Probabilistic and deductive reasoning in the human brain.

Reasoning is a process of inference from given premises to new conclusions. Deductive reasoning is truth-preserving and conclusions can only be either true or false. Probabilistic reasoning is based on degrees of belief and conclusions can be more or less likely. While deductive reasoning requires people to focus on the logical structure of the inference and ignore its content, probabilistic reasoning requires the retrieval of prior knowledge from memory. Recently, however, some researchers have denied that deductive reasoning is a faculty of the human mind. What looks like deductive inference might actually also be probabilistic inference, only with extreme probabilities. We tested this assumption in an fMRI experiment with two groups of participants: one group was instructed to reason deductively, the other received probabilistic instructions. They could freely choose between a binary and a graded response to each problem. The conditional probability and the logical validity of the inferences were systematically varied. Results show that prior knowledge was only used in the probabilistic reasoning group. These participants gave graded responses more often than those in the deductive reasoning group and their reasoning was accompanied by activations in the hippocampus. Participants in the deductive group mostly gave binary responses and their reasoning was accompanied by activations in the anterior cingulate cortex, inferior frontal cortex, and parietal regions. These findings show that (1) deductive and probabilistic reasoning rely on different neurocognitive processes, (2) people can suppress their prior knowledge to reason deductively, and (3) not all inferences can be reduced to probabilistic reasoning.

Specificity effects in reasoning with counterintuitive and arbitrary conditionals.

When people have prior knowledge about an inference, they accept conclusions from specific conditionals (e.g., "If Jack does sports, then Jack loses weight") more strongly than for unspecific conditionals (e.g., "If a person does sports, then the person loses weight"). But can specific phrasings also elevate the acceptance of conclusions from unbelievable conditionals? In Experiment 1, we varied the specificity of counterintuitive conditionals, which described the opposite of what is expected according to everyday experiences ("If Lena/a person studies hard, then Lena/the person will not do well on the test"). In Experiment 2, we varied the specificity of arbitrary conditionals, which had no obvious link between antecedent and consequent ("If Mary/a person goes shopping, then Mary/ the person gets pimples"). All conditionals were embedded in MP and AC inferences. Participants were instructed to reason as in daily life and to evaluate the conclusions on a 7-point Likert scale. Our results showed a specificity effect in both experiments: participants gave higher acceptance ratings for specific than for unspecific conditionals.

Different cognitive styles can affect performance in laparoscopic surgery skill training.

BACKGROUND: The lack of depth cues and haptic feedback makes minimally invasive surgery a cognitive challenge. It is therefore important to know which individuals are expected to perform well in minimally invasive surgery. In cognitive psychology, methods are available with which one can measure different cognitive thinking styles. It is well known that these cognitive styles correlate with many different tasks. We investigated whether this method can also predict performance on a box trainer (Lübeck Toolbox®), a device for training laparoscopic surgery. If so, the method might help to select and train those people who will most likely develop high skills in minimally invasive surgery. METHODS: Thirty medical students and thirty non-medical students performed five laparoscopic surgical tasks on a box trainer. We measured the time required and the errors participants made on each task. Their cognitive style was measured with a method from cognitive psychology that distinguishes between people who think visually, spatially, or verbally. Furthermore, all students completed a subset of a standard intelligence test (Wechsler Adult Intelligence Scale) and three subtests of the German Medical University Admission Test (TMS). RESULTS: Participants with spatial thinking styles performed best on the box trainer. Visual and verbal cognitive styles impeded box trainer performance. Performance on the box trainer could also be predicted by the TMS and IQ scores. CONCLUSIONS: The study shows for the first time that a standard method from cognitive psychology can be used to distinguish between different cognitive styles in surgical education and that these different cognitive styles affect performance on a box trainer. Since the correlation between box trainer performance and surgical proficiency is well documented, the method might be an efficient way to reduce errors and to elevate patient safety in laparoscopic surgery.

TMS applied to V1 can facilitate reasoning.

Visual mental imagery is the subjective experience of seeing objects or events in front of the 'inner eye', although they are not actually present. Previous research indicates that (1) visual images help to remember what has been experienced in the past or when objects need to be inspected or manipulated, and (2) visual images are correlated with neural activity in early visual cortices, demonstrating a possible overlap between visual imagery and visual perception. However, recent research revealed that visual imagery can also disrupt cognitive processes and impede thinking. In this transcranial magnetic stimulation (TMS) experiment, participants had to solve relational reasoning problems that varied in their imageability (easy or difficult to visualize as a mental image). While solving the problems, eight 10 Hz pulses were either applied to primary visual cortex (V1) or a control site (Vertex). Our findings suggest a causal link between mental imagery, primary visual cortex, and reasoning with visual problems. Moreover, participants exhibited much lower error rates when TMS was applied to V1. We conclude that the disruption of visual images in primary visual cortex can facilitate reasoning.

