Projects

Neural Basis of Action Planning and Action Selection

To isolate the brain processes that underlie the selection and generation of goal directed behavior we resort to functional magnetic resonance imaging (fMRI) during delayed response tasks (see figure). These tasks allow temporally separating planning and decision processes during a "Delay" from representations of both the sensory context they depend on ("Instruction") and the motor acts they ultimately produce ("Response"). Using such task design we show at the level of human posterior parietal and premotor cortex and plans for upcoming finger reaches are encoded (Lindner et al., 2010). These plans are formed in a way that (also) considers the visual consequences of the movement (Pilacinski et al., 2018) as well as information about movement trajectories (Pilacinski & Lindner, 2019). Notably, up to a certain limit, our brain can represent multiple concurrent plans thereby warranting optimal behavioral performance (Schach et al., 2022). Given that such planning activity in posterior parietal and premotor cortex is additionally modulated by decision variables such as reward and punishment (Iyer et al., 2010), makes these areas interesting candidates for the neural monitoring of action selection (e.g. in order to inform brain machine interfaces, etc.).

Ongoing Research on Action Planning and Action Selection

  • Cross-hemispheric recruitment during action planning with increasing task demand. In collaboration with Sonja Schach & Prof. Dr. Dr. Daniel Alexander Braun, University of Ulm, Ulm, Germany. [manuscript available]. We have previously shown that a co-recruitment of functionally homolog areas in the non-dominant hemisphere of prefrontal cortex support the maintenance of retrospective information in working memory (compare Höller-Wallscheid et al., 2017; also see our research on Working Memory and Cognitive Aging). Is such “cross-hemispheric recruitment” also in other brain regions and does it also support prospective action planning?

  • Do movement trajectories reflect an integrated plan of where to reach and what to avoid? Lorena Witzl. In our previous fMRI research we suggest that posterior parietal and premotor cortex plan where to reach and what to avoid (Lindner et al., 2010). A causal role of parietal cortex for an inhibition of goal-directed actions has been recently shown through electrical stimulation (for discussion see Lindner, 2018). In natural situations, however, spatial goals and objects/regions that we need to avoid are often present simultaneously (like the panhandle next to another hotplate). We here seek for direct evidence that movement trajectories in such situations reflect the output of a spatial integration of action plans and action inhibition.

Agency Attribution - Mechanisms and Disorders

A key constituent of the "Self" is "agency". Agency refers to our ability to identify whether or not our movements and their sensory consequences are caused by ourselves. Deficits of this ability do, accordingly, dissolve the border between self and non-self, as is for instance the case in certain Schizophrenia patients. A healthy subject can attribute agency to self-produced sensory information on the basis of her own motor commands: these commands allow to predict and, thus, to identify the sensory consequences of her actions. We have shown that deficits of this predictive mechanism (also termed forward model, efference copy, or corollary discharge) explain disorders of the Self in Schizophrenia (Lindner et al., 2005; Synofzik et al., 2010). We have further shown that sensory predictions are recalibrated by sensory feedback on a short timescale (Synofzik et al., 2006; Wilke et al., 2013). Moreover, this plasticity is mediated by the cerebellum (Lindner et al., 2006; Synofzik et al., 2008; Roth et al., 2013) and, likely, is not only optimizing perceived agency but also motor control. Using 2D virtual reality reach setups (figure; also see Methods) we currently detail the mechanisms of agency attribution, their neural underpinnings, and their disturbance in various neuropsychiatric disease.

Ongoing Research on Agency and its Disorders

  • Disturbance of the Sense of Agency in Obsessive-Compulsive Disorder and its Modulation by Social Context. Manuel Roth. In collaboration with Andreas J. Fallgatter, Andreas Wittorf and Aiste Jusyte, University Department of Psychiatry and Psychotherapy, Tübingen, Germany. [manuscript available]

  • Impaired perception of temporal contiguity between action and effect is associated with disorders of agency in Schizophrenia. Manuel Roth. In collaboration with Dr. Marc Buehner, School of Psychology, Cardiff University, UK, Dr. Hong Yu Wong, Centre for Integrative Neuroscience, Tübingen, Germany, and Prof. Dr. Dirk Wildgruber, University Department of Psychiatry and Psychotherapy, Tübingen, Germany. [abstract] [manuscript available]

  • The negative self - biased agency attribution in major depressive disorder. Felicia Membarth. In collaboration with Prof. Dr. Christian Plewnia, University Department of Psychiatry and Psychotherapy, Tübingen, Germany.

  • Principle mechanisms of agency attribution and their alteration in stroke patients. Julius Böhme & Karla Lauer. In collaboration with Prof. Dr. Dr. Hans-Otto Karnath, Dr. Marc Himmelbach & Dr. Matthis Synofzik, Hertie-Institute, Tübingen, Germany. Coworkers: Manuel Roth, [abstract]

  • The detached self: Comparing depersonalization / derealization-like experiences arising in meditation vs. other contexts. Erola Pons.

  • Metacognition in Agency - Implications for Neuropsychiatric Diseases? Eva Vennemann.

  • Self-Action Perception of Movement Amplitude vs. Movement Direction and its Improvment through Vibrotactile Feedback. Lena Stöckl.

  • How perceived agency and personality influence sensorimotor learning. Matthias Felk.

