Search

Transcranial magnetic stimulation (TMS) is a non-invasive technique that can transiently interfere with local cortical functioning, thus enabling inferences of causal left AG involvement in higher functions from experimentation with healthy participants. Here, we examine 35 studies that measure behavioural outcomes soon after or during targeting TMS to the left AG, by design and as documented by individual magnetic resonance images, in healthy adult participants. The reviewed evidence suggests a specific causal involvement of the left AG in a wide range of tasks involving language, memory, number processing, visuospatial attention, body awareness and motor planning functions. These core findings are particularly valuable to inform theoretical models of the left AG role(s) in higher functions, due to the anatomical specificity afforded by the selected studies and the complementarity of TMS to different methods of investigation. In particular, the variety of the operations within and between functions in which the left AG appears to be causally involved poses a formidable challenge to any attempts to identify a single computational process subserved by the left AG (as opposed to just outlining a broad type of functional contribution) that could apply across thematic areas. We conclude by highlighting directions for improvement in future experimentation with TMS, in order to strengthen the available evidence, while taking into account the anatomical heterogeneity of this brain region.

When Gerstmann published the case report which later became known as the first case of Gerstmann syndrome, he did not claim the discovery of a new syndrome. It was only a few years later, after reporting on another two similar cases, that he isolated the famous tetrad of symptoms (finger agnosia, right-left disorientation, agraphia and acalculia) as a meaningful cluster with both localising and functional value. In this article, we provide the translation of key-excerpts of the second of Gerstmann's reports (Gerstmann, 1927) and a synoptic description of the symptoms as reported in the three original cases, which were later identified as cases of Gerstmann syndrome. The descriptions appear highly consistent across cases. Among symptoms, finger agnosia stands out for its pervasiveness, which may explain why Gerstmann considered this as the core symptom and speculated it could subtend all symptoms. However, no common functional denominator emerges from the original descriptions.

Existing theories of visual search are generally deduced from lab-based studies involving the identification of a target object among similar distractors. The role of the right parietal cortex in visual search is well-established. However, less is known about real-world visual search tasks, such as X-ray screening, which require targets to be disembedded from their background. Research has shown variations in the cognitive abilities required for these tasks and typical lab-based visual search tasks. Thus, the findings of traditional visual search studies do not always transfer into the applied domain. Although brain imaging studies have offered insights into visual search tasks involving disembedding, highlighting an association between the left parietal cortex and disembedding performance, no causal link has yet been established. To this end, we carried out a pilot study (n = 34, between-subjects) administering non-invasive brain stimulation over the posterior parietal cortex (PPC) prior to completing a security X-ray screening task. The findings suggested that anodal left PPC tDCS enhanced novice performance in X-ray screening over that of sham stimulation, in line with brain imaging findings. However, the efficacy of tDCS is under question, with a growing number of failed replications. With this in mind, this study aims to re-test our original hypothesis by examining the effects of left-side parietal stimulation on novice X-ray screener performance and comparing them to those of sham stimulation and of stimulation on a control site (right PPC). As such, this within-subjects study comprised three sessions (2 mA left PPC, 2 mA right PPC, low-intensity sham stimulation left PPC), to investigate effects of anodal tDCS on X-ray screening performance. The pre-registered analysis did not detect any significant differences between left PPC tDCS and sham tDCS or left PPC tDCS and right PPC tDCS on novice performance (d′) in X-ray screening. Further exploratory analyses detected no effects of left PPC tDCS on any other indices of performance in the X-ray security screening task (c, RTs and accuracy), or a disembedding control task (RTs and accuracy). The use of alternative stimulation techniques, with replicable behavioural effects on the parietal lobe (or a multi-technique approach), and well-powered studies with a systematic variation of stimulation parameters, could help to choose between two possible interpretations: that neither left nor right PPC are causally related to either tasks or that tDCS was ineffective. Finally, low-intensity sham stimulation (.016 mA), previously shown to outperform other sham conditions in between-subjects designs, was found to be ineffective for blinding participants in a within-subjects design. Our findings raise concerns for the current lack of optimal control conditions and add to the growing literature highlighting the need for replication in the field.

According to legislation, objects are typically classified as weapons if they are offensive per se (referred to here as proper) and if they are adapted for use as weapons or carried with the intent of causing injury (referred to here as improper), with specific regulations on their usage and possession in public spaces. However, little evidence exists on the validity of this distinction in psychology, despite a widespread recognition of the importance of psychological states and subjective perceptions in risk assessment. We conducted an online survey to evaluate hazard perceptions in relation to three dimensions (dangerousness, frequency of events, controllability) of three object categories: proper weapons, improper weapons, and everyday objects. The data from our 300 respondents reveal that the three categories of objects differ from one another on the three dimensions. Moreover, hazard perceptions differ between males and females for improper weapons but less so for proper weapons. These findings suggest that proper and improper weapons are two psychologically distinct categories, albeit with fuzzy boundaries. Investigations into their differential properties may thus help improve risk assessment in security contexts.