Uncertain relational reasoning in the parietal cortex.

The psychology of reasoning is currently transitioning from the study of deductive inferences under certainty to inferences that have degrees of uncertainty in both their premises and conclusions; however, only a few studies have explored the cortical basis of uncertain reasoning. Using transcranial magnetic stimulation (TMS), we show that areas in the right superior parietal lobe (rSPL) are necessary for solving spatial relational reasoning problems under conditions of uncertainty. Twenty-four participants had to decide whether a single presented order of objects agreed with a given set of indeterminate premises that could be interpreted in more than one way. During the presentation of the order, 10-Hz TMS was applied over the rSPL or a sham control site. Right SPL TMS during the inference phase disrupted performance in uncertain relational reasoning. Moreover, we found differences in the error rates between preferred mental models, alternative models, and inconsistent models. Our results suggest that different mechanisms are involved when people reason spatially and evaluate different kinds of uncertain conclusions.

Defeasible reasoning with legal conditionals.

Valid conclusions can be defeated if people can think of conditions that prevent the consequent to occur although the antecedent is given. The goal of the present research was to investigate how people consider these conditions when reasoning with legal conditionals such as "If a person kills another human, then this person should be punished for manslaughter." In Experiments 1 and 2 legal conditionals were presented to participants together with exculpatory circumstances, i.e., counterexamples. The participants' task was to decide whether they would adhere to the legal conditional rule and punish the offender. Participants were either lawyers (i.e., advanced law students and graduate lawyers) or legal laypeople. We found that laypeople often ignore exculpatory circumstances and adhere to the conditional rule when offences evoked high levels of moral outrage. Lawyers did not show this effect. In Experiment 3 laypeople showed difficulties even when asked to simply imagine exculpatory circumstances for highly morally outrageous offences. Results provide new evidence for the role of emotions--like moral outrage--in the consideration of counterexamples to legal conditionals.

The Giessen virtual environment laboratory: human wayfinding and landmark salience.

In our virtual environment laboratory, we focus on different topics in human spatial cognition with projects on landmark salience, route knowledge, and survey knowledge. Within this laboratory note, we provide an overview of previous, current, and future work with our virtual environment SQUARELAND.

Editors' Review and Introduction: Levels of Explanation in Cognitive Science: From Molecules to Culture.

Cognitive science began as a multidisciplinary endeavor to understand how the mind works. Since the beginning, cognitive scientists have been asking questions about the right methodologies and levels of explanation to pursue this goal, and make cognitive science a coherent science of the mind. Key questions include: Is there a privileged level of explanation in cognitive science? How do different levels of explanation fit together, or relate to one another? How should explanations at one level inform or constrain explanations at some other level? Can the different approaches to the mind, brain, and culture be unified? The aim of this issue of topiCS is to provide a platform for discussing different answers to such questions and to facilitate a better understanding between the different strands of thinking about the right levels of explanation in cognitive science.

Odors Can Serve as Landmarks in Human Wayfinding.

Scientists have shown that many non-human animals such as ants, dogs, or rats are very good at using smells to find their way through their environments. But are humans also capable of navigating through their environment based on olfactory cues? There is not much research on this topic, a gap that the present research seeks to bridge. We here provide one of the first empirical studies investigating the possibility of using olfactory cues as landmarks in human wayfinding. Forty subjects participated in a piloting study to determine the olfactory material for the main experiment. Then, 24 subjects completed a wayfinding experiment with 12 odors as orientation cues. Our results are astonishing: Participants were rather good at what we call "odor-based wayfinding." This indicates that the ability of humans to use olfactory cues for navigation is often underestimated. We discuss two different cognitive explanations and rule out the idea that our results are just an instance of sequential learning. Rather, we argue that humans can enrich their cognitive map of the environment with olfactory landmarks and may use them for wayfinding.

How to infer possibilities: A reply to Oaksford et al. (2018).

