Background Psychosis has various causes, including mania and schizophrenia. Since the differential diagnosis of psychosis is exclusively based on subjective assessments oral interviews with patients, an objective quantification speech disturbances that characterize schizophrenia in order. In principle, such could be achieved by analysis graphs. A graph represents a network nodes connected edges; graphs, correspond to words edges semantic grammatical relationships. Methodology/Principal...

Deficits in decoding rewarding (and aversive) signals are present several neuropsychiatric conditions such as depression and addiction, emphasising the importance of studying underlying neural circuits detail. One key regions reward circuit is nucleus accumbens (NAc). The classical view on field postulates that NAc dopamine receptor D1-expressing medium spiny neurons (D1-MSNs) convey signals, while D2-expressing MSNs (D2-MSNs) encode aversion. Here, we show both MSN subpopulations can drive...

Since the first measurements of neuronal avalanches, critical brain hypothesis has gained traction. However, if is critical, what phase transition? For several decades, it been known that cerebral cortex operates in a diversity regimes, ranging from highly synchronous states (with higher spiking variability) to desynchronized lower variability). Here, using both new and publicly available data, we test independent signatures criticality show transition occurs an intermediate value...

The nucleus accumbens (NAc) plays a central role in reinforcement and motivation. Around 95% of the NAc neurons are medium spiny (MSNs), divided into those expressing dopamine receptor D1 (D1R) or D2 (D2R). Optogenetic activation D2-MSNs increased motivation, whereas inhibition these produced opposite effect. Yet, it is still unclear how affects other local neurons/interneurons input terminals this contributes for motivation enhancement. To answer question, work we combined optogenetic...

The nucleus accumbens (NAc) is a key region in motivated behaviors. NAc medium spiny neurons (MSNs) are divided into those expressing dopamine receptor D1 or D2. Classically, D1- and D2-MSNs have been described as having opposing roles reinforcement, but recent evidence suggests more complex role for D2-MSNs. Here, we show that optogenetic modulation of D2-MSN to ventral pallidum (VP) projections during different stages behavior has contrasting effects motivation. Activation D2-MSN-VP...

Cortical areas that directly receive sensory inputs from the thalamus were long thought to be exclusively dedicated a single modality, originating separate labeled lines. In past decade, however, several independent lines of research have demonstrated cross-modal responses in primary areas. To investigate whether these represent behaviorally relevant information, we carried out neuronal recordings somatosensory cortex (S1) and visual (V1) rats as they performed whisker-based tasks dark....

Recent experimental results on spike avalanches measured in the urethane-anesthetized rat cortex have revealed scaling relations that indicate a phase transition at specific level of cortical firing rate variability. The point to critical exponents whose values differ from those branching process, which has been canonical model employed understand brain criticality. This suggested different model, with transition, might be required explain data. Here we show this is not necessarily case. By...

The laterodorsal tegmentum (LDT) is associated with reward considering that it modulates VTA neuronal activity, but recent anatomical evidence shows the LDT also directly projects to nucleus accumbens (NAc). We show majority of LDT-NAc inputs are cholinergic, there GABAergic and glutamatergic innervation; activation induces a predominantly excitatory response in NAc. Non-selective optogenetic projections rats enhances motivational drive shifts preference an otherwise equal reward; whereas...

Hebb proposed that synapses between neurons fire synchronously are strengthened, forming cell assemblies and phase sequences. The former, on a shorter scale, ensembles of synchronized cells function transiently as closed processing system; the latter, larger correspond to sequential activation able represent percepts behaviors. Nowadays, recording large neuronal populations allows for detection multiple assemblies. Within Hebb’s theory, next logical step is analysis Here we detected...

Since the first measurements of neuronal avalanches [1], critical brain hypothesis has gained traction [2]. However, if is critical, what phase transition? For several decades it been known that cerebral cortex operates in a diversity regimes [3], ranging from highly synchronous states (e.g. slow wave sleep [4], with higher spiking variability) to desynchronized alert waking [5], lower variability). Here, using independent signatures criticality, we show transition occurs an intermediate...