Sin financiación 2.990 JCR (2020) Q2, 42/140 Psychology, Multidisciplinary 0.947 SJR (2020) Q2, 68/263 Psychology (miscellaneous) No data IDR 2019 UEV

The label Gerstmann syndrome indicates the co-occurrence of four symptoms in persons with acquired brain lesions: finger agnosia, left–right disorientation, agraphia, and acalculia. The syndrome is often associated with a lesion affecting the posterior parietal lobe of the left cerebral hemisphere. Virtually every paper discussing this tetrad of symptoms refers back to Josef Gerstmann's (1924) first report published in German. To make it accessible to the wider community of scholars and thus enable a more in-depth appreciation of the origins of this enigmatic syndrome, here we publish, for the first time in English, a translation of Gerstmann's initial report. In this paper, the syndromal construct had not yet crystallized into its four cardinal symptoms; Gerstmann's attention was mainly focused on finger agnosia and, to a lesser extent, on left-right disorientation by virtue of their significance for the body scheme theory. Although isolated agraphia and acalculia seemed to be at least as severe as finger agnosia, Gerstmann did not consider them of consequential importance (with the exception of agraphia's localisation value). It is also worth noting that the described patient presented a picture of Gerstmann syndrome associated with other symptoms such as hemianopia, balance impairment, and light memory and reasoning disorders.

This chapter offers a perspective on the origin, operational definition, historic vicissitudes, and current status of Gerstmann syndrome. The main issues and controversy accompanying Gerstmann syndrome throughout the years are reviewed. The clinical picture of Gerstmann syndrome as it emerges from a series of modern-day pure cases is described. In current clinical practice, a diagnosis of Gerstmann syndrome indicates the concomitant presence of four acquired symptoms: finger agnosia, acalculia, left-right disorientation, and agraphia. Finally, based on empiric work conducted in recent years, the chapter concludes with a new interpretation of Gerstmann syndrome. If seen as an instance of intraparietal disconnection, this classic parietal syndrome will acquire fresh clinical and theoretic significance.

Here we offer a general introduction to cognitive neuroscience and provide examples relevant to psychology, healthcare and bioethics, law and criminology, information studies, of how brain studies have influenced, are influencing or show the potential to influence the social sciences. We argue that social scientists should read, and be enabled to understand, primary sources of evidence in cognitive neuroscience. We encourage cognitive neuroscientists to reflect upon the resonance that their work may have across the social sciences and to facilitate a mutually enriching interdisciplinary dialogue.

In this study we test the possible implications of high empathising skills on bodily self–other distinction by measuring the strength of a body ownership illusion and a related experience of illusory pain. One-hundred adult participants completed the Empathy Quotient (EQ) questionnaire. Twenty participants from the top quintile and 20 participants from the bottom quintile of the EQ distribution took part in a laboratory experiment. In the experiment, a classical Rubber Hand Illusion (RHI) was induced followed by the presentation of a series of painful stimuli to the rubber hand. Participants were asked to self-rate the strength of their subjective experience of the RHI and of the illusory pain. A proprioceptive location judgment on the position of the hidden hand was also required before and after RHI induction, to record drifts towards the rubber hand. We found a significant difference between high- and low-empathy participants in RHI and pain score. The EQ was not related with the proprioceptive location judgement drift. It thus appears to be a better predictor of subjective ownership feelings and phenomenological self–other merging than of the behavioural components of bodily illusions.

This chapter offers a perspective on the origin, operational definition, historic vicissitudes, and current status of Gerstmann syndrome. The main issues and controversy accompanying Gerstmann syndrome throughout the years are reviewed. The clinical picture of Gerstmann syndrome as it emerges from a series of modern-day pure cases is described. In current clinical practice, a diagnosis of Gerstmann syndrome indicates the concomitant presence of four acquired symptoms: finger agnosia, acalculia, left-right disorientation, and agraphia. Finally, based on empiric work conducted in recent years, the chapter concludes with a new interpretation of Gerstmann syndrome. If seen as an instance of intraparietal disconnection, this classic parietal syndrome will acquire fresh clinical and theoretic significance.

