Bryant J. Jongkees's research while affiliated with Leiden University and other places

Publications (15)

Article
Full-text available
Adaptive goal-directed behavior requires a dynamic balance between maintenance and updating within working memory (WM). This balance is controlled by an input-gating mechanism implemented by dopamine in the basal ganglia. Given that dopaminergic manipulations can modulate performance on WM-related tasks, it is important to gain mechanistic insight...
Article
Full-text available
Transcranial direct current stimulation (tDCS) transiently alters cortical excitability and synaptic plasticity. So far, few studies have investigated the behavioral effects of applying tDCS to the cerebellum. Given the cerebellum’s inhibitory effects on cortical motor areas as well as its role in fine motor control and motor coordination, we inves...
Article
Full-text available
Transcranial direct current stimulation (tDCS) can alter cortical excitability, neural plasticity and cognitive‐behavioral performance, however its effects are known to vary across studies. A partial account of this variability relates to individual differences in dopamine function. Indeed, dopaminergic manipulations alter the physiological and cog...
Article
Full-text available
Transcutaneous vagus nerve stimulation (tVNS) is a non-invasive and safe technique that transiently enhances brain GABA and noradrenaline levels. Although tVNS has been used mainly to treat clinical disorders such as epilepsy, recent studies indicate it is also an effective tool to investigate and potentially enhance the neuromodulation of action c...
Article
Full-text available
The neurovisceral integration model proposes that heart rate variability (HRV) is linked to prefrontal cortex activity via the vagus nerve, which connects the heart and the brain. HRV, an index of cardiac vagal tone, has been found to predict performance on several cognitive control tasks that rely on the prefrontal cortex. However, the link betwee...
Article
One of the most important functions of cognitive control is action cascading: the ability to cope with multiple response options when confronted with various task goals. A recent study implicates a key role for dopamine (DA) in this process, suggesting higher D1 efficiency shifts the action cascading strategy toward a more serial processing mode, w...
Article
Full-text available
Precursors of neurotransmitters are increasingly often investigated as potential, easily-accessible methods of neuromodulation. However, the amino-acid glutamine, precursor to the brain’s main excitatory and inhibitory neurotransmitters glutamate and GABA, remains notably little investigated. The current double-blind, randomized, placebo-controlled...
Article
Background: Transcranial direct current stimulation (tDCS) is an increasingly popular method of modulating cognitive functions in humans. However, some doubt its efficacy as findings are inconsistent or remain unreplicated. It is speculated dopamine (DA) might play an important role in this inconsistency, by determining the direction and strength o...
Article
An extensive body of research suggests the spontaneous eye blink rate (EBR) is a non-invasive indirect marker of central dopamine (DA) function, with higher EBR predicting higher DA function. In the present review we provide a comprehensive overview of this literature. We broadly divide the available research in studies that aim to disentangle the...
Article
Tryptophan (TRP), the precursor of serotonin (5-HT), is one of the most investigated amino-acids. TRP supplementation can increase 5-HT levels in the brain and for this reason numerous studies have investigated whether administration of TRP can positively influence social behavior that relies on serotonergic function. Here we review the available s...
Article
Consuming the amino-acid tyrosine (TYR), the precursor of dopamine (DA) and norepinephrine (NE), may counteract decrements in neurotransmitter function and cognitive performance. However, reports on the effectiveness of TYR supplementation vary considerably, with some studies finding beneficial effects, whereas others do not. Here we review the ava...
Article
Animal studies and research in humans have shown that the supplementation of tyrosine, or tyrosine-containing diets, increase the plasma tyrosine and enhance brain dopamine (DA). However, the strategy of administering tyrosine (and the role of DA therein) to enhance cognition is unclear and heavily debated. We studied, in a healthy population, whet...
Article
Full-text available
In this study we tested the idea that the food supplement l-Tyrosine (TYR) repletes resources required for cognitive-control operations. We investigated whether the "updating" (and monitoring) of working memory (WM) representations, a key cognitive-control function, can be promoted by administering TYR, the biochemical precursor of dopamine. Partic...

