The natural course of idiopathic cervical dystonia.

Idiopathic cervical dystonia (ICD) is by far the largest subgroup of dystonia. Still, its natural course is largely unknown. We studied the natural course of 100 ICD patients from our botulinum toxin clinics (age at ICD onset 45.8 ± 13.5 years, female/male ratio 2.0) over a period of 17.5 ± 11.5 years with follow-ups during botulinum toxin therapy and with semi-structured interviews. Two courses of ICD could be distinguished by symptom development of more or less than 6 months. ICD-type 2 was less frequent (19% vs 81%, p < 0.001), had a more rapid onset (8.7 ± 8.0 weeks vs 3.8 ± 3.5 years), a higher remission rate (92% vs 5%, p < 0.001) and a higher prevalence of excessive psychological stress preceding ICD (63% vs 1%, p < 0.001). In both ICD-types, the plateau phase was non-progressive. Significant differences in patient age at ICD onset, latency and extent of remission, female/male ratio and prevalence of family history of dystonia could not be detected. ICD is a non-progressive disorder. ICD-type 1 represents the standard course. ICD-type 2 features rapid onset, preceding excessive psychological stress and a high remission rate. These findings will improve prognosis, treatment strategies and understanding of underlying disease mechanisms. They contradict the widespread fear of patients of a constant and continued decline of their condition. Excessive psychological stress may be an epigenetic factor triggering the manifestation of genetically predetermined dystonia.

Excessive psychological stress preceding the onset of idiopathic cervical dystonia.

Idiopathic cervical dystonia (ICD) is the largest subgroup of dystonia. Psychological stress as a triggering factor has long been discussed, but detailed descriptions are lacking. We report on a group of 13 patients with ICD and preceding excessive psychological stress (age at ICD onset 39.0 ± 13.9 years, 7 females, 6 males). The observation period was 7.8 ± 5.0 years. Excessive psychological stress included partner conflicts (divorce and separation, domestic violence), special familial burdens, legal disputes and migration. It started 8.3 ± 3.9 months before ICD onset. In 85% of our patients (typical cases), ICD developed within 5.8 ± 4.4 weeks, then lasted 18.5 ± 8.3 months, before it started to remit 2.7 ± 0.8 years after its onset to 54.5 ± 35.3% of its maximal severity. Idiopathic dystonia is thought to be based upon a genetic predisposition triggered by epigenetic factors. Our study suggests that excessive psychological stress could be one of them. Pathophysiologic elements are only vaguely identified, but could include the endoplasmic reticulum stress response, cerebellar 5HT-2A receptors and the metabolism of heat shock proteins. Whilst the clinical presentation of ICD preceded by excessive psychological stress is typical, its course is atypical with rapid onset and fast and substantial remission.

The relation between implicit statistical learning and proactivity as revealed by EEG.

Environmental events often occur on a probabilistic basis but can sometimes be predicted based on specific cues and thus approached proactively. Incidental statistical learning enables the acquisition of knowledge about probabilistic cue-target contingencies. However, the neural mechanisms of statistical learning about contingencies (SLC), the required conditions for successful learning, and the role of implicit processes in the resultant proactive behavior are still debated. We examined changes in behavior and cortical activity during an SLC task in which subjects responded to visual targets. Unbeknown to them, there were three types of target cues associated with high-, low-, and zero target probabilities. About half of the subjects spontaneously gained explicit knowledge about the contingencies (contingency-aware group), and only they showed evidence of proactivity: shortened response times to predictable targets and enhanced event-related brain responses (cue-evoked P300 and contingent negative variation, CNV) to high probability cues. The behavioral and brain responses were strictly associated on a single-trial basis. Source reconstruction of the brain responses revealed activation of fronto-parietal brain regions associated with cognitive control, particularly the anterior cingulate cortex and precuneus. We also found neural correlates of SLC in the contingency-unaware group, but these were restricted to post-target latencies and visual association areas. Our results document a qualitative difference between explicit and implicit learning processes and suggest that in certain conditions, proactivity may require explicit knowledge about contingencies.

Musical Expertise and Executive Functions in Experienced Musicians.