Studies on hacking have typically focused on motivational aspects and general personality traits of the individuals who engage in hacking; little systematic research has been conducted on predispositions that may be associated not only with the choice to pursue a hacking career but also with performance in either naïve or expert populations. Here, we test the hypotheses that two traits that are typically enhanced in autism spectrum disorders—attention to detail and systemizing—may be positively related to both the choice of pursuing a career in information security and skilled performance in a prototypical hacking task (i.e., crypto-analysis or code-breaking). A group of naïve participants and of ethical hackers completed the Autism Spectrum Quotient, including an attention to detail scale, and the Systemizing Quotient (Baron-Cohen et al., 2001, 2003). They were also tested with behavioral tasks involving code-breaking and a control task involving security X-ray image interpretation. Hackers reported significantly higher systemizing and attention to detail than non-hackers. We found a positive relation between self-reported systemizing (but not attention to detail) and code-breaking skills in both hackers and non-hackers, whereas attention to detail (but not systemizing) was related with performance in the X-ray screening task in both groups, as previously reported with naïve participants (Rusconi et al., 2015). We discuss the theoretical and translational implications of our findings.

Visual checks of thousands of X-ray images are carried out daily to detect and confiscate items that may compromise public security. Although technological advances are improving detection accuracy, screener-specific factors are also likely to matter. Here we investigated whether individual differences in self-rated attention to detail predicted performance on a simulated X-ray task with real small-vehicle images. An established measure of attention to detail was used to screen 124 naive adults; of these 29 high (n=15) and low (n=14) scoring individuals completed a detection task on unseen X-ray images. High scorers showed better performance than low scorers. The advantage emerged in both sensitivity (higher d′) and localization, with high scorers unaffected by task-irrelevant correspondence between vehicle direction and response location. These findings suggest that greater attention to detail is associated with enhanced detection ability, and that recruitment processes for security officers may be improved by assessing Attention to Detail traits.

Josef Gerstmann was first to describe patients with a selective association of finger agnosia, left–right confusion, acalculia and agraphia. Traditionally, the syndrome he introduced has been taken to indicate left parietal lobe damage, but intraoperative electrostimulation studies have failed to generate all four symptoms from a single site in the parietal cortex. On the basis of recent functional and structural neuroimaging results in healthy adults, we propose that the selective association of symptoms in pure Gerstmann’s syndrome could instead be explained by a white matter lesion at a very specific location that results in intraparietal disconnection. This result has implications for our understanding of lesion-induced cognitive dysfunction. It suggests expanding the classical concept of disconnection from disruption along a single long-distance fiber tract to situations where a conjoint disruption of separate fiber tracts determines the clinical syndrome. Such situations will arise only if a lesion affects the specific location where these separate fiber tracts happen to touch or cross each other. Given the complexity of fiber pathways in the brain, it is obvious that this mechanism can account for the huge variability in how different symptoms group together in individual patients.

Several studies showed a Simon effect when two participants sit close to each other and perform one of the two halves of a two-choice RT task. That is, each participant perform a go-nogo task. A Simon effect emerges, which instead is absent when the same go-nogo tasks are performed individually. Hence the terms were introduced of "social Simon task" and 'social Simon effect". As of now, the social Simon effect was observed with social Simon tasks that overtly gave the participants the impression of being performing in collaboration with another person. In the present study we show that the social Simon effect was present also when, in the social Simon task, the two participants did not actually collaborate. It is, however, absent when participants perform the social task outside of each other's peripersonal space (i.e., outside arm-reach). We argue that the social Simon effect does not necessarily imply a representation of the other's action, as previously suggested. The presence of an active confederate in peripersonal space might simply provide a reference for coding one's own action in space.

Healthy human brains come equipped with several circuits that contribute to number processing. Nature and nurture interact to produce a unique combination of core skills and more sophisticated abilities, by building on a handful of auxiliary routes (e.g., verbal language, body knowledge and visuospatial attention). Transcranial magnetic stimulation (TMS) studies on number processing will be here succinctly reviewed, in light of their most stimulating and challenging contributions. New research directions will be pointed out, that might enhance their theoretical impact.

Patient AM, with left visuospatial neglect, and 31 healthy participants performed a parity judgment task on numbers presented to their right parafovea. Target numbers were preceded by a pair of digits (prime) appearing peripherally for 100 ms either in their left (LVF) or in their right visual field (RVF), which participants had to ignore. In healthy participants, when primes were arithmetically related to the following target, performance was significantly slower than when primes and targets were not related. In contrast, AM's performance was slower in the related than in the control condition when prime digits appeared in his RVF, whereas it was faster in the related than in the control condition when prime digits appeared in his LVF. This suggests that neglected numbers were nevertheless processed at least until the level of stored arithmetic knowledge. Thus, visuospatial neglect does not prevent neglected numbers from accessing their representations in arithmetic networks, which seems to be a highly automatised skill. Moreover, AM's pattern of data (i.e., interference from RVF primes vs. facilitation from LVF primes) supports the hypothesis of a link between conscious attention and inhibitory processes, as proposed by Fuentes and Humphreys (1996).

