Electrophysiology

Neural oscillations are often proposed to support brain computation by routing information, organizing cell assemblies, or shaping coding dynamics. Yet these ideas usually assume rhythms that are strong, sustained, and regular, whereas in vivo oscillations are often weak, transient, noisy, and variable in frequency and phase. In this talk, I will argue that such “no-metronome” oscillations are not just noisy fluctuations, but coordinated complex dynamics with functional consequences. Combining analyses of neural activity recordings during actual behavior (mice and non-human-primate LFPs and human EEG) with computational modelling, I will discuss evidence that transient oscillatory events can carry task-relevant information and support flexible communication through spatiotemporally structured relationships across populations, timescales, and frequencies. Together, these results suggest that oscillatory weakness and weirdness are not just imperfections, noise to average-out, but part of the functional repertoire of neural computation Presented in the van Vreeswijk Theoretical Neuroscience Seminar series (formerly WWTNS) on 2026-05-06. Recording duration: 00:40:47.

Reward expectations – one’s prediction about the likelihood of future outcomes - play a central role in shaping the satisfaction derived from those outcomes. Most existing research treats expectations as static, assuming they remain fixed in time. However, real-life expectations are often dynamic, fluctuating as new information becomes available. For example, during a soccer game, your expectations of seeing your team winning will likely rise and fall as the game unfolds. In the main part of this talk, I will present a series of studies demonstrating that human expectations can be tracked at sub-second timescales. Using slot machines as a case study, we leverage the continuous deceleration of the reels to elicit moment-by-moment fluctuations in rewardexpectations. To capture these dynamics, we take complementary approaches: we use the high temporal resolution of electroencephalography (EEG) to track neural signatures of evolving expectations, and we develop a novel behavioral paradigm (“Slot or Not”) designed to measure changes in expectations via betting behavior. Across four studies, we show that expectations fluctuate continuously and can be tracked both behaviorally and neurally. Extending these findings, a subsequent intracranial study shows that the human orbitofrontal cortex (OFC) encodes the moment-by-moment changes of reward expectations. In the second part of this talk, I will return to the relationship between expectations andsatisfaction. If expectations shape satisfaction, and if they are best conceptualized as dynamic trajectories rather than static quantities, a key question arises: does the trajectory leading up to an outcome influence how that outcome is evaluated? I will outline a new research direction aimed at formalizing this relationship using computational modeling. This is ongoing work, and I welcome feedback on how best to formalize these ideas. Finally, I will discuss potential extensions of this framework to psychopathology, asking whether alterations in dynamic expectations may characterize conditions such as Major Depressive Disorder and Gambling disorder. Together, this work introduces a new framework for studying expectations as dynamic processes, offering a richer understanding Presented in the van Vreeswijk Theoretical Neuroscience Seminar series (formerly WWTNS) on 2026-04-29. Recording duration: 00:42:25.

Neural activity is often analyzed with respect to external referents, such as the onset of a sensory stimulus or an overt motor action. Simultaneous recordings allow referencing neurons’ activity to each other and thus detecting signals that are internal to the organism. Further, multi-region simultaneous recordings allow observing how these internal signals are coordinated across the brain. Following this logic in rats performing a perceptual decision-making task, we recorded simultaneously from thousands of neurons across up to 20 brain regions at once. Here we report two internal signals which we found to profoundly shape decision-related neural dynamics and brain states. First, we decoded the continuously evolving decision state separately from each region, and found surprisingly large magnitude co-fluctuations in these measures. Dimensionality analysis showed these to be dominated by a single state variable, suggesting that only a single decision-making computation, not multiple parallel computations, are being carried out during the analyzed period. Second, we found that the precise time the subject commits to a decision – a covert event that we decoded from large-scale neural activity in primary motor cortex – was accompanied by a coordinated change, across the brain, from a decision formation to a post-commitment state. The two states differ substantially in their choice-predictive neural dynamics and in their inter-region correlations. Therefore, knowing the time of this state change on single trials is needed to correctly parse fundamentally different phases of decision-making. Overall, our data suggest that internally-referenced signals and state changes, not timelocked to external events but detectable through simultaneous recordings, are major features of neural activity during cognition. VVTNS 2026 Opening Lecture. Presented in the van Vreeswijk Theoretical Neuroscience Seminar series (formerly WWTNS) on 2026-01-07. Recording duration: 00:42:45.

Kenneth Harris discusses what simultaneous recordings from many cells reveal about visual information encoded by neuronal populations.

NIMH supports exploratory research using opportunities for invasive recording and stimulation in humans to understand neural circuits relevant to mental health disorders. Projects should connect measurements or causal interventions with mechanistic questions about brain function. This R21 mechanism provides up to USD 275,000 in direct costs over two years, with no more than USD 200,000 in either year. The next deadline for new applications is 16 October 2026, at 5 p.m. in the applicant organisation’s local time. Therapeutic device intervention trials are outside this call’s intended scope.

Investigate human brain circuits underlying emotion and cognition, with the goal of improving precision neuromodulation. Research combines intracranial recordings, stimulation, single-neuron measurements, functional imaging and computational network models in a clinical neuroscience environment. The position is full-time and includes opportunities to connect causal circuit measurements with psychiatric questions. Applications close on 17 October 2026.

Postdoctoral scholarship in the Stagkourakis Lab studying neural control of survival behaviors using in vivo large-scale electrophysiology, advanced imaging, and causal perturbations in freely moving mice at Biomedicum and SciLifeLab.

A four-year FPI-funded experimental PhD position is available in Jake Watson's new Human Circuits Barcelona research team at Hospital del Mar Research Institute, Barcelona, Spain. The project investigates how human cells and synapses generate neural computations and how these processes change in epilepsy. Working closely with the Hospital del Mar Epilepsy Unit and Neurosurgery team, researchers apply advanced imaging and patch-clamp electrophysiology to rodent and neurosurgical human brain samples. The group combines electrophysiology with super-resolution imaging to study the organization and function of cells, synapses, and neural circuits. It is based at the Barcelona Biomedical Research Park (PRBB), Carrer del Doctor Aiguader 88, Barcelona. Jake Watson is a Ramón y Cajal Fellow; his previous research includes doctoral work at the MRC Laboratory of Molecular Biology in Cambridge and postdoctoral work at IST Austria. How to apply: Email a CV including one or two referees and a short expression of interest to jwatson@researchmar.net. Applications are reviewed continuously until 1 November 2026 . Funding and duration: Four years of FPI funding. Salary and start date are not specified in the lab's announcement. Research team and open position: humancircuits.net/people . Download the position flyer .

Investigate human brain circuits underlying emotion and cognition, with the goal of improving precision neuromodulation. Research combines intracranial recordings, stimulation, single-neuron measurements, functional imaging and computational network models in a clinical neuroscience environment. The position is full-time and includes opportunities to connect causal circuit measurements with psychiatric questions. Applications close on 17 October 2026.

NIMH supports exploratory research using opportunities for invasive recording and stimulation in humans to understand neural circuits relevant to mental health disorders. Projects should connect measurements or causal interventions with mechanistic questions about brain function. This R21 mechanism provides up to USD 275,000 in direct costs over two years, with no more than USD 200,000 in either year. The next deadline for new applications is 16 October 2026, at 5 p.m. in the applicant organisation’s local time. Therapeutic device intervention trials are outside this call’s intended scope.

Margaret Livingstone of Harvard Medical School presents in Princeton Neuroscience Institute's public seminar series. Livingstone's laboratory studies how visual recognition occurs in the primate brain using behavior, brain imaging, and electrophysiology.