Vision: how to train visual cortex to predict reward time.

Little is known about how the brain learns to anticipate the timing of reward. A new study demonstrates that optogenetic activation of basal forebrain input is sufficient to train reward timing activity in the primary visual cortex

A Mathematical Framework for Statistical Decision Confidence

Decision confidence is a forecast about the probability that a decision will be correct. From a statistical perspective, decision confidence can be defined as the Bayesian posterior probability that the chosen option is correct based on the evidence contributing to it. Here, we used this formal definition as a starting point to develop a normative statistical framework for decision confidence. Our goal was to make general predictions that do not depend on the structure of the noise or a specific algorithm for estimating confidence. We analytically proved several interrelations between statistical decision confidence and observable decision measures, such as evidence discriminability, choice, and accuracy. These interrelationships specify necessary signatures of decision confidence in terms of externally quantifiable variables that can be empirically tested. Our results lay the foundations for a mathematically rigorous treatment of decision confidence that can lead to a common framework for understanding confidence across different research domains, from human and animal behavior to neural representations

Signatures of a Statistical Computation in the Human Sense of Confidence

Human confidence judgments are thought to originate from metacognitive processes that provide a subjective assessment about one's beliefs. Alternatively, confidence is framed in mathematics as an objective statistical quantity: the probability that a chosen hypothesis is correct. Despite similar terminology, it remains unclear whether the subjective feeling of confidence is related to the objective, statistical computation of confidence. To address this, we collected confidence reports from humans performing perceptual and knowledge-based psychometric decision tasks. We observed two counterintuitive patterns relating confidence to choice and evidence: apparent overconfidence in choices based on uninformative evidence, and decreasing confidence with increasing evidence strength for erroneous choices. We show that these patterns lawfully arise from statistical confidence, and therefore occur even for perfectly calibrated confidence measures. Furthermore, statistical confidence quantitatively accounted for human confidence in our tasks without necessitating heuristic operations. Accordingly, we suggest that the human feeling of confidence originates from a mental computation of statistical confidence

Navigating the Statistical Minefield of Model Selection and Clustering in Neuroscience

Model selection is often implicit: when performing an ANOVA, one assumes that the normal distribution is a good model of the data; fitting a tuning curve implies that an additive and a multiplicative scaler describes the behavior of the neuron; even calculating an average implicitly assumes that the data were sampled from a distribution that has a finite first statistical moment: the mean. Model selection may be explicit, when the aim is to test whether one model provides a better description of the data than a competing one. As a special case, clustering algorithms identify groups with similar properties within the data. They are widely used from spike sorting to cell type identification to gene expression analysis. We discuss model selection and clustering techniques from a statistician's point of view, revealing the assumptions behind, and the logic that governs the various approaches. We also showcase important neuroscience applications and provide suggestions how neuroscientists could put model selection algorithms to best use as well as what mistakes should be avoided

Differential recruitment of ventral pallidal e-types by behaviorally salient stimuli during Pavlovian conditioning

The ventral pallidum (VP) is interfacing striatopallidal and limbic circuits, conveying information about salience and valence crucial to adjusting behavior. However, how VP neuron populations with distinct electrophysiological properties (e-types) represent these variables is not fully understood. Therefore, we trained mice on probabilistic Pavlovian conditioning while recording the activity of VP neurons. Many VP neurons responded to punishment (54%), reward (48%), and outcome-predicting auditory stimuli (32%), increasingly differentiating distinct outcome probabilities through learning. We identified e-types based on the presence of bursts or fast rhythmic discharges and found that non-bursting, non-rhythmic neurons were the most sensitive to reward and punishment. Some neurons exhibited distinct responses of their bursts and single spikes, suggesting a multiplexed coding scheme in the VP. Finally, we demonstrate synchronously firing neuron assemblies, particularly responsive to reinforcing stimuli. These results suggest that electrophysiologically defined e-types of the VP differentially participate in transmitting reinforcement signals during learning. © 2021 The Author(s

Dual-Transmitter Systems Regulating Arousal, Attention, Learning and Memory

An array of neuromodulators, including monoamines and neuropeptides, regulate most behavioural and physiological traits. In the past decade, dramatic progress has been made in mapping neuromodulatory circuits, in analysing circuit dynamics, and interrogating circuit function using pharmacogenetic, optogenetic and imaging methods This review will focus on several distinct neural networks (acetylcholine/GABA/glutamate; histamine/GABA; orexin/glutamate; and relaxin-3/GABA) that originate from neural hubs that regulate wakefulness and related attentional and cognitive processes, and highlight approaches that have identified dual transmitter roles in these behavioural functions. Modulation of these different neural networks might be effective treatments of diseases related to arousal/sleep dysfunction and of cognitive dysfunction in psychiatric and neurodegenerative disorders