Since the original description of Gerstmann's syndrome with its four cardinal symptoms, among which are finger agnosia and acalculia, the neuro-cognitive relationship between fingers and calculation has been debated. We asked our participants to perform four different tasks, two of which involved fingers and the other two involving numbers, during repetitive transcranial magnetic stimulation (rTMS) over the posterior parietal lobe of either hemisphere. In the finger tasks, they were required to transform a tactile stimulus randomly delivered on one of their fingers into a speeded key-press response either with the same or with the homologous finger on the opposite hand. In the numerical tasks, they were asked to perform a magnitude or a parity matching on pairs of single digits, in the context of arithmetically related or unrelated numerical primes. In accordance with the original anatomical hypothesis put forward by Gerstmann [Gerstmann, J. (1924). Fingeragnosie: eine umschriebene Stoerung der Orienterung am eigenen Koerper. Wiener clinische Wochenschrift, 37, 1010-12], we found that rTMS over the left angular gyrus disrupted tasks requiring access to the finger schema and number magnitude processing in the same group of participants. In addition to the numerous studies which have employed special populations such as neurological patients and children, our data confirm the presence of a relationship between numbers and body knowledge in skilled adults who no longer use their fingers for solving simple arithmetical tasks.

Three experiments tested the limiting conditions of multiplication facts retrieval in a number-matching task (LeFevre, Bisanz, & Mrkonjic, 1988). By presenting two digits as cue and by requiring participants to decide whether a subsequent numerical target had been present in the pair, we found interference when the target coincided with the product of the cue digits. This was evidence for obligatory activation of multiplication facts. Also, we showed that multiplication facts retrieval occurred even in the absence of any arithmetic context (i.e., a multiplication sign between the cue digits) and did not require processing resources (i.e., the process met the capacity criterion of automaticity; Jonides, 1981), whereas manipulation of the spatial relation between the two operands (cue digits) negatively affected retrieval. The present work appears to be unique in the context of previous similar studies on mental calculation, which invariably adopted an arithmetic task as the primary demand. We identify this difference as the reason for the failure of all previous studies in revealing independence of multiplication facts from attentional resources. Furthermore, we suggest the application of a contextual definition of automaticity to this kind of retrieval, given the fact that it might depend both on association strength and on contextual setting variables.

In three experiments, we tested the hypothesis that activation of multiplication operand nodes (e.g., 3 and 8) can occur through presentation of their product (e.g., 24). In Experiments 1 and 2 we found activation of the operands when the product was presented as a cue in a number-matching task. In Experiment 3, activation also occurred in a parity-matching task, where the product (24) was not relevant to the parity matching on its operands (3 and 8). We concluded that bidirectional links exist among the operands and their product for multiplication problems and these links can be activated in a purely stimulus-driven manner. We suggest this may constitute the basis for the solution of simple divisions by mediation through the complementary multiplication facts.

Adult observers are widely assumed to be equipped with a specific memory store containing arithmetic facts. The present study was aimed at exploring the possibility of obtaining an automatic activation of multiplication facts by using the number-matching paradigm (LeFevre, Bisanz, & Mrkonjic, 1988), in which mental arithmetic is task irrelevant. In particular, we were interested in exploring whether the nodes that precede or follow the product node in the multiplication table can also be automatically activated as a consequence of the mere presentation of two numbers. In Experiments 1 and 2, we showed that participants were slower in responding “no“ to probes that were numbers adjacent to the product in the table related to the first operand of the initial pair than to probes that were unrelated to the initial pair. In Experiments 3 and 4, we showed a similar pattern for probes that were numbers adjacent to the product in the table related to the second operand of the initial pair. Experiments 5 and 6 ruled out alternative accounts and confirmed the results of the previous experiments. Taken together the present findings suggest that multiplication facts are stored in a highly related network in which activation spreads from the product node to adjacent nodes.