Extensive music practice has been suggested to enhance the development of cognitive abilities over and above musical expertise. Executive functions (EFs) have been particularly investigated, given their generalizability across different domains and their crucial role in almost all aspects of cognition. However, the relationship between musical expertise and EFs is still not completely understood, as several studies have reported conflicting results. The present study aims to investigate the relationship between musical expertise and EFs, determining which facets-if any-of EFs might be particularly relevant to extensive music practice. Thirty-five student pianists completed a set of neuropsychological tasks which assessed EFs (the Trail Making Task, Design Fluency, Numerical Stroop, and the Tower of London). They also performed a short musical excerpt inspired by the piano literature. Musical expertise was assessed by considering three parameters, namely the highest academic degree in music, the lifetime amount of music practice, and the quality of the sample-based musical performance. The results indicate that postgraduate piano students did not show advantages in EFs compared to undergraduate piano students. More extensive lifetime practice in music was solely associated with faster visual reaction times on the Numerical Stroop task. The Trail Making and Design Fluency scores were significant predictors of the quality of the sample-based musical performance. In conclusion, the present data suggests that EFs and the amount of music practice do not seem to be correlated in student pianists. Nevertheless, some facets of EFs and the quality of musical performance may share substantial amounts of variance.

Habits, Goals, and Behavioral Signs of Cognitive Perseveration on Wisconsin Card-Sorting Tasks.

Wisconsin card-sorting tasks provide unique opportunities to study cognitive flexibility and its limitations, which express themselves behaviorally as perseverative errors (PE). PE refer to those behavioral errors on Wisconsin card-sorting tasks that are committed when cognitive rules are maintained even though recently received outcomes demand to switch to other rules (i.e., cognitive perseveration). We explored error-suppression effects (ESE) across three Wisconsin card-sorting studies. ESE refer to the phenomenon that PE are reduced on repetitive trials compared to non-repetitive trials. We replicated ESE in all three Wisconsin card-sorting studies. Study 1 revealed that non-associative accounts of ESE, in particular the idea that cognitive inhibition may account for them, are not tenable. Study 2 suggested that models of instrumental learning are among the most promising associative accounts of ESE. Instrumental learning comprises goal-directed control and the formation of corresponding associative memories over and above the formation of habitual memories according to dual-process models of instrumental learning. Study 3 showed that cognitive, rather than motor, representations of responses should be conceptualized as elements entering goal-directed instrumental memories. Collectively, the results imply that ESE on Wisconsin card-sorting tasks are not only a highly replicable phenomenon, but they also indicate that ESE provide an opportunity to study cognitive mechanisms of goal-directed instrumental control. Based on the reported data, we present a novel theory of cognitive perseveration (i.e., the 'goal-directed instrumental control' GIC model), which is outlined in the Concluding Discussion.

Dopaminergic and norepinephrinergic modulation of endogenous event-related potentials: A systematic review and meta-analysis.

Event-related potentials (ERPs) represent the cortical processing of sensory, motor or cognitive functions invoked by particular events or stimuli. A current theory posits that the catecholaminergic neurotransmitters dopamine (DA) and norepinephrine (NE) modulate a number of endogenous ERPs during various cognitive processes. This manuscript aims to evaluate a leading neurotransmitter hypothesis with a systematic overview and meta-analysis of pharmacologic DA and NE manipulation of specific ERPs in healthy subjects during executive function. Specifically, the frontally-distributed P3a, N2, and Ne/ERN (or error-related negativity) are supposedly modulated primarily by DA, whereas the parietally-distributed P3b is thought to be modulated by NE. Based on preceding research, we refer to this distinction between frontally-distributed DA-sensitive and parietally-distributed NE-sensitive ERP components as the Extended Neurobiological Polich (ENP) hypothesis. Our systematic review and meta-analysis indicate that this distinction is too simplistic and many factors interact with DA and NE to influence these specific ERPs. These may include genetic factors, the specific cognitive processes engaged, or elements of study design, i.e. session or sequence effects or data-analysis strategies.

Cognition in patients with neuromyelitis optica spectrum disorders: A prospective multicentre study of 217 patients (CogniNMO-Study).

BACKGROUND: There is limited and inconsistent information on the prevalence of cognitive impairment in neuromyelitis optica spectrum disorders (NMOSD). OBJECTIVE: To assess cognitive performance and changes over time in NMOSD. METHODS: This study included data from 217 aquaporin-4-IgG-seropositive (80%) and double-seronegative NMOSD patients. Cognitive functions measured by Symbol Digit Modalities Test (SDMT), Paced Auditory Serial-Addition Task (PASAT), and/or Multiple Sclerosis Inventory Cognition (MuSIC) were standardized against normative data (N = 157). Intraindividual cognitive performance at 1- and 2-year follow-up was analyzed. Cognitive test scores were correlated with demographic and clinical variables and assessed with a multiple linear regression model. RESULTS: NMOSD patients were impaired in SDMT (p = 0.007), MuSIC semantic fluency (p < 0.001), and MuSIC congruent speed (p < 0.001). No significant cognitive deterioration was found at follow-up. SDMT scores were related to motor and visual disability (pBon < 0.05). No differences were found between aquaporin-4-IgG-seropositive and double-seronegative NMOSD. CONCLUSIONS: A subset of NMOSD patients shows impairment in visual processing speed and in semantic fluency regardless of serostatus, without noticeable changes during a 2-year observation period. Neuropsychological measurements should be adapted to physical and visual disabilities.