Citations

... Given the characterization above of the relation between DA, updating and maintenance, it is predicted that DA levels will follow an inverted-u-shaped association with performance on tasks requiring cognitive control, rather than following a more-is-better principle (Cools & D'Esposito, 2011;Jongkees, 2020). This is so since, as often noted, cognitive control implies achieving a balance between the opposing demands of stable maintenance of task goals in the face of distractors, and their flexible updating when situational demands have changed (e.g., Miyake et al., 2000;Ueltzhöffer et al., 2015). ...
... A total of 138 healthy, Dutch-speaking participants were recruited. Participants were randomly assigned to receive either anodal or sham stimulation with the Belief or Cognitive SRT tasks to avoid any carryover effects of sequence learning (Geiger et al., 2018) or ineffective blinding of brain stimulation (Jongkees et al., 2019). After the experiment, the data from thirty-two participants were excluded. ...
... In a multicenter trial recruiting unipolar and bipolar patients randomized to receive active or sham tDCS sessions, COMT genotype was not associated with the antidepressant effects of tDCS (Martin et al., 2018a). Another negative result comes from a recent study conducted on healthy subjects displaying that the COMT Val 158 Met polymorphism (rs4680) did not impact the beneficial after-effects of prefrontal tDCS on working memory (Jongkees et al., 2019). However, other reports indicate a putative role of COMT genotype in tDCS responses. ...
... This posits tVNS as an excellent candidate to mitigate SAS in a similar way to GCS. Moreover, tVNS has shown to improve cognitive processes directly related to the neuromodulation of motor control (Jongkees et al., 2018;Van Leusden et al., 2015), concentration , cognitive flexibility (Borges et al., 2020) and increase of alertness and associative memory (Raedt et al., 2011;Roosevelt et al., 2006), which are fundamental driving processes. It should be noted that a technique that reduces SAS should not affect driving variables as a side effect, such as GCS, which instead improves them by decreasing SAS symptoms. ...
... Vagus nerve stimulation (VNS) is used for the treatment of several neurological disorders [1][2][3]. Vagal afferents may function as an endogenous mediator of certain cognitive functions [4,5]. Ascending fibers of the vagus nerve innervate the nucleus of the solitary tract, which then relays signals to areas in the brain stem and the forebrain, including areas in the thalamus, amygdala, and hippocampus that are involved in learning and memory [6]. ...
... A second aim of our study relates to performance in color discrimination, which has recently been considered as a proxy for frontal DA (Colzato et al., 2014a;Jongkees, Steenbergen, & Colzato, 2017). Altered color discrimination in the blueyellow axis ('tritan deficit') has been linked to DA-associated pathologies, such as Parkinson's disease (Büttner et al., 1995;Oh et al., 2011;Pieri, Diederich, Raman, & Goetz, 2000), Huntington's disease and Tourette syndrome (Georgiou, Bradshaw, Phillips, Bradshaw, & Chiu, 1995;Melun, Morin, Muise, & DesRosiers, 2001;Paulus et al., 1993), ADHD Kim et al., 2014;Spinelli et al., 2011;Tannock, Banaschewski, & Gold, 2006), and cocaine abuse (Desai, Roy, Roy, Brown, & Smelson, 1997;Hulka, Wagner, Preller, Jenni, & Quednow, 2013;Sellaro, Hommel, & Colzato, 2014). ...
... It's been suggested that a lack of Gln in the muscles might lead to a slower rate of lymphocyte proliferation in response to antigens, compromising immunological protection against viral infection. Intense physical activity may reduce the rate of Gln production from skeletal muscle and/or accelerate the amount of Gln absorption by other Gln-using organs or tissues, reducing Gln availability for immune system cells [16,17]. In figure 3, it represents the mechanism of glutamine as an antifatigue. ...
... There are four indicators that are often used, that is, hits (the accuracy of matching trials), correct rejections (the accuracy of mismatching trials) or false alarms (one minus correct rejections), d prime (d' , hits minus false alarms), and reaction time (e.g., Jongkees et al., 2017). d' was first introduced based on signal detection theory to avoid distorted hits by false alarms (Haatveit et al., 2010). ...
... Previous studies have shown that the eye blink rate (EBR) is related to many cognitive functions. Since EBR is related to dopamine (DA) activity, it predicts many DArelated cognitive performances (Jongkees & Colzato, 2016): cognitive flexibility, attention, and working memory updating (Dang et al., 2016;Zhang et al., 2015). Hence, to explain the results, we aimed to use eye tracking to investigate how cognitive performance influences human perception of time. ...
... In fact, oxytocin appears to lowers the amygdala response to emotional expression irrespective of valence [15]. Homologues of the mammalian oxytocin and vasopressin neuropeptides and their respective target receptors modulate social and reproductive behaviors across bilaterian animals including social behavior, social cognition, and psychiatric phenotypes such as autism spectrum disorder in humans [16]. ...