In security science, efficient operation depends typically on the interaction between technology, human and machine detection and human and machine decision making. A perfect example of this interplay is ‘gatekeeping’, which is aimed to prevent the passage of people and objects that represent known threats from one end to the other end of an access point. Gatekeeping is most often achieved via visual inspections, mass screening, random sample probing and/or more targeted controls on attempted passages at points of entry. Points of entry may be physical (e.g. national borders) or virtual (e.g. connection log-ons). Who and what are defined as security threats and the resources available to gatekeepers determine the type of checks and technologies that are put in place to ensure appropriate access control. More often than not, the net performance of technology-aided screening and authentication systems ultimately depends on the characteristics of human operators. Assessing cognitive, affective, behavioural, perceptual and brain processes that may affect gatekeepers while undertaking this task is fundamental. On the other hand, assessing the same processes in those individuals who try to breach access to secure systems (e.g. hackers), and try to cheat controls (e.g. smugglers) is equally fundamental and challenging. From a security standpoint it is vital to be able to anticipate, focus on and correctly interpret the signals connected with such attempts to breach access and/or elude controls, in order to be proactive and to enact appropriate responses. Knowing cognitive, behavioral, social and neural constraints that may affect the security enterprise will undoubtedly result in a more effective deployment of existing human and technological resources. Studying how inter-observer variability, human factors and biology may affect the security agenda, and the usability of existing security technologies, is of great economic and policy interest. In addition, brain sciences may suggest the possibility of novel methods of surveillance and intelligence gathering. This is just one example of a typical security issue that may be fruitfully tackled from a neuroscientific and interdisciplinary perspective. The objective of our Research Topic was to document across relevant disciplines some of the most recent developments, ideas, methods and empirical findings that have the potential to expand our knowledge of the human factors involved in the security process. To this end we welcomed empirical contributions using different methodologies such as those applied in human cognitive neuroscience, biometrics and ethology. We also accepted original theoretical contributions, in the form of review articles, perspectives or opinion papers on this topic. The submissions brought together researchers from different backgrounds to discuss topics which have scientific, applicative and social relevance.

Security issues have been under the spotlight on a daily basis since the 9/11 terrorist attacks to the Twin Towers, which—aired on live TV—were witnessed by millions of people around the globe. This has been accompanied by the increased availability (and leakage) of security information on the Internet, the increase in public awareness over related issues, and the surge of ethical debates on the possible ethical and legal consequences of “security states”; security has taken priority in political agendas, academic debates, and research funding—the security industry is thriving. Against this background, more and more academics are exploring ways to contribute to the debate, and to inform and influence security decision making. This is both a challenging and a rewarding enterprise and neuroscience promises game-changing innovations. Security science however is a multidisciplinary field, where physics and engineering, computer science and biology, psychology and medicine, pharmacology and neuroscience, philosophy and jurisprudence, sociology and ethology can all bring valuable contributions to the table. Accordingly, in this Research Topic we have hosted relevant contributions from neuroscience and psychology experts but also dipped into other disciplines such as engineering, physics, computer science, crime science, jurisprudence, and sociology of science. We would like to thank all of the authors and the reviewers for their excellent contributions and their effort in spanning disciplinary boundaries. It is not easy to strike the right balance between expertise and accessibility, to explore a little further outside of our comfort niche and convey meaning to a multifaceted type of readership, such as the one that can be reached via open access and via Frontiers in Human Neuroscience in particular. We hope that our Research Topic will provide a useful contribution to the dialog among disciplines on security-related issues and also a successful example of how the—often artificial—disciplinary boundaries can be challenged. Almost every aspect of security is inextricably connected with technology. One of the aspects where accelerated advancements have been witnessed in recent years is the incorporation of psychological and physiological measures via new technologies. Reviews of the area of biometrics, traditionally described as the identification of individuals (or their emotional states) using physiological and behavioral characteristics, such as finger prints, iris or retinal patterns, facial features, handwriting or typing on a keyboard (see Ahmad et al., 2013), to name but a few, and the uses of sophisticated imaging techniques, such as fMRI to detect indicators of deception (see Rusconi and Mitchener-Nissen, 2013; Vartanian et al., 2013), provide two representative examples of this. The ethical and legal aspects of the use of such technologies are widespread. One the one hand, the data gathered with such technology are challenging to process and interpret, so this bears the question as to how clearly experts can present their evidence to a jury in the context of criminal justice systems; on the other hand, findings based on the use of the technology are still far from being fully reliable, research based on laboratory experiments restricts the ecological validity of such measures, and the complexity and sensitivity of the technology makes it difficult to run trials outside the laboratory or even envisage real-world applications. Another question pertains to how transparent individuals and their internal (e.g., emotional, intentional, deceptive, etc.) states can ever be made, even with a fine-grained analysis of human behavior or characteristics, as individuals become aware of advancements in technologies to assess these. Drawing on the concept of measures and countermeasures—can human suspicious behavior and intent be camouflaged so well it is not traceable by the latest neuroscientific detection systems? It is not yet clear to which extent the sophistication of technology and human perception to assess human mental and behavioral activity is juxtaposed with the sophistication of individuals to evade these security measures. Further, fully successful detection systems would have human rights, policy making and social acceptance implications, a critical issue that has been clearly recognized (see Mitchener-Nissen, 2013; Rusconi and Mitchener-Nissen, 2013). While the above methods investigate physiological or behavioral indices with technological means and algorithms, the use of human operators during incident or threat detection is still irreplaceable and critical to the security discourse (see Howard et al., 2013; Mendes et al., 2013; Stainer et al., 2013). This bears the question on how secure we actually are as both technology and humans are fallible in their decision making. It is, however, generally assumed that the output of visualization techniques such as CCTV and transmission x-rays can be appropriately assessed by trained individuals. CCTV operators are presented with large volumes of constantly updating visual information, and the navigation through this temporal and spatial data feed is very demanding. In transmission x-rays, the difficulty of complex image interpretation lies mostly in the superposition of several two-dimensional projections and the unusual views by which objects are seen in static images. To gather information about human performance in security image interpretation, diametrically opposite approaches can be adopted—from a classical hypothesis-driven experimental method to an in situ observational method reminiscent of a cognitive-ethological approach (Howard et al., 2013; Stainer et al., 2013). While technological improvements are being pursued to increase the efficiency of the screening process from an engineering and physics standpoint, these efforts may be hindered by the intrinsic limitations of the human visual perception system (see Mendes et al., 2013). Notably, to the extent that decisions are made by people, the assessment of potentially dangerous situations in a social environment is subjected to the limitations of the cognitive system that can be swayed or driven by appearances, biases, and previous experience (see Watkins, 2013; Woody and Szechtman, 2013). Of course, the same constraints will also apply to the decisions made by those individuals who actively engage in criminal activities (i.e., those who create breaches in security rather than help maintain it)—an awareness that seems yet to have been fully incorporated in evidence-based crime science (Bouhana, 2013). Brain manipulation techniques such as Transcranial Magnetic Stimulation and transcranial Direct Current Stimulation may help overcome some of the intrinsic limitations of human security operators with their potential to augment human performance in a range of tasks (Levasseur-Moreau et al., 2013; Parasuraman and Galster, 2013). Although the state of the art may not be mature enough to allow for direct translations into the security field, it is of paramount importance that neuroscientists engage as early as possible with professionals from other disciplines to formulate critical appraisals of the larger-picture implications of any of the envisaged uses (Brunelin et al., 2013; Sehm and Ragert's, 2013). Arguably, rather than hinder or slow down scientific progress, these early multidisciplinary appraisals and interactions will help secure more public support and more resources for neuroscience research.