Serdülők és fiatal felnőttek identitása az önértékelés és a társas támogatás függvényében

One is the most important function of identity is beside the role in self-determination process,  how ones person behave in interpersonal and social context (Baumeister, 1986). During the identity forming process the role of reference groups and significant others become to increrase. Their social support as psychosocial resources could promote the identity forming process (Kaplan, Cassel, & Gore, 1977). The identity in adolescence could influence young people future orientation, self-esteem, and could determine the attitudes towards social contexts (Szabó, 2010). The aim of the reseach is one hand to determine the identity status of 9-10th grade adolescents and 1st year BA students, and second hand to explore the relationship between identity status, self –esteem and perceived social support. Subjects had to fill in Rosenberg Self Esteem Scale (Sallay, Martos, Földvári, Szabó & Ittzés, 2014), EOM-EIS-II- Interpersonal Subscale (Bennion & Adams, 1986, in hungarian Biegelbauer, 2003; Szabó, 2003) and Multidimensional Perceived Social Support Scale (Papp- Zipernovszky, Kékesi & Jámbori, 2017). Our results demonstrated that the higher level of self-esteem and the higher level of support from friends and from significant others could promote identity achieving. Controversly identity diffusion correlate with lower level of self-esteem, significantly lower level of social support from friends and significant others. Our study prove convicingly the relevance of self-esteem and social support among adolescents and young adults in identity forming process and to achieve identity.Az identitás a személy önmeghatározásán kívül arra is vonatkozik, hogyan viselkedik az egyén interperszonális vagy szociális kontextusban (Baumeister, 1986).  Az identitás alakítás folyamatában rendkívüli szerepet töltenek be a fiatal életében jelenlévő referencia személyek, jelentős mások, akik által nyújtott társas támogatás, mint pszichoszociális erőforrás támogathatja az identitásalakítás folyamatát (Kaplan, Cassel, & Gore, 1977). A serdülőkori identitás befolyásolja a fiatal jövőképét, önértékelését, meghatározza a társas helyzetekhez való viszonyát is (Szabó, 2010). Kutatásunk célja egyrészről a 9-10. osztályos középiskolás diákok és az elsőéves egyetemisták identitásállapotának feltárása volt, másrészről annak vizsgálata, hogy a különböző identitásállapotok milyen összefüggést mutatnak az önértékeléssel, és a társas támogatás mértékével. A vizsgálati személyek a Rosenberg Önértékelés Skálát (Sallay, Martos, Földvári, Szabó és Ittzés, 2014), az EOM-EIS-II -Interperszonális identitás alskáláját (Bennion és Adams, 1986, magyarul Biegelbauer, 2003; Szabó, 2003), és a Multidimenzionális Társas Támogatás Kérdőívet (Papp- Zipernovszky, Kékesi és Jámbori, 2017) töltötték ki. Vizsgálatunk bebizonyította, hogy mind a serdülők, mind a fiatal felnőttek esetében a magasabb önbizalom és az észlelt társas támogatás, főként a barátok és a jelentős mások tekintetében segíti a valódi identitás állapot elérését. Míg a diffúz identitás alacsonyabb önértékelés pontszámmal, és szignifikánsan alacsonyabb mértékű baráti és jelentős másoktól észlelt támogatással járt együtt. Kutatásunk meggyőzően bizonyítja, hogy az önértékelés és a társas támogatás jelentős szerepet játszik mindkét korosztálynál a valódi identitás állapotának elérésében