Individuals draw conclusions about possibilities from assertions that make no explicit reference to them. The model theory postulates that assertions such as disjunctions refer to possibilities. Hence, a disjunction of the sort, A or B or both, where A and B are sensible clauses, yields mental models of an exhaustive conjunction of possibly A, possibly B, and possibly both A and B, which each hold in default of information to the contrary. Oaksford, Over, and Cruz (this issue) are critical of the model theory and defend a probabilistic approach to reasoning. In this reply, we deal with their three main claims: (a) Our results concern only the periphery of their probabilistic theory. We show that they refute their theory insofar as it applies to possibilities. (b) The model theory leads to logical absurdities. We rebut this criticism as it applies to the model theory in Hinterecker, Knauff, and Johnson-Laird (2016), and explain why standard modal logics, which concern possibilities, do not set appropriate norms for inferences about them. (c) The algorithm for reasoning based on models needs a normative theory. In fact, it has such a theory, but the demand for "a specification of a sound, complete, and decidable normative system" is chimerical for everyday reasoning. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Working memory in wayfinding-a dual task experiment in a virtual city.

This study examines the working memory systems involved in human wayfinding. In the learning phase, 24 participants learned two routes in a novel photorealistic virtual environment displayed on a 220° screen while they were disrupted by a visual, a spatial, a verbal, or-in a control group-no secondary task. In the following wayfinding phase, the participants had to find and to "virtually walk" the two routes again. During this wayfinding phase, a number of dependent measures were recorded. This research shows that encoding wayfinding knowledge interfered with the verbal and with the spatial secondary task. These interferences were even stronger than the interference of wayfinding knowledge with the visual secondary task. These findings are consistent with a dual-coding approach of wayfinding knowledge.

When will is not the same as should: The role of modals in reasoning with legal conditionals.

Naïve reasoners reject logically valid conclusions from conditional rules if they can think of exceptions in which the antecedent is true, but the consequent is not. However, when reasoning with legal conditionals (e.g., "If a person kills another human, then this person should be punished for manslaughter") people hardly consider exceptions but evaluate conclusions depending on their own sense of justice. We show that participants' reluctance to consider exceptions in legal reasoning depends on the modal auxiliary used. In two experiments we phrased legal conditionals either with the modal "should" (i.e., " . . . then this person should be punished"), or with "will" (i.e., " . . . then this person will be punished") and presented them as modus ponens or modus tollens inferences. Participants had to decide whether the offender should or will be punished (modus ponens) or whether the offender indeed committed the offence (modus tollens). For modus ponens inferences phrased with "should" we replicate previous findings showing that participants select conclusions on the basis of their own sense of justice (Experiments 1 and 2). Yet, when the legal conditional is phrased with the modal "will" this effect is attenuated (Experiments 1 and 2), and exceptions are considered (Experiment 1). The modal auxiliary did not affect modus tollens inferences.

Modality, probability, and mental models.

We report 3 experiments investigating novel sorts of inference, such as: A or B or both. Therefore, possibly (A and B). Where the contents were sensible assertions, for example, Space tourism will achieve widespread popularity in the next 50 years or advances in material science will lead to the development of antigravity materials in the next 50 years, or both. Most participants accepted the inferences as valid, though they are invalid in modal logic and in probabilistic logic too. But, the theory of mental models predicts that individuals should accept them. In contrast, inferences of this sort­A or B but not both. Therefore, A or B or both­are both logically valid and probabilistically valid. Yet, as the model theory also predicts, most reasoners rejected them. The participants' estimates of probabilities showed that their inferences tended not to be based on probabilistic validity, but that they did rate acceptable conclusions as more probable than unacceptable conclusions. We discuss the implications of the results for current theories of reasoning.

Correction:An Efficiency Comparison of Document Preparation Systems Used in Academic Research and Development.

This article was republished on March 30, 2015, to correct the sizing and placement of thefigures; none of the article content was changed. The publisher apologizes for the originallayout errors. Please download this article again to view the corrected version. The originallypublished, uncorrected article and the republished, corrected article are provided herefor reference.

The construction of spatial mental models-A new view on the continuity effect.

Many studies show that spatial reasoning with information that describe relations between two or more objects relies on the construction and inspection of mental models. This article mainly focuses on the phenomenon that humans have more difficulties in processing spatial information that is not directly related to each other-for example, presented discontinuously-what is also known as the continuity effect. The article investigates how humans integrate such information into one unified mental model. In four experiments, we investigated the question whether (a) reasoners construct more than one (preliminary) model, with the first two premises presented in a discontinuous description, and integrate the models afterwards, or alternatively (b) construct one preliminary model that is later modified in the light of the last parts of problem description. The results support the second assumption and offer a new view on the continuity effect and the fundamental principles of model construction and variation in human spatial reasoning.

