Johannes Algermissen
@johalgermissen.bsky.social
Postdoc UniOxford with MKFlugge, past PhD
DondersInst, into decision-making, learning, ultrasound stimulation, improving psychology & neuroscience. he/him
DondersInst, into decision-making, learning, ultrasound stimulation, improving psychology & neuroscience. he/him
Congrats newly minted Dr. @ben-kop.bsky.social
on an awesome PhD defense! 🤝🙇
on an awesome PhD defense! 🤝🙇
November 5, 2025 at 5:13 PM
Congrats newly minted Dr. @ben-kop.bsky.social
on an awesome PhD defense! 🤝🙇
on an awesome PhD defense! 🤝🙇
... in behaviour, mIns-TUS did not affect the emotional action biases. However, it did increase participants' propensity to repeat responses, reflected in a higher positive learning rate ... (11/15)
August 20, 2025 at 6:07 AM
... in behaviour, mIns-TUS did not affect the emotional action biases. However, it did increase participants' propensity to repeat responses, reflected in a higher positive learning rate ... (11/15)
... finally, we turned to our active control region, the mIns. TUS to mIns did not change RS-connectivity. However, it increased GABA measured with MRS, suggesting the same ultrasound protocol might be inhibitory in the BLA, but excitatory in the mIns... (10/15)
August 20, 2025 at 6:07 AM
... finally, we turned to our active control region, the mIns. TUS to mIns did not change RS-connectivity. However, it increased GABA measured with MRS, suggesting the same ultrasound protocol might be inhibitory in the BLA, but excitatory in the mIns... (10/15)
… under TUS to the BLA, however, participants showed a stronger tendency to approach neutral faces, an effect that scaled with the volume of bilaterally stimulated tissue. Similar, RTs for happy and neutral faces slowed down. There was however no change in learning from feedback ... (9/15)
August 20, 2025 at 6:06 AM
… under TUS to the BLA, however, participants showed a stronger tendency to approach neutral faces, an effect that scaled with the volume of bilaterally stimulated tissue. Similar, RTs for happy and neutral faces slowed down. There was however no change in learning from feedback ... (9/15)
... overall, participants showed an emotional bias, approach happy more than neutral and angry faces (with the same bias in RTs). This was also captured by a reinforcement learning model with separate action biases for the different emotions .... (8/15)
August 20, 2025 at 6:06 AM
... overall, participants showed an emotional bias, approach happy more than neutral and angry faces (with the same bias in RTs). This was also captured by a reinforcement learning model with separate action biases for the different emotions .... (8/15)
… third, we had participants play in novel task in which saw mini-blocks of happy/neutral/angry faces and had to learn from trial-and-error whether to approach or avoid those face (button press + faces grows/shrinks). After 4-7 trials, a new mini-block with a different emotion started... (7/15)
August 20, 2025 at 6:05 AM
… third, we had participants play in novel task in which saw mini-blocks of happy/neutral/angry faces and had to learn from trial-and-error whether to approach or avoid those face (button press + faces grows/shrinks). After 4-7 trials, a new mini-block with a different emotion started... (7/15)
... second, we found TUS to the BLA change metabolite concentration in the BLA, specifically increasing GABA, suggesting a net inhibition (decreased E/I balance) after TUS ... (6/15)
August 20, 2025 at 6:03 AM
... second, we found TUS to the BLA change metabolite concentration in the BLA, specifically increasing GABA, suggesting a net inhibition (decreased E/I balance) after TUS ... (6/15)
... first, we found that TUS to the BLA reduces it resting-state connectivity to several mono-/di-synaptically connected regions. Effects occurred immediately after stimulation as well as 90 minutes later, corroborating findings that TUS can change neural activity for > 1 hour ... (5/15)
August 20, 2025 at 6:03 AM
... first, we found that TUS to the BLA reduces it resting-state connectivity to several mono-/di-synaptically connected regions. Effects occurred immediately after stimulation as well as 90 minutes later, corroborating findings that TUS can change neural activity for > 1 hour ... (5/15)
... so we invited 33 healthy participants to 3 sessions (basolateral amygdala (BLA) stimulation, mid-insula (mIns) stimulation, or sham) in which they received 80 seconds of offline TUS and then went to the MRI scanner for 1.5h to collect fMRI, MRS, and behavioural data ... (4/15)