X-ray imaging is a cost-effective technique at security checkpoints that typically require the presence of human operators. We have previously shown that self-reported attention to detail can predict threat detection performance with small-vehicle x-ray images (Rusconi et al., 2012). Here, we provide evidence for the generality of such a link by having a large sample of naïve participants screen more typical dual-energy x-ray images of hand luggage. The results show that the Attention to Detail score from the autism-spectrum quotient (AQ) questionnaire (Baron-Cohen et al., 2001) is a linear predictor of threat detection accuracy. We then develop and fine-tune a novel self-report scale for security screening: the XRIndex, which improves on the Attention to Detail scale for predictive power and opacity to interpretation. The XRIndex is not redundant with any of the Big Five personality traits. We validate the XRIndex against security x-ray images with an independent sample of untrained participants and suggest that the XRIndex may be a useful aid for the identification of suitable candidates for professional security training with a focus on x-ray threat detection. Further studies are needed to determine whether this can also apply to trained professionals.

The production of expectations or future-goals for the development of techniques which “read” and modulate brain function, represent an important practical tool for neuroscientists. These visions-of-the-future assist scientists by providing focus for both individual and cross-disciplinary research programs; they encourage the development of new industrial sectors, are used to justify the allocation of government resources and funding, and via the media can help capture the imagination and support of the public. However, such expectations need to be tempered by reality. Over-hyping brain imaging and modulation will lead to disappointment; disappointment that in turn can undermine its potential. Similarly, if neuroscientists focus their attention narrowly on the science without concomitant consideration of its future ethical, legal and social implications, then their expectations may remain unrealized. To develop these arguments herein we introduce the theoretical concept of expectations and the practical consequences of expectations. We contextualize these reflections by referring to brain imaging and modulation studies on deception, which encompass the measurement-suppression-augmentation range.

Neuropsychological studies have described patients with a selective impairment of finger identification in association with posterior parietal lesions. However, evidence of the role of these areas in finger gnosis from studies of the healthy human brain is still scarce. Here we used functional magnetic resonance imaging to identify the brain network engaged in a novel finger gnosis task, the intermanual in-between task (IIBT), in healthy participants. Several brain regions exhibited a stronger blood oxygenation level-dependent (BOLD) response in IIBT than in a control task that did not explicitly rely on finger gnosis but used identical stimuli and motor responses as the IIBT. The IIBT involved stronger signal in the left inferior parietal lobule (IPL), bilateral precuneus (PCN), bilateral premotor cortex, and left inferior frontal gyrus. In all regions, stimulation of nonhomologous fingers of the two hands elicited higher BOLD signal than stimulation of homologous fingers. Only in the left anteromedial IPL (a-mIPL) and left PCN did signal strength decrease parametrically from nonhomology, through partial homology, to total homology with stimulation delivered synchronously to the two hands. With asynchronous stimulation, the signal was stronger in the left a-mIPL than in any other region, possibly indicating retention of task-relevant information. We suggest that the left PCN may contribute a supporting visuospatial representation via its functional connection to the right PCN. The a-mIPL may instead provide the core substrate of an explicit bilateral body structure representation for the fingers that when disrupted can produce the typical symptoms of finger agnosia.