Ventral tegmental area (VTA) activity is critical for reward/reinforcement and tightly modulated by the laterodorsal tegmentum (LDT). In utero exposure to glucocorticoids (iuGC) triggers prominent motivation deficits but nothing known about impact of this in LDT-VTA circuit. We show that iuGC-rats have long-lasting changes cholinergic markers LDT, together with a decrease LDT basal neuronal activity. Interestingly, upon stimulation, iuGC animals present magnitude excitation an increase VTA...

The presumed proximity to a critical point is believed endow the brain with scale-invariant statistics, which are thought confer various functional advantages in terms of its information processing, storage, and transmission capabilities. To assess relationship between scaling cortical states, we apply phenomenological renormalization group analysis 3-h spiking data recordings from urethane-anesthetized rat's visual cortex. Under this type anesthesia, states dynamically shift across spectrum...

A correction to this paper has been published and can be accessed via a link at the top of paper.

It has recently been reported that statistical signatures of brain criticality, obtained from distributions neuronal avalanches, can depend on the cortical state. We revisit these claims with a completely different and independent approach, employing maximum entropy model to test whether criticality appear in urethane-anesthetized rats. To account for spontaneous variation states, we parse time series perform analysis as function variability population spiking activity. compare data sets...

Abstract The cerebral cortex is an anatomically divided and functionally specialized structure. It includes distinct areas, which work on different states over time. structural features of spiking activity in sensory cortices have been characterized during spontaneous evoked activity. However, the coordination among cortical sub-cortical neurons across remains poorly characterized. We addressed this issue by studying temporal coupling variability recorded from primary hippocampus...

A major frontier in neuroscience is to find neural correlates of perception, learning, decision making, and a variety other types behavior. In the last decades, modern devices allow simultaneous recordings different operant responses electrical activity large neuronal populations. However, commercially available instruments for studying conditioning are expensive, design low-cost chambers has emerged as an appealing alternative resource-limited laboratories engaged animal this article, we...

The local field potential (LFP) is as a measure of the combined activity neurons within region brain tissue. While biophysical modeling schemes for LFP in cortical circuits are well established, there paramount lack understanding regarding properties along states assumed over long periods. Here we use symbolic information approach to determine statistical complexity based on Jensen disequilibrium and Shannon entropy data recorded from primary visual cortex (V1) urethane-anesthetized rats...

This study focuses on understanding visual coding in multiple brain areas and its implications for neural processing the system. It highlights use of simultaneous recordings large neuronal populations to inves tigate how information is encoded processed brain. By studying activity areas, paper aims uncover mechanisms underlying brain-wide perception provide insights into basis processing. The findings this research contribute broader field neuroscience have disorders developing therapeutic...

The critical brain hypothesis posits that neural systems operate near a phase transition, optimising the transmission, storage, and processing of information. While scale invariance non-Gaussian dynamics - hallmarks criticality have been observed in activity, direct link between behavioural performance remains unexplored. Here, we use phenomenological renormalisation group (PRG) approach to examine neuronal activity primary visual cortex mice performing recognition task. We show non-trivial...

This paper describes the fabrication of silicon neural probes based on low-cost semiconductor technologies, such as photolithography, thin-films deposition and blade dicing. Each 8 mm long fabricated probe has 13 platinum recording sites (microelectrodes) with different dimensions, ranging from 50 × μm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> to 300 . The microelectrodes impedance were characterized through electrochemical...

The local field potential (LFP) is as a measure of the combined activity neurons within region brain tissue. While biophysical modeling schemes for LFP in cortical circuits are well established, there paramount lack understanding regarding properties along states assumed over long periods. Here we use symbolic information approach to determine statistical complexity based on Jensen disequilibrium and Shannon entropy data recorded from primary visual cortex (V1) urethane-anesthetized rats...