August 20, 2025 at 6:02 AM
... so we invited 33 healthy participants to 3 sessions (basolateral amygdala (BLA) stimulation, mid-insula (mIns) stimulation, or sham) in which they received 80 seconds of offline TUS and then went to the MRI scanner for 1.5h to collect fMRI, MRS, and behavioural data ... (4/15)
Very happy to share my first preprint from @oxexppsy.bsky.social @oxneuro.bsky.social ! We (me + co-first authors @lilweb.bsky.social @mirunarascu.bsky.social + PI @mkflugge.bsky.social + many others) used transcranial focused ultrasound stimulation (TUS/tFUS/LIFU) of the human amygdala ... (1/15)
August 20, 2025 at 5:58 AM
Very happy to share my first preprint from @oxexppsy.bsky.social @oxneuro.bsky.social ! We (me + co-first authors @lilweb.bsky.social @mirunarascu.bsky.social + PI @mkflugge.bsky.social + many others) used transcranial focused ultrasound stimulation (TUS/tFUS/LIFU) of the human amygdala ... (1/15)
These effects were best captured by a new computational learning model in which participants learn to flexibly recruit cognitive control to suppress their Pavlovian biases in situations in which this is not helpful. Such a model had particular good fit in individuals scoring high on AD!
February 12, 2025 at 2:54 PM
These effects were best captured by a new computational learning model in which participants learn to flexibly recruit cognitive control to suppress their Pavlovian biases in situations in which this is not helpful. Such a model had particular good fit in individuals scoring high on AD!
Intriguingly, AD and CIT loaded differently on behaviour: While CIT was associated with worse performance, AD was correlated with better performance, particularly so on the (difficult) incongruent trials! Also, people scoring high on AD showed slower RTs, looking like increased cognitive control...
February 12, 2025 at 2:53 PM
Intriguingly, AD and CIT loaded differently on behaviour: While CIT was associated with worse performance, AD was correlated with better performance, particularly so on the (difficult) incongruent trials! Also, people scoring high on AD showed slower RTs, looking like increased cognitive control...
First of all, we replicated a (by now well-established) 3-factor solution first described by @clairegillan.bsky.social with separate factors for anxiety-depression (AD), compulsion and intrusive thoughts (CIT), and social withdrawal (SW) ...
February 12, 2025 at 2:52 PM
First of all, we replicated a (by now well-established) 3-factor solution first described by @clairegillan.bsky.social with separate factors for anxiety-depression (AD), compulsion and intrusive thoughts (CIT), and social withdrawal (SW) ...
But so far, this hasn't been studied in a large, well-powered sample, and it's not clear whether biases map onto a single uniform symptom dimension or not. We collected data from N = 500 people playing the Motivational Go/NoGo Task online and filling out psychiatric questionnaires...
February 12, 2025 at 2:51 PM
But so far, this hasn't been studied in a large, well-powered sample, and it's not clear whether biases map onto a single uniform symptom dimension or not. We collected data from N = 500 people playing the Motivational Go/NoGo Task online and filling out psychiatric questionnaires...
Importantly, EEG correlates of biased prediction errors in cortical regions (dACC, PCC) precede those of subcortical regions (striatum).
January 5, 2024 at 12:08 PM
Importantly, EEG correlates of biased prediction errors in cortical regions (dACC, PCC) precede those of subcortical regions (striatum).
Happy the 2nd empirical chapter has (finally!) been published in Nature Communications: nature.com/articles/s41...
In this work, we used simultaneous EEG-fMRI recordings to investigate the temporal cascade of biased learning from rewards and punishments across cortex and subcortex.
In this work, we used simultaneous EEG-fMRI recordings to investigate the temporal cascade of biased learning from rewards and punishments across cortex and subcortex.
January 5, 2024 at 12:07 PM
Happy the 2nd empirical chapter has (finally!) been published in Nature Communications: nature.com/articles/s41...
In this work, we used simultaneous EEG-fMRI recordings to investigate the temporal cascade of biased learning from rewards and punishments across cortex and subcortex.
In this work, we used simultaneous EEG-fMRI recordings to investigate the temporal cascade of biased learning from rewards and punishments across cortex and subcortex.