Botulinum toxin antibody titres: measurement, interpretation, and practical recommendations.

Botulinum toxin (BT) therapy may be blocked by antibodies (BT-AB) resulting in BT-AB induced therapy failure (ABF). BT-AB may be detected by the mouse lethality assay (MLA), the mouse diaphragm assay (MDA) and the sternocleidomastoid test (SCMT). For the first time, we wanted to compare all three BT-AB tests and correlate them to subjective complaint of complete or partial secondary therapy failure in 37 patients with cervical dystonia (25 females, 12 males, age 51.2 ± 11.4 years, disease duration 12.4 ± 6.3 years). Complaint of therapy failure was not correlated with any of the BT-AB tests. MDA and MLA are closely correlated, indicating that the MDA might replace the MLA as the current gold standard for BT-AB measurement. The SCMT is closely correlated with MDA and MLA confirming that BT-AB titres and BT's paretic effect are in a functional balance: low BT-AB titres are reducing BT's paretic effect only marginally, whereas high BT-AB titres may completely block it. When therapy failure is classified as secondary and permanent, BT-AB evaluation is recommended and any BT-AB test may be applied. For MDA > 10 mU/ml, MLA > 3 and SCMT < 25%, ABF is highly likely. MDA < 0.6 mU/ml are therapeutically irrelevant. They are neither correlated with pathologic MLA nor with pathologic SCMT. They should not be the basis for treatment decisions, such as switching dystonia therapy to deep brain stimulation. All other results are intermediate results. Their interactions with therapy efficacy is unpredictable. In these cases, BT-AB tests should be repeated or one or two additional test methods should be applied.

Towards the Validation of Executive Functioning Assessments: A Clinical Study.

Neuropsychological assessment needs a more profound grounding in psychometric theory. Specifically, psychometrically reliable and valid tools are required, both in patient care and in scientific research. The present study examined convergent and discriminant validity of some of the most popular indicators of executive functioning (EF). A sample of 96 neurological inpatients (aged 18-68 years) completed a battery of standardized cognitive tests (Raven's matrices, vocabulary test, Wisconsin Card Sorting Test, verbal fluency test, figural fluency test). Convergent validity of indicators of intelligence (Raven's matrices, vocabulary test) and of indicators of EF (Wisconsin Card Sorting Test, verbal fluency test, figural fluency) were calculated. Discriminant validity of indicators of EF against indicators of intelligence was also calculated. Convergent validity of indicators of intelligence (Raven's matrices, vocabulary test) was good (rxtyt = 0.727; R2 = 0.53). Convergent validity of fluency indicators of EF against executive cognition as indicated by performance on the Wisconsin Card Sorting Test was poor (0.087 ≤ rxtyt ≤ 0.304; 0.008 ≤ R2 ≤ 0.092). Discriminant validity of indicators of EF against indicators of intelligence was good (0.106 ≤ rxtyt ≤ 0.548; 0.011 ≤ R2 ≤ 0.300). Our conclusions from these data are clear-cut: apparently dissimilar indicators of intelligence converge on general intellectual ability. Apparently dissimilar indicators of EF (mental fluency, executive cognition) do not converge on general executive ability. Executive abilities, although non-unitary, can be reasonably well distinguished from intellectual ability. The present data contribute to the hitherto meager evidence base regarding the validity of popular indicators of EF.

An event-related brain potential study of auditory attention in cochlear implant users.

