Markus Werning

Minds, persons, and space: An fMRI investigation into the relational complexity of higher-order intentionality

Mental state reasoning or theory-of-mind has been the subject of a rich body of imaging research. Although such investigations routinely tap a common set of regions, the precise function of each area remains a contentious matter. With the help of functional magnetic resonance imaging (fMRI), we sought to determine which areas are involved when processing mental state or intentional metarepresentations by focusing on the relational aspect of such representations. Using non-intentional relational representations such as spatial relations between persons and between objects as a contrast, the results ascertained the involvement of the precuneus, the temporal poles, and the medial prefrontal cortex in the processing of intentional representations. In contrast, the anterior superior temporal sulcus and the left temporo-parietal junction were implicated when processing representations that refer to the presence of persons in relational contexts in general. The right temporo-parietal junction, however, was specifically activated for persons entering spatial relations. The level of representational complexity, a previously unexplored factor, was also found to modulate the neural response in some brain regions, such as the medial prefrontal cortex and the right temporo-parietal junction. These findings highlight the need to take into account the critical roles played by an extensive network of neural regions during mental state reasoning.

Matching mind to world and vice versa: Functional dissociations between belief and desire mental state processing

Abstract With the aim of understanding how different mental or intentional states are processed in the brain, the present functional magnetic resonance imaging (fMRI) study examined the brain correlates during the ascription of belief intentional states relative to desire intentional states as well as the effect of incongruent relative to congruent intentional states. To this end, sentences containing scenarios were presented to participants and their task was to make judgments concerning the ascription of intentional states based on this information. Belief ascriptions, relative to desire ascriptions, were accompanied by activations in lateral prefrontal structures that include areas known to be involved in relational and conceptual reasoning. Desire ascriptions, in contrast, were accompanied by activations in regions of the medial prefrontal cortex, superior temporal gyri and hippocampal formation, all of which are known for their involvement in self-referential, autobiographical and episodic memory-relevant processes. In addition, the ascription of intentional states that were incongruent with reality (false beliefs and unfulfilled desires) was compared to the ascription of intentional states that were congruent to reality (true belief and fulfilled desires). While no brain region was selectively activated during the processing of unfulfilled desires, the processing of false beliefs was associated with stronger activations in the dorsal medial prefrontal cortex, an area that has been previously linked to the process of decoupling in false belief attribution. These findings provide new insights into more fine-grained aspects of mental state reasoning.

THE TEMPORAL DIMENSION OF THOUGHT Cortical Foundations of Predicative Representation

The paper argues that cognitive states of biological systems are inherently temporal. Three adequacy conditions for neuronal models of representation are vindicated: the compositionality of meaning, the compositionality of content, and the co-variation with content. Classicist and connectionist approaches are discussed and rejected. Based on recent neurobiological data, oscillatory networks are introduced as a third alternative. A mathematical description in a Hilbert space framework is developed. The states of this structure can be regarded as conceptual representations satisfying the three conditions.

Synesthesia, Sensory-Motor Contingency, and Semantic Emulation: How Swimming Style-Color Synesthesia Challenges the Traditional View of Synesthesia

Synesthesia is traditionally regarded as a phenomenon in which an additional non-standard phenomenal experience occurs consistently in response to ordinary stimulation applied to the same or another modality. Recent studies suggest an important role of semantic representations in the induction of synesthesia. In the present proposal we try to link the empirically grounded theory of sensory-motor contingency and mirror system based embodied simulation/emulation to newly discovered cases of swimming style-color synesthesia. In the latter color experiences are evoked only by showing the synesthetes a picture of a swimming person or asking them to think about a given swimming style. Neural mechanisms of mirror systems seem to be involved here. It has been shown that for mirror-sensory synesthesia, such as mirror-touch or mirror-pain synesthesia (when visually presented tactile or noxious stimulation of others results in the projection of the tactile or pain experience onto oneself), concurrent experiences are caused by overactivity in the mirror neuron system responding to the specific observation. The comparison of different forms of synesthesia has the potential of challenging conventional thinking on this phenomenon and providing a more general, sensory-motor account of synesthesia encompassing cases driven by semantic or emulational rather than pure sensory or motor representations. Such an interpretation could include top-down associations, questioning the explanation in terms of hard-wired structural connectivity. In the paper the hypothesis is developed that the wide-ranging phenomenon of synesthesia might result from a process of hyperbinding between “too many” semantic attribute domains. This hypothesis is supplemented by some suggestions for an underlying neural mechanism.