Grounded spatial belief revision.

Beliefs frequently undergo revisions, especially when new pieces of information are true but inconsistent with current beliefs. In previous studies, we showed that linguistic asymmetries provided by relational statements, play a crucial role in spatial belief revision. Located objects (LO) are preferably revised compared to reference objects (RO), known as the LO-principle. Here we establish a connection between spatial belief revision and grounded cognition. In three experiments, we explored whether imagined physical object properties influence which object is relocated and which remains at its initial position. Participants mentally revised beliefs about the arrangements of objects which could be envisaged as light and heavy (Experiment 1), small and large (Experiment 2), or movable and immovable (Experiment 3). The results show that intrinsic object properties are differently taken into account during spatial belief revision. Object weight did not alter the LO-principle (Experiment 1), whereas object size was found to influence which object was preferably relocated (Experiment 2). Object movability did not affect relocation preferences but had an effect on relocation durations (Experiment 3). The findings support the simulation hypothesis within the grounded cognition approach and create new connections between the spatial mental model theory of reasoning and the idea of grounded cognition.

Reasoning and working memory: common and distinct neuronal processes.

The neuronal processes underlying reasoning and the related working memory subsystems were examined with functional magnetic resonance imaging (fMRI). Twelve volunteers solved relational reasoning problems which either supported a single (determinate) or several alternative solutions (indeterminate). In a second condition, participants maintained the identical premises of these problems in working memory without making inferences. Although problems were presented in auditory format, activity was detected for both reasoning and maintenance in a network comprising bilaterally the secondary visual cortex, the posterior cingulate cortex, and the medial anterior frontal cortex. In direct comparisons, reasoning was associated with stronger dorsolateral and medial prefrontal activation than maintenance, whereas maintenance led to stronger lateral parietal activation than reasoning. Participants' visuo-spatial abilities ("Block Design" score) covaried positively with behavioral performance and negatively with activity of the precuneus for reasoning, but not for maintenance. These results support the notion that relational reasoning is based on visuo-spatial mental models, and they help to distinguish the neuronal processes related to reasoning itself versus to the maintenance of problem information in working memory.

Spatial imagery in deductive reasoning: a functional MRI study.

Various cognitive theories aim to explain human deductive reasoning: (1) mental logic theories claim syntactic language-based proofs of derivation, (2) the mental model theory proposes cognitive processes of constructing and manipulating spatially organized mental models, and (3) imagery theories postulate that such abilities are based on visual mental images. To explore the neural substrates of human deductive reasoning, we examined BOLD (blood oxygen level dependent) contrasts of twelve healthy participants during relational and conditional reasoning with whole-brain functional magnetic resonance imaging (fMRI). The results indicate that, in the absence of any correlated visual input, reasoning activated an occipitoparietal-frontal network, including parts of the prefrontal cortex (Brodmann's area, BA, 6, 9) and the cingulate gyrus (BA 32), the superior and inferior parietal cortex (BA 7, 40), the precuneus (BA 7), and the visual association cortex (BA 19). In the discussion, we first focus on the activated occipito-parietal pathway that is well known to be involved in spatial perception and spatial working memory. Second, we briefly relate the activation in the prefrontal cortical areas and in the anterior cingulate gyrus to other imaging studies on higher cognitive functions. Finally, we draw some general conclusions and argue that reasoners envisage and inspect spatially organized mental models to solve deductive inference problems.

An efficiency comparison of document preparation systems used in academic research and development.

The choice of an efficient document preparation system is an important decision for any academic researcher. To assist the research community, we report a software usability study in which 40 researchers across different disciplines prepared scholarly texts with either Microsoft Word or LaTeX. The probe texts included simple continuous text, text with tables and subheadings, and complex text with several mathematical equations. We show that LaTeX users were slower than Word users, wrote less text in the same amount of time, and produced more typesetting, orthographical, grammatical, and formatting errors. On most measures, expert LaTeX users performed even worse than novice Word users. LaTeX users, however, more often report enjoying using their respective software. We conclude that even experienced LaTeX users may suffer a loss in productivity when LaTeX is used, relative to other document preparation systems. Individuals, institutions, and journals should carefully consider the ramifications of this finding when choosing document preparation strategies, or requiring them of authors.