Célok, tervek és tanulási stratégiák serdülők és fiatal felnőttek körében

Getting to know how young people think about their future and what factors affect their thinking is essential from the perspective of their success at high school and in higher education. The study aimed at comparing the time perspectives, goal orientations, learning strategies and procrastination behaviors of high school and university students, exploring their relationship to achievement as well as at revealing the underlying connections. The following instruments were used: Time Perspective Inventory (Zimbardo and Boyd, 1999; 2012, in Hungarian: Orosz et.al., 2015); Active Procrastination Scale (Choi and Moran, 2009, in Hungarian: Szabó, 2012); 3 x 2 Achievement Goal Questionnaire (Elliot et.al., 2011, in Hungarian: Urbán et.al., 2014); Learning Strategies Questionnaire (Pintrich et.al., 1991, in Hungarian: D. Molnár, 2013). The psychometric properties of the instruments were found to be satisfactory in both age groups. Present-hedonistic and present-fatalistic time perspectives were more common among high school students, whereas for university students, the future-oriented and the past positive time perspectives were more dominant. Although adaptive goals and learning strategies were more common among university students, they also tended to use less effective learning strategies to memorize information. Task goals seemed to have the strongest relationship to learning-related individual characteristics like the various learning strategy scales or performance satisfaction. Moreover, the analysis of the relationship of goals and time perspectives confirmed that task goals are more adaptive than self goals, as the former had stronger connections to future orientation, which is considered to be a positive characteristic.  A középiskolai és felsőoktatási sikeresség szempontjából lényeges tényező a fiatalok jövőre vonatkozó gondolkodásának, valamint az ezzel összefüggésben álló tényezőknek a megismerése. Vizsgálatunk célja középiskolások és egyetemisták időperspektíváinak, célorientációinak, tanulási stratégiáinak és halogatásának összehasonlítása, továbbá ezek összefüggéseinek, valamint az eredményességgel való kapcsolatuknak a feltárása volt. Kutatásunkban a Zimbardo-féle Rövidített Időperspektíva Kérdőívet (Zimbardo és Boyd, 1999; 2012, magyarul Orosz és mtsai, 2015), az Aktív-passzív halogatás kérdőívet (Choi és Moran, 2009, magyarul Szabó, 2012), a 3×2 Teljesítés-Cél Kérdőívet (Elliot és mtsai, 2011, magyarul Urbán és mtsai, 2014) és a Tanulási stratégiák kérdőívet (Pintrich és mtsai, 1991, magyarul D. Molnár, 2013) használtuk. A mérőeszközök megfelelő pszichometriai jellemzőkkel rendelkeznek mindkét korcsoportban. A középiskolások körében gyakrabban megfigyelhető a jelen hedonista és a jelen fatalista időperspektíva, míg az egyetemisták esetén a jövő-orientált és múlt pozitív orientáció idődimenzió jelent meg határozottabban. Az adaptív célok és tanulási stratégiák követése jellemzőbb a hallgatók körében, ugyanakkor a kevésbé hatékony memorizáló tanulási stratégia követése is erősebb. Elemzéseink szerint a feladat-célok függenek össze a legszorosabban a tanulással kapcsolatba hozható vizsgált egyéni jellemzőkkel, így a tanulási stratégiák egyes skáláival vagy a teljesítménnyel való elégedettséggel. Emellett a célok és az időperspektívák kapcsolatának vizsgálata ugyancsak megerősítette, hogy a feladat-célok adaptívabbak a szelf-céloknál, mivel az előbbiek erősebb összefüggést mutattak az egyértelműen pozitív jellemzőként számon tartott jövő-orientációval

Huygens synchronization of medial septal pacemaker neurons generates hippocampal theta oscillation

Episodic learning and memory retrieval are dependent on hippocampal theta oscillation, thought to rely on the GABAergic network of the medial septum (MS). To test how this network achieves theta synchrony, we recorded MS neurons and hippocampal local field potential simultaneously in anesthetized and awake mice and rats. We show that MS pacemakers synchronize their individual rhythmicity frequencies, akin to coupled pendulum clocks as observed by Huygens. We optogenetically identified them as parvalbumin-expressing GABAergic neurons, while MS glutamatergic neurons provide tonic excitation sufficient to induce theta. In accordance, waxing and waning tonic excitation is sufficient to toggle between theta and non-theta states in a network model of single-compartment inhibitory pacemaker neurons. These results provide experimental and theoretical support to a frequency-synchronization mechanism for pacing hippocampal theta, which may serve as an inspirational prototype for synchronization processes in the central nervous system from Nematoda to Arthropoda to Chordate and Vertebrate phyla

Behavioral, neural and ultrastructural alterations in a graded-dose 6-OHDA mouse model of early-stage Parkinson's disease

Studying animal models furthers our understanding of Parkinson’s disease (PD) pathophysiology by providing tools to investigate detailed molecular, cellular and circuit functions. Different versions of the neurotoxin-based 6-hydroxydopamine (6-OHDA) model of PD have been widely used in rats. However, these models typically assess the result of extensive and definitive dopaminergic lesions that reflect a late stage of PD, leading to a paucity of studies and a consequential gap of knowledge regarding initial stages, in which early interventions would be possible. Additionally, the better availability of genetic tools increasingly shifts the focus of research from rats to mice, but few mouse PD models are available yet. To address these, we characterize here the behavioral, neuronal and ultrastructural features of a graded-dose unilateral, single-injection, striatal 6-OHDA model in mice, focusing on early-stage changes within the first two weeks of lesion induction. We observed early onset, dose-dependent impairments of overall locomotion without substantial deterioration of motor coordination. In accordance, histological evaluation demonstrated a partial, dose-dependent loss of dopaminergic neurons of substantia nigra pars compacta (SNc). Furthermore, electron microscopic analysis revealed degenerative ultrastructural changes in SNc dopaminergic neurons. Our results show that mild ultrastructural and cellular degradation of dopaminergic neurons of the SNc can lead to certain motor deficits shortly after unilateral striatal lesions, suggesting that a unilateral dose-dependent intrastriatal 6-OHDA lesion protocol can serve as a successful model of the early stages of Parkinson’s disease in mice