OBJECTIVE: Cochlear implants (CIs) provide access to the auditory world for deaf individuals. We investigated whether CIs enforce attentional alterations of auditory cortical processing in post-lingually deafened CI users compared to normal-hearing (NH) controls. METHODS: Event-related potentials (ERPs) were recorded in 40 post-lingually deafened CI users and in a group of 40 NH controls using an auditory three-stimulus oddball task, which included frequent standard tones (Standards) and infrequent deviant tones (Targets), as well as infrequently occurring unique sounds (Novels). Participants were exposed twice to the three-stimulus oddball task, once under the instruction to ignore the stimuli (ignore condition), and once under the instruction to respond to infrequently occurring deviant tones (attend condition). RESULTS: The allocation of attention to auditory oddball stimuli exerted stronger effects on N1 amplitudes at posterior electrodes in response to Standards and to Targets in CI users than in NH controls. Other ERP amplitudes showed similar attentional modulations in both groups (P2 in response to Standards, N2 in response to Targets and Novels, P3 in response to Targets). We also observed a statistical trend for an attenuated attentional modulation of Novelty P3 amplitudes in CI users compared to NH controls. CONCLUSIONS: ERP correlates of enhanced CI-mediated auditory attention are confined to the latency range of the auditory N1, suggesting that enhanced attentional modulation during auditory stimulus discrimination occurs primarily in associative auditory cortices of CI users. SIGNIFICANCE: The present ERP data support the hypothesis of attentional alterations of auditory cortical processing in CI users. These findings may be of clinical relevance for the CI rehabilitation.

The Wisconsin Card Sorting Test: Split-Half Reliability Estimates for a Self-Administered Computerized Variant.

Self-administered computerized assessment has the potential to increase the reach of neuropsychological assessment. The present study reports the first split-half reliability estimates for a self-administered computerized variant of the Wisconsin Card Sorting Test (WCST), which is considered as a gold standard for the neuropsychological assessment of executive functions. We analyzed data from a large sample of young volunteers (N = 375). Split-half reliability estimates for perseveration errors, set-loss errors, and inference errors were all above 0.90. Split-half reliability estimates for response time measures on switch and repeat trials exceeded 0.95. Our results indicated sufficient split-half reliability for a self-administered computerized WCST, paving the way for an advanced digital assessment of executive functions. We discuss potential effects of test formats, administration variants, and sample characteristics on split-half reliability.

Electroencephalographic correlates of temporal Bayesian belief updating and surprise.

The brain predicts the timing of forthcoming events to optimize responses to them. Temporal predictions have been formalized in terms of the hazard function, which integrates prior beliefs on the likely timing of stimulus occurrence with information conveyed by the passage of time. However, how the human brain updates prior temporal beliefs is still elusive. Here we investigated electroencephalographic (EEG) signatures associated with Bayes-optimal updating of temporal beliefs. Given that updating usually occurs in response to surprising events, we sought to disentangle EEG correlates of updating from those associated with surprise. Twenty-six participants performed a temporal foreperiod task, which comprised a subset of surprising events not eliciting updating. EEG data were analyzed through a regression-based massive approach in the electrode and source space. Distinct late positive, centro-parietally distributed, event-related potentials (ERPs) were associated with surprise and belief updating in the electrode space. While surprise modulated the commonly observed P3b, updating was associated with a later and more sustained P3b-like waveform deflection. Results from source analyses revealed that neural encoding of surprise comprises neural activity in the cingulo-opercular network (CON) and parietal regions. These data provide evidence that temporal predictions are computed in a Bayesian manner, and that this is reflected in P3 modulations, akin to other cognitive domains. Overall, our study revealed that analyzing P3 modulations provides an important window into the Bayesian brain. Data and scripts are shared on OSF: https://osf.io/ckqa5/.

Botulinum toxin dosing in arm muscles: contextual factors.

Botulinum toxin (BT) has been successfully used for many years to treat various muscle hyperactivity disorders including dystonia and spasticity. Its dosing is guided by dosing tables describing target muscles and dose ranges. To refine the BT dosing, we wanted to analyse how contextual factors may influence the injector's final dosing decision.In a retrospective review of real-life data of 1170 BT treatments, we studied the influence of various contextual factors on the BT doses in 21 arm muscles of 252 patients receiving BT therapy for different muscle hyperactivity disorders.We found that BT arm doses are significantly higher in treatment of spasticity than in treatment of dystonia. We also found that spontaneous arm dystonia requires higher BT doses in a proximal application pattern, whereas task specific writer's cramp requires considerably reduced BT doses with a distal application pattern. Injections of non-arm muscles influence the BT dosing in arm muscles only marginally.Our study demonstrates that BT dosing does not only depend on the particularities of the individual target muscle injected, such as its volume and its static or phasic function. BT dosing and its application pattern rather depend on additional contextual factors such as the aetiology and pathophysiology of the muscle hyperactivity treated. These contextual factors need to be included in dosing tables and may improve the outcome of BT therapy.

