levels of two neurotoxic metals, cadmium (Cd), lead (Pb) and mercury (Hg) in cerebrospinal fluid (CSF) of ALS patients and hospital controls. CSF heavy metal content was determined using inductively coupled plasma sector field mass spectrometry (ICP-SF-MS) according to methodologies previously established for biological matrices and specifically for CSF. We obtained CSF samples from 38 ALS cases, including 16 men and 22 women, and from 38 hospital-referred subjects undergoing lumbar puncture because of suspected but later unconfirmed neurological disease, with mean age of 55.5 and 52.26 respectively (range 30\u2013 85). Median heavy metal concentrations were higher in ALS cases compared to controls for Pb (155 vs. 132 ng/l) but lower for Cd (36 vs. 72) and Hg (196 vs. 217). In unconditional multiple logistic regression analysis adjusting for age and sex, we found a disease odds ratio (OR) for the middle and the upper exposure tertiles of 0.8 (0.2-2.6) and 1.4 (95% CI 0.5 to 4.2) for Pb, 0.9 (0.3-2.8) and 0.3 (0.1 to 1.0) for Cd, and 12.4 (2.7-57.3) and 3.03 (0.52-17.55) for Hg. We also conducted sensitivity analyses with log transformed values and with winsorized values by setting data exceeding the 95th percentile to the 95th percentile, but the risk estimates did not substantially change. Our results and particularly the lack of dose-response relations give little support for an involvement of these heavy metals in ALS etiology, with the possible exception of Hg. However, caution should be used in the interpretation of these results due to some study limitations, such as the statistical imprecision of the risk estimates, the hospital-based design of the study, and the potential for unmeasured confounding

Consensus Paper: Current Perspectives on Abstract Concepts and Future Research Directions

Abstract concepts are relevant to a wide range of disciplines, including cognitive science, linguistics, psychology, cognitive, social, and affective neuroscience, and philosophy. This consensus paper synthesizes the work and views of researchers in the field, discussing current perspectives on theoretical and methodological issues, and recommendations for future research. In this paper, we urge researchers to go beyond the traditional abstract-concrete dichotomy and consider the multiple dimensions that characterize concepts (e.g., sensorimotor experience, social interaction, conceptual metaphor), as well as the mediating influence of linguistic and cultural context on conceptual representations. We also promote the use of interactive methods to investigate both the comprehension and production of abstract concepts, while also focusing on individual differences in conceptual representations. Overall, we argue that abstract concepts should be studied in a more nuanced way that takes into account their complexity and diversity, which should permit us a fuller, more holistic understanding of abstract cognition

SerpinA1 levels in amyotrophic lateral sclerosis patients: An exploratory study

Background: SerpinA1, a serine protease inhibitor, is involved in the modulation of microglial-mediated inflammation in neurodegenerative diseases. We explored SerpinA1 levels in cerebrospinal fluid (CSF) and serum of amyotrophic lateral sclerosis (ALS) patients to understand its potential role in the pathogenesis of the disease. Methods: SerpinA1, neurofilament light (NfL) and heavy (NfH) chain, and chitinase-3-like protein-1 (CHI3L1) were determined in CSF and serum of ALS patients (n = 110) and healthy controls (n = 10) (automated next-generation ELISA), and correlated with clinical parameters, after identifying three classes of progressors (fast, intermediate, slow). Biomarker levels were analyzed for diagnostic power and association with progression and survival. Results: SerpinA1serum was significantly decreased in ALS (median: 1032 μg/mL) compared with controls (1343 μg/mL) (p = 0.02). SerpinA1CSF was elevated only in fast progressors (8.6 μg/mL) compared with slow (4.43 μg/mL, p = 0.01) and intermediate (4.42 μg/mL, p = 0.03) progressors. Moreover, SerpinA1CSF correlated with neurofilament and CHI3L1 levels in CSF. Contrarily to SerpinA1CSF , neurofilament and CHI3L1 concentrations in CSF correlated with measures of disease progression in ALS, while SerpinA1serum mildly related with time to generalization (rho = 0.20, p = 0.04). In multivariate analysis, the ratio between serum and CSF SerpinA1 (SerpinA1 ratio) and NfHCSF were independently associated with survival. Conclusions: Higher SerpinA1CSF levels are found in fast progressors, suggesting SerpinA1 is a component of the neuroinflammatory mechanisms acting upon fast-progressing forms of ALS. Both neurofilaments or CHI3L1CSF levels outperformed SerpinA1 at predicting disease progression rate in our cohort, and so the prognostic value of SerpinA1 alone as a measure remains inconclusive