5/8 Second finding: Pupil dilation dilates more for Go than NoGo responses (old hat), but particularly so for Go responses to Avoid cues! This might reflect an underexplored facet of cognitive control—mobilizing effort to invigorate actions against forces holding us back.
December 28, 2023 at 6:56 PM
5/8 Second finding: Pupil dilation dilates more for Go than NoGo responses (old hat), but particularly so for Go responses to Avoid cues! This might reflect an underexplored facet of cognitive control—mobilizing effort to invigorate actions against forces holding us back.
4/8 Still, gaze and pupil data shed new light on Pavlovian biases and how they can be overcome. First finding:
Avoid cues (threat of punishment) induce a “freezing of gaze” relative to Win cues (reward prospect), in line with recent findings, but even in such a simple task!
Avoid cues (threat of punishment) induce a “freezing of gaze” relative to Win cues (reward prospect), in line with recent findings, but even in such a simple task!
December 28, 2023 at 6:55 PM
4/8 Still, gaze and pupil data shed new light on Pavlovian biases and how they can be overcome. First finding:
Avoid cues (threat of punishment) induce a “freezing of gaze” relative to Win cues (reward prospect), in line with recent findings, but even in such a simple task!
Avoid cues (threat of punishment) induce a “freezing of gaze” relative to Win cues (reward prospect), in line with recent findings, but even in such a simple task!
3/8 However, the subliminal priming manipulation had no measurable effect—not on responses, nor RTs, nor pupil dilation. Which shows that manipulations can fail—even when used by previously published studies and appearing successful in four pilot participants…
December 28, 2023 at 6:55 PM
3/8 However, the subliminal priming manipulation had no measurable effect—not on responses, nor RTs, nor pupil dilation. Which shows that manipulations can fail—even when used by previously published studies and appearing successful in four pilot participants…
2/8 … which we tested by both measuring and manipulating trial-by-trial arousal using pupillometry and a subliminal priming manipulation (angry vs. neutral faces). We expected stronger biases under high vs. low arousal (both induced and measured).
December 28, 2023 at 6:55 PM
2/8 … which we tested by both measuring and manipulating trial-by-trial arousal using pupillometry and a subliminal priming manipulation (angry vs. neutral faces). We expected stronger biases under high vs. low arousal (both induced and measured).
4/9 We tested both hypotheses in behavioral data from N = 54 participants. Main results:
1. Robust Pavlovian biases in responses and RTs.
2. No effect of high vs. low stakes on responses.
3. Globally slower RTs under high stakes--especially for motivational incongruent cues…
1. Robust Pavlovian biases in responses and RTs.
2. No effect of high vs. low stakes on responses.
3. Globally slower RTs under high stakes--especially for motivational incongruent cues…
December 28, 2023 at 6:10 PM
4/9 We tested both hypotheses in behavioral data from N = 54 participants. Main results:
1. Robust Pavlovian biases in responses and RTs.
2. No effect of high vs. low stakes on responses.
3. Globally slower RTs under high stakes--especially for motivational incongruent cues…
1. Robust Pavlovian biases in responses and RTs.
2. No effect of high vs. low stakes on responses.
3. Globally slower RTs under high stakes--especially for motivational incongruent cues…
3/9 Hypothesis H2: higher stakes = higher motivation for accurate performance. When Pavlovian biases are incongruent with required responses, people might be more motivated to recruit cognitive control and inhibit the biases when they are maladaptive (see EVC theory)…
December 28, 2023 at 6:10 PM
3/9 Hypothesis H2: higher stakes = higher motivation for accurate performance. When Pavlovian biases are incongruent with required responses, people might be more motivated to recruit cognitive control and inhibit the biases when they are maladaptive (see EVC theory)…
Having defended my PhD earlier this year, still before the end of 2023, I’m happy to preprint two small projects I did which did not make it into my thesis. Both pre-registered, but we did not find support for our initial hypotheses. Still worth sharing! Two threads…
December 28, 2023 at 6:09 PM
Having defended my PhD earlier this year, still before the end of 2023, I’m happy to preprint two small projects I did which did not make it into my thesis. Both pre-registered, but we did not find support for our initial hypotheses. Still worth sharing! Two threads…