The Reliability of the Wisconsin Card Sorting Test in Clinical Practice.

The Wisconsin Card Sorting Test (WCST) represents the gold standard for the neuropsychological assessment of executive function. However, very little is known about its reliability. In the current study, 146 neurological inpatients received the Modified WCST (M-WCST). Four basic measures (number of correct sorts, categories, perseverative errors, set-loss errors) and their composites were evaluated for split-half reliability. The reliability estimates of the number of correct sorts, categories, and perseverative errors fell into the desirable range (rel ≥ .90). The study therefore disclosed sufficiently reliable M-WCST measures, fostering the application of this eminent psychological test to neuropsychological assessment. Our data also revealed that the M-WCST possesses substantially better psychometric properties than would be expected from previous studies of WCST test-retest reliabilities obtained from non-patient samples. Our study of split-half reliabilities from discretionary construed and from randomly built M-WCST splits exemplifies a novel approach to the psychometric foundation of neuropsychology.

Cognitive Performance of Patients with Adult 5q-Spinal Muscular Atrophy and with Amyotrophic Lateral Sclerosis.

Motor neuron diseases, such as spinal muscular atrophy (SMA) and amyotrophic lateral sclerosis (ALS), share several clinical similarities while differing substantially in etiology, disease onset and progression. Cognitive dysfunction, a clinically relevant non-motor feature in a substantial proportion of ALS patients, has been less frequently investigated in SMA. In this prospective multicenter cross-sectional study, cognitive function was assessed by the Edinburgh Cognitive (and Behavioural) ALS Screen (ECAS) and a German vocabulary test (Wortschatztest, WST) in 34 adult patients with SMA types 2-4 and in 34 patients with ALS. Demographic and clinical parameters were assessed to identify factors that potentially influence cognitive function. While SMA and ALS patients were comparable in the vocabulary test, on average, SMA patients performed better than ALS patients in the cognitive domains of memory, language and executive function. Better cognitive abilities in SMA patients seemed to be related to the early onset, rather than the extent or the duration, of their physical handicap. Future studies should focus on disease-specific cognitive functions in SMA.

Toward a Computational Neuropsychology of Cognitive Flexibility.

Cognitive inflexibility is a well-documented, yet non-specific corollary of many neurological diseases. Computational modeling of covert cognitive processes supporting cognitive flexibility may provide progress toward nosologically specific aspects of cognitive inflexibility. We review computational models of the Wisconsin Card Sorting Test (WCST), which represents a gold standard for the clinical assessment of cognitive flexibility. A parallel reinforcement-learning (RL) model provides the best conceptualization of individual trial-by-trial WCST responses among all models considered. Clinical applications of the parallel RL model suggest that patients with Parkinson's disease (PD) and patients with amyotrophic lateral sclerosis (ALS) share a non-specific covert cognitive symptom: bradyphrenia. Impaired stimulus-response learning appears to occur specifically in patients with PD, whereas haphazard responding seems to occur specifically in patients with ALS. Computational modeling hence possesses the potential to reveal nosologically specific profiles of covert cognitive symptoms, which remain undetectable by traditionally applied behavioral methods. The present review exemplifies how computational neuropsychology may advance the assessment of cognitive flexibility. We discuss implications for neuropsychological assessment and directions for future research.

Dopaminergic modulation of novelty repetition in Parkinson's disease: A study of P3 event-related brain potentials.

OBJECTIVE: Parkinson's Disease (PD) is a neurodegenerative disease caused by the loss of dopaminergic neurons. Cognitive impairments have been reported using the event-related potential (ERP) technique. Patients show reduced novelty P3 (nP3) amplitudes in oddball experiments, a response to infrequent, surprising stimuli, linked to the orienting response of the brain. The nP3 is thought to depend on dopaminergic neuronal pathways though the effect of dopaminergic medication in PD has not yet been investigated. METHODS: Twenty-two patients with PD were examined "on" and "off" their regular dopaminergic medication in a novelty 3-stimulus-oddball task. Thirty-four healthy controls were also examined over two sessions, but received no medication. P3 amplitudes were compared throughout experimental conditions. RESULTS: All participants showed sizeable novelty difference ERP effects, i.e. ndP3 amplitudes, during both testing sessions. An interaction of diagnosis, medication and testing order was also found, indicating that dopaminergic medication modulated ndP3 in patients with PD across the two testing sessions: We observed enhanced ndP3 amplitudes from PD patients who were off medication on the second testing session. CONCLUSION: Patients with PD 'off' medication showed ERP evidence for repetition-related enhancement of novelty responses. Dopamine depletion in neuronal pathways that are affected by mid-stage PD possibly accounts for this modulation of novelty processing. SIGNIFICANCE: The data in this study potentially suggest that repetition effects on novelty processing in patients with PD are enhanced by dopaminergic depletion.