Through stimulus-response compatibility we tested whether sound frequency (pitch height) elicits a mental spatial representation. Musically untrained and, mostly, trained participants were shown a stimulus-response compatibility effect (Spatial-Musical Association of Response Codes or SMARC effect). When response alternatives were either vertically or horizontally aligned, performance was better when the lower (or leftward) button had to be pressed in response to a low sound and the upper (or rightward) button had to be pressed in response to a high sound, even when pitch height was irrelevant to the task.

Following the demise of the polygraph, supporters of assisted scientific lie detection tools have enthusiastically appropriated neuroimaging technologies “as the savior of scientifically verifiable lie detection in the courtroom” (Gerard, 2008: 5). These proponents believe the future impact of neuroscience “will be inevitable, dramatic, and will fundamentally alter the way the law does business” (Erickson, 2010: 29); however, such enthusiasm may prove premature. For in nearly every article published by independent researchers in peer reviewed journals, the respective authors acknowledge that fMRI research, processes, and technology are insufficiently developed and understood for gatekeepers to even consider introducing these neuroimaging measures into criminal courts as they stand today for the purpose of determining the veracity of statements made. Regardless of how favorable their analyses of fMRI or its future potential, they all acknowledge the presence of issues yet to be resolved. Even assuming a future where these issues are resolved and an appropriate fMRI lie-detection process is developed, its integration into criminal trials is not assured for the very success of such a future system may necessitate its exclusion from courtrooms on the basis of existing legal and ethical prohibitions. In this piece, aimed for a multidisciplinary readership, we seek to highlight and bring together the multitude of hurdles which would need to be successfully overcome before fMRI can (if ever) be a viable applied lie detection system. We argue that the current status of fMRI studies on lie detection meets neither basic legal nor scientific standards. We identify four general classes of hurdles (scientific, legal and ethical, operational, and social) and provide an overview on the stages and operations involved in fMRI studies, as well as the difficulties of translating these laboratory protocols into a practical criminal justice environment. It is our overall conclusion that fMRI is unlikely to constitute a viable lie detector for criminal courts.

Considering the variety and scope of actions we perform together with others, it would seem unlikely that the entire range of joint actions can be exhaustively clarified by invoking a single mechanism. Guagnano et al. (2010) extended the field of joint actions by reporting a joint Simon effect with people carrying out separate assignments in adjacent locations, rather than with confederates collaborating to an assignment. In addition, they proposed that the space where two people act (peripersonal vs. extrapersonal) does matter in such a context. Here we comment on the inaccuracies in the theoretical, factual and methodological representation that Welsh et al. (2013) provide of Guagnano et al. (2010).

Neuropsychological, neurophysiological, and neuroimaging studies suggest that right frontoparietal circuits may be necessary for the processing of mental number space, also known as the mental number line (MNL). Here we sought to specify the critical time course of three nodes that have previously been related to MNL processing: right posterior parietal cortex (rPPC), right FEF (rFEF), and right inferior frontal gyrus (rIFG). The effects of single-pulse TMS delivered at 120% distance-adjusted individual motor threshold were investigated in 21 participants, within a window of 0–400 msec (sampling interval = 33 msec) from the onset of a central digit (1–9, 5 excluded). Pulses were delivered in a random order and with equal probability at each time point, intermixed with noTMS trials. To analyze whether and when TMS interfered with MNL processing, we fitted bimodal Gaussian functions to the observed data and measured effects on changes in the Spatial–Numerical Association of Response Codes (SNARC) effect (i.e., an advantage for left- over right-key responses to small numbers and right- over left-key responses to large numbers) and in overall performance efficiency. We found that, during magnitude judgment with unimanual key-press responses, TMS reduced the SNARC effect in the earlier period of the fitted functions (∼25–60 msec) when delivered over rFEF (small and large numbers) and rIFG (small numbers); TMS further reduced the SNARC effect for small numbers in a later period when delivered to rFEF (∼200 msec). In contrast, TMS of rPPC did not interfere with the SNARC effect but generally reduced performance for small numbers and enhanced it for large numbers, thus producing a pattern reminiscent of “neglect” in mental number space. Our results confirm the causal role of an intact right frontoparietal network in the processing of mental number space. They also indicate that rPPC is specifically tied to explicit number magnitude processing and that rFEF and rIFG contribute to interfacing mental visuospatial codes with lateralized response codes. Overall, our findings suggest that both ventral and dorsal frontoparietal circuits are causally involved and functionally connected in the mapping of numbers to space.