What is episodic memory if it is a natural kind

Colloquially, episodic memory is described as “the memory of personally experienced events”. Even though episodic memory has been studied in psychology and neuroscience for about six decades, there is still great uncertainty as to what episodic memory is. Here we ask how episodic memory should be characterized in order to be validated as a natural kind. We propose to conceive of episodic memory as a knowledge-like state that is identified with an experientially based mnemonic representation of an episode that allows for a mnemonic simulation thereof. We call our analysis the Sequence Analysis of Episodic Memory since episodes will be analyzed in terms of sequences of events. Our philosophical analysis of episodic memory is driven and supported by experimental results from psychology and neuroscience. We discuss selected experimental results that provide exemplary evidence for uniform causal mechanisms underlying the properties of episodic memory and argue that episodic memory is a natural kind. The argumentation proceeds along three cornerstones: First, psychological evidence suggests that a violation of any of the proposed conditions for episodic memory amounts to a deficiency of episodic memory and no form of memory or cognitive process but episodic memory fulfills them. Second, empirical results support a claim that the principal anatomical substrate of episodic memory is the hippocampus. Finally, we can pin down causal mechanisms onto neural activities in the hippocampus to explain the psychological states and processes constituting episodic memory.

Dissociating memory traces and scenario construction in mental time travel

There has been a persistent debate about how to define episodic memory and whether it is a uniquely human capacity. On the one hand, many animal cognition studies employ content-based criteria, such as the what-where-when criterion, and argue that nonhuman animals possess episodic memory. On the other hand, many human cognition studies emphasize the subjective experience during retrieval as an essential property of episodic memory and the distinctly human foresight it purportedly enables. We propose that both perspectives may examine distinct but complementary aspects of episodic memory by drawing a conceptual distinction between episodic memory traces and mental time travel. Episodic memory traces are sequential mnemonic representations of particular, personally experienced episodes. Mental time travel draws on these traces, but requires other components to construct scenarios and embed them into larger narratives. Various nonhuman animals may store episodic memory traces, and yet it is possible that only humans are able to construct and reflect on narratives of their lives - and flexibly compare alternative scenarios of the remote future.

Temporal binding of non-uniform objects

Abstract Gestalt-based feature binding becomes problematic if different objects overlap in their positional configuration and/or feature space, or if features vary over the spatial extent of an object. If synchronization is to be a viable mechanism for binding the responses of disparate feature selective neurons in the brain, it must cope with resulting ambiguities. In this article the synchronization properties of an oscillator network for multidimensional feature binding are investigated. For non-uniform feature distributions in a stimulus, its components are adequately represented by the eigenmodes of the oscillatory dynamics. The significance of the eigenmodes corresponds to the salience of different stimulus interpretations.

Conceptual Fingerprints: Lexical Decomposition by Means of Frames --- a Neuro-cognitive Model

Frames, i.e., recursive attribute-value structures, are a general format for the decomposition of lexical concepts. Attributes assign unique values to objects and thus describe functional relations. Concepts can be classified into four groups: sortal, individual, relational and functional concepts. The classification is reflected by different grammatical roles of the corresponding nouns. The paper aims at a cognitively adequate decomposition, particularly, of sortal concepts by means of frames. Using typed feature structures, an explicit formalism for the characterization of cognitive frames is developed. The frame model can be extended to account for typicality effects. Applying the paradigm of object-related neural synchronization, furthermore, a biologically motivated model for the cortical implementation of frames is developed. Cortically distributed synchronization patterns may be regarded as the fingerprints of concepts.

Synchrony and Composition: Toward a Cognitive Architecture between Classicism and Connectionism

Using the tools of universal algebra, it is shown that oscillatory networks realize systematic cognitive representations. It is argued (i) that an algebra of propositions and concepts for objects and properties is isomorphic to an algebra of brain states, neuronal oscillations and sets of oscillations related to clusters of neurons, (ii) that the isomorphism, in a strong sense, preserves the constituent relations of the conceptual algebra, and (iii) that the isomorphism transfers semantic compositionality. Oscillatory networks are neurobiologically plausible. They combine the virtues and avoid the vices of classical and connectionist architectures.

Descartes discarded? Introspective self-awareness and the problems of transparency and compositionality ☆

What has the self to be like such that introspective awareness of it is possible? The paper asks if Descartess idea of an inner self can be upheld and discusses this issue by invoking two principles: the phenomenal transparency of experience and the semantic compositionality of conceptual content. It is assumed that self-awareness is a second-order state either in the domain of experience or in the domain of thought. In the former case self-awareness turns out empty if experience is transparent. In the latter, it can best be conceived of as a form of mental quotation. Various proposed analyses of direct and indirect quotation are discussed and tested regarding their applicability to thought. It is concluded that, on the assumption of compositionality, the inner self is only insofar accessible to awareness as it has an accessible phonological (or otherwise subsymbolic) structure, as apparently only inner speech does.