Parallel model-based and model-free reinforcement learning for card sorting performance.

The Wisconsin Card Sorting Test (WCST) is considered a gold standard for the assessment of cognitive flexibility. On the WCST, repeating a sorting category following negative feedback is typically treated as indicating reduced cognitive flexibility. Therefore such responses are referred to as 'perseveration' errors. Recent research suggests that the propensity for perseveration errors is modulated by response demands: They occur less frequently when their commitment repeats the previously executed response. Here, we propose parallel reinforcement-learning models of card sorting performance, which assume that card sorting performance can be conceptualized as resulting from model-free reinforcement learning at the level of responses that occurs in parallel with model-based reinforcement learning at the categorical level. We compared parallel reinforcement-learning models with purely model-based reinforcement learning, and with the state-of-the-art attentional-updating model. We analyzed data from 375 participants who completed a computerized WCST. Parallel reinforcement-learning models showed best predictive accuracies for the majority of participants. Only parallel reinforcement-learning models accounted for the modulation of perseveration propensity by response demands. In conclusion, parallel reinforcement-learning models provide a new theoretical perspective on card sorting and it offers a suitable framework for discerning individual differences in latent processes that subserve behavioral flexibility.

A Computational Study of Executive Dysfunction in Amyotrophic Lateral Sclerosis.

Executive dysfunction is a well-documented, yet nonspecific corollary of various neurological diseases and psychiatric disorders. Here, we applied computational modeling of latent cognition for executive control in amyotrophic lateral sclerosis (ALS) patients. We utilized a parallel reinforcement learning model of trial-by-trial Wisconsin Card Sorting Test (WCST) behavior. Eighteen ALS patients and 21 matched healthy control participants were assessed on a computerized variant of the WCST (cWCST). ALS patients showed latent cognitive symptoms, which can be characterized as bradyphrenia and haphazard responding. A comparison with results from a recent computational Parkinson's disease (PD) study (Steinke et al., 2020, J Clin Med) suggests that bradyphrenia represents a disease-nonspecific latent cognitive symptom of ALS and PD patients alike. Haphazard responding seems to be a disease-specific latent cognitive symptom of ALS, whereas impaired stimulus-response learning seems to be a disease-specific latent cognitive symptom of PD. These data were obtained from the careful modeling of trial-by-trial behavior on the cWCST, and they suggest that computational cognitive neuropsychology provides nosologically specific indicators of latent facets of executive dysfunction in ALS (and PD) patients, which remain undiscoverable for traditional behavioral cognitive neuropsychology. We discuss implications for neuropsychological assessment, and we discuss opportunities for confirmatory computational brain imaging studies.

The Effect of Transcutaneous Auricular Vagal Nerve Stimulation (taVNS) on P3 Event-Related Potentials during a Bayesian Oddball Task.

Transcutaneous auricular Vagal Nerve Stimulation (taVNS) is a non-invasive brain stimulation technique associated with possible modulation of norepinephrinergic (NE) activity. NE is suspected to contribute to generation of the P3 event-related potential. Recent evidence has produced equivocal evidence whether taVNS influences the P3 in healthy individuals during oddball tasks. We examined the effect of taVNS on P3 amplitudes using a novel visual Bayesian oddball task, which presented 200 sequences of three stimuli. The three consecutive stimuli in each sequence are labelled Draw 1, Draw 2 and Draw 3. In total, 47 Subjects completed this visual Bayesian oddball task under randomised sham and active taVNS stimulation in parallel with an electroencephalographic (EEG) recording. We conducted exploratory analyses of the effect of taVNS on P3 amplitudes separately for Draws. We found typical oddball effects on P3 amplitudes at Draws 1 and 2, but not Draw 3. At Draw 2, the oddball effect was enhanced during active compared to sham taVNS stimulation. These data provide evidence that taVNS influences parietal P3 amplitudes under specific circumstances. Only P3 amplitudes at Draw 2 were affected, which may relate to closure of Bayesian inference after Draw 2. Our findings seemingly support previously reported links between taVNS and the NE system.