© Oxford University Press, 2008. All rights reserved. This article introduces the relationship between mathematical cognition and transcranial magnetic stimulation (TMS). The mental number line is located in the parietal lobe. Studies employing TMS have explored issues related to the mental number line. This article reviews the studies centered on the magnitude code. The results show that even though the parietal activation is nearly always present in both hemispheres, it is often asymmetric, being greater in the right hemisphere when quantification of nonverbal and nonsymbolic material is required. Neuropsychological studies confirm the relation between the magnitude code and the parietal lobe. The extent to which number-related processes are number specific, and the extent to which they overlap with other aspects of spatial or magnitude representation, is currently a burgeoning area of research. Current work is aimed to disrupt numerical processes and observe concomitant changes in brain activation.

Congenital amusia is a lifelong disorder of music processing that has been ascribed to impaired pitch perception and memory. The present study tested a large group of amusics (n = 17) and provided evidence that their pitch deficit affects pitch processing in speech to a lesser extent: Fine-grained pitch discrimination was better in spoken syllables than in acoustically matched tones. Unlike amusics, control participants performed fine-grained pitch discrimination better for musical material than for verbal material. These findings suggest that pitch extraction can be influenced by the nature of the material (music vs speech), and that amusics’ pitch deficit is not restricted to musical material, but extends to segmented speech events.

That disconnection causes clinical symptoms is a very influential concept in behavioral neurology. Criteria for subcortical disconnection usually are symptoms that are distinct from those following cortical lesions and damage to a single, long-range fiber tract. Yet, a recent study combining functional magnetic resonance imaging and fiber tracking concluded that a focal lesion in left parietal white matter provides the only tenable explanation for pure Gerstmann’s syndrome, an enigmatic tetrad of acalculia, agraphia, finger agnosia, and left-right disorientation. Such a lesion would affect not only a single fiber tract but crossing or “kissing” of different fiber tracts and hence disconnect separate cortical networks. As fiber crossing is prominent in the cerebral white matter, the authors propose an extension to the subcortical disconnection framework that opens the door to ascribing a more diversified clinical phenomenology to white matter damage and ensuing disconnection than has been the case so far.

A structural representation of the hand embedding information about the identity and relative position of fingers is necessary to counting routines. It may also support associations between numbers and allocentric spatial codes that predictably interact with other known numerical spatial representations, such as the mental number line (MNL). In this study, 48 Western participants whose typical counting routine proceeded from thumb-to-little on both hands performed magnitude and parity binary judgments. Response keys were pressed either with the right index and middle fingers or with the left index and middle fingers in separate blocks. 24 participants responded with either hands in prone posture (i.e., palm down) and 24 participants responded with either hands in supine (i.e., palm up) posture. When hands were in prone posture, the counting direction of the left hand conflicted with the direction of the left–right MNL, whereas the counting direction of the right hand was consistent with it. When hands were in supine posture, the opposite was true. If systematic associations existed between relative number magnitude and an allocentric spatial representation of the finger series within each hand, as predicted on the basis of counting habits, interactions would be expected between hand posture and a unimanual version of the spatial–numerical association of response codes (SNARC) effect. Data revealed that with hands in prone posture a unimanual SNARC effect was present for the right hand, and with hands in supine posture a unimanual SNARC effect was present for the left hand. We propose that a posture-invariant body structural representation of the finger series provides a relevant frame of reference, a within-hand directional vector, that is associated to simple number processing. Such frame of reference can significantly interact with stimulus–response correspondence effects, like the SNARC, that have been typically attributed to the mapping of numbers on a left-to-right mental line.

Neuropsychological and neurophysiological studies have suggested that prefrontal cortex may be involved in non-verbal number processing, when relevant for current behavioural goals. More precisely, it has been suggested that an intact right inferior frontal gyrus (rIFG) in humans may be necessary to the use of a spatial representation of numbers, also known as mental number line. In a popular model of spatial functions (e.g., Corbetta et al., 2008), rIFG is part of a right-lateralised ventral fronto-parietal network that conveys signals to a dorsal network supporting attentional orienting in contralateral space. Within the dorsal network, the frontal eye fields (FEF) are known to contribute to visual scene analysis and visual conjunction search tasks when eye movement commands are not required. In the present study, we hypothesised they might also be involved in exploring a conceptual space, such as the mental number line. We examined the proposed functions of the human rIFG and right Frontal Eye Field (rFEF) by interfering with their normal functioning with repetitive Transcranial Magnetic Stimulation (rTMS) while participants performed numerical tasks. The results suggest that, when number magnitude is relevant to the task, rIFG supports orienting to the entire mental number line while rFEF are crucial for contralateral orienting (that is towards small numbers).