  • Do deficits in agency attribution in Pakinson's disease reflect an attenuation of "intentional saliency"? In collaboration with PD Dr. Matthis Synofzik, Hertie-Institute, Tübingen, Germany, and PD Dr. Tobias Wächter, Neurologie, Reha-Zentrum Bad Gögging, Germany. [manuscript available]

Working Memory and Cognitive Aging

By recruiting “mirror” regions in the contralateral cerebral hemisphere of prefrontal cortex elderly subjects are able to master challenging cognitive tasks despite cognitive decline. Using highly demanding working memory tasks during fMRI we have shown that such bilateral prefrontal activation is not age-specific but reflects a general coping strategy that is independent of age, task content and brain region (Höller-Wallscheid et al. 2017). We currently investigate whether such cross-hemispheric recruitment is present also beyond frontal cortex and in tasks other than working memory. In addition we try to use the so-called “bilateral field advantage effect” as a means to externally trigger bilateral representation and to improve working memory performance despite cognitive decline.

Building on preliminary evidence (Pilacinski et al., 2020) we currently try to challenge classic conceptions of working memory: We investigate whether the way sensory information is maintained in working memory critically depends on its future use.

Ongoing Research on Working Memory and Cognitive Aging

  • Improving Working Memory. Inspired by the work of Melanie Höller-Wallscheid, Teresa Kohler & Nina Röhm currently investigate by means of psychophysics and fMRI whether and how a “bilateral field advantage effect” could improve working memory performance and bilaterality. Our goal is to devise a simple behavioral strategy to support working memory in people with MCI and early dementia.

  • Decoding Working Memory. Kreshnik Bickaj. Extending the work of Pilacinski et al., 2022, we try to find evidence for verbal/spatial visual information being maintained differently in the brain, namely as dependent on whether subjects will later use the respective material for a verbal vs. a spatial finger movement response. With this we’d like to demonstrate that working memory representations consider differences in the future use of the same memory material.

Influence of Static Magnetic Field inside MRI-scanners on Spatial Attention and Behavior

The static magnetic field inside MRI-scanners induces a tonic magnetic-vestibular stimulation (MVS). MVS not only leads to a strong and persistent vestibulo-ocular reflex, which chiefly surfaces in the horizontal domain. Together with Prof. Dr. Dr. Hans-Otto Karnath and Dr. Daniel Wiesen we recently demonstrated that MVS also introduces a horizontal bias in goal directed spatial attention and behavior (Lindner et al., 2021). Extending this collaborative research with the Karnath-lab, we currently probe whether MVS could be used to ameliorate spatial neglect after stroke.

Ongoing Research on Magnetic-Vestibular Stimulation inside MRI

  • Reducing spatial neglect after stroke through MVS inside a 3T MRI scanner. Prof. Dr. Dr. Hans-Otto Karnath, Hannah Rosenzopf, Stefan Smaczny, Axel Lindner. [preprint]

Economic Decision Making and Choice Overload

In consumer decision making there is a point at which the benefits of ever increasing choice options are outweighed by the costs of choosing from multiple alternatives, ultimately leading to choice overload. We recently demonstrated that brain activity in dorsal striatum and the anterior cingulate cortex reflect the net-benefit of increasing choice sets and speculated that this representation of choice set value motivates (or demotivates) processes of decision making (Reutskaja et al., 2018). We currently investigate whether our results generalize to other decision scenarios that may entail other types of cognitive costs and benefits.

Ongoing Research on Economic Decision Making and Cognitive Overload

  • Cognitive overload in accounting decisions. In collaboration with Prof. Dr. Burkhard Pedell, Dr. Ann Tank & Yannick Sam Schüßler, Chair of Management Accounting and Control, University of Stuttgart, Germany. [Publication of PhD Thesis] [manuscript in preparation]

The Neural Basis of Perceptual Decisions and Perceptual Grouping

Our holistic perception of the environment is a result of processes, which group the fragments of information arriving at the retina in order to form entities or objects. Studies on simultanagnosia patients, who lost the ability to perceive a visual scene holistically, emphasize the importance of parieto-occipital cortex as substrate for perceptual grouping. To study perceptual (spatial) grouping we utilize a bistable Ternus-Display that does - depending on how sensory information is grouped - lead to the perception of either element motion or group motion: Element motion (a single dot is "jumping" left and right) is commonly perceived in the upper animation of the Ternus diplay on the right while group motion (a group of three dots is "jumping" left and right) is typically perceived in the lower animation. Using this bistable stimulus in combination with fMRI, we provided preliminary evidence that parieto-occipital cortex does indeed serve as a substrate for spatial grouping (Kutscheid et al., 2014).

In a distinct line of collaborative research on perceptual decision making, we applied delayed response tasks to separate perceptual vs. motor decisions. Furthermore, our approach enabled us to trace a fine-grained functional somatosensory-to-motor cascade of cortical areas engaged in the perceptual decision making process during tactile pattern discrimination (Li Hegner et al., 2015 & 2017).

Ongoing Research on Perceptual Decisions and Grouping

  • The Role of Parietal Cortex in Mediating Perceptual Grouping: Katrin Kutscheidt, Katrina R. Quinn & Sarah Trillsam. fMRI and MEG studies using a bistable Ternus display. In collaboration with Dr. Elisabeth Hein, Evolutionary Cognition Lab, Department of Psychology, Tübingen, Germany, and Prof. Dr. Cristoph Braun, MEG-Centre, Tübingen, Germany. [abstract] [manuscript in preparation]