Variations in Theta/Beta Ratio and Cognitive Performance in Subpopulations of Subjects with ADHD Symptoms: Towards Neuropsychological Profiling for Patient Subgrouping.

ADHD is a neurodevelopmental disorder appearing in childhood but remaining in many cases in adults. There are both pharmacological and non-pharmacological approaches to treating ADHD, but they do not have the same efficacy in all subjects. Better knowledge of the neurophysiological basis of this disorder will allow for the design of more effective treatments.

Conflict Test Battery for Studying the Act of Facing Threats in Pursuit of Rewards.

Survival depends on the ability of animals to avoid threats and approach rewards. Traditionally, these two opposing motivational systems have been studied separately. In nature, however, they regularly compete for the control of behavior.

Reimplantable Microdrive for Long-Term Chronic Extracellular Recordings in Freely Moving Rats.

Extracellular recordings of electrical activity in freely moving rats are fundamental to understand brain function in health and disease. Such recordings require a small-size, lightweight device that includes movable electrodes (microdrive) to record either a new set of neurons every day or the same set of neurons over time. Ideally, microdrives should be easy to implant, allowing precise and smooth displacement of electrodes.

Hazardous alcohol consumption and risk of alcohol dependence present different neurophysiological correlates.

Introduction: Hazardous alcohol consumption (HAC) is a pattern of alcohol use that may result in harm for the user and/or for those around them. Prior research has suggested that HAC and alcohol dependence share some neurophysiological features but differ in others.

Aim: To determine whether HAC and alcohol dependence presented different neurophysiological correlates.

Recurrent moderate hypoglycemia exacerbates oxidative damage and neuronal death leading to cognitive dysfunction after the hypoglycemic coma.

Moderate recurrent hypoglycemia (RH) is frequent in Type 1 diabetes mellitus (TIDM) patients who are under intensive insulin therapy increasing the risk for severe hypoglycemia (SH). The consequences of RH are not well understood and its repercussions on neuronal damage and cognitive function after a subsequent episode of SH have been poorly investigated. In the current study, we have addressed this question and observed that previous RH during seven consecutive days exacerbated oxidative damage and neuronal death induced by a subsequent episode of SH accompanied by a short period of coma, in the parietal cortex, the striatum and mainly in the hippocampus.

Choice Behavior Guided by Learned, But Not Innate, Taste Aversion Recruits the Orbitofrontal Cortex.

Unlabelled: The ability to select an appropriate behavioral response guided by previous emotional experiences is critical for survival. Although much is known about brain mechanisms underlying emotional associations, little is known about how these associations guide behavior when several choices are available. To address this, we performed local pharmacological inactivations of several cortical regions before retrieval of an aversive memory in choice-based versus no-choice-based conditioned taste aversion (CTA) tasks in rats.

Quantitative electroencephalography analysis in university students with hazardous alcohol consumption, but not alcohol dependence.

Hazardous alcohol consumption is a pattern of consumption that leads to a higher risk of harmful consequences either for the user or for others. This pattern of alcohol consumption has been linked to risky behaviors, accidents, and injuries. Individuals with hazardous alcohol consumption do not necessarily present alcohol dependence; thus, a study of particular neurophysiological correlates of this alcohol consumption pattern needs to be carried out in nondependent individuals.

Effects of glutamate and its metabotropic receptors class 1 antagonist in appetitive taste memory formation.

Cortical glutamatergic activity is known to be important for memory formation in different learning tasks. For example, glutamate activity in the insular cortex plays an important role in aversive taste memory formation by signaling the unconditioned stimulus. However, the role of glutamate in the insular cortex in appetitive taste learning has remained poorly studied.

Taste memory formation: latest advances and challenges.

Taste memory has been a useful model for studying memory formation; using different approaches ranging from lesion studies, analysis of receptor and neurotransmitter activity, and measurement of intracellular signaling mechanisms or gene expression, it has been possible to describe processes which may be involved in several types of memory. Taste memory includes the recognition of a taste as well as its characteristics related to the hedonic value, degree of familiarity, and the nutritive or toxic properties associated with that taste. In terms of evolutionary adaptation, taste memory is necessary for the proper identification of available nutritive foods and, of course, is essential to avoid deadly toxins.

Deficits in aversive but not in safe taste memory in the APPswe/PS1dE9 mice.

Age-related changes in taste memory were evaluated in APPswe/PS1dE9 transgenic (Tg) mice and age-matched wild type littermate controls (Wt). These Tg mice produce increasing amounts of amyloid-beta in the brain with age, develop significant amounts of plaques by 9 months of age, and provide an opportunity to study the effects of Alzheimer's disease-like amyloidosis on different aspects of taste memory. In groups of mice ranging from 15-16 months of age, the neophobic response and its attenuation were similar in Tg and Wt mice.

Safe taste memory consolidation is disrupted by a protein synthesis inhibitor in the nucleus accumbens shell.

Consolidation is the process by which a new memory is stabilized over time, and is dependent on de novo protein synthesis. A useful model for studying memory formation is gustatory memory, a type of memory in which a novel taste may become either safe by not being followed by negative consequences (attenuation of neophobia, AN), or aversive by being followed by post-digestive malaise (conditioned taste aversion, CTA). Here we evaluated the effects of the administration of a protein synthesis inhibitor in the nucleus accumbens (NAc) shell for either safe or aversive taste memory trace consolidation.

Taste memory formation: role of nucleus accumbens.

When a novel taste has been associated with postingestive malaise, animals recognize this taste as aversive. This associative learning is known as conditioned taste aversion. However, when an animal consumes a novel taste and no aversive consequences follow, it becomes recognized as a safe signal, leading to an increase in its consumption in subsequent presentations.

NMDA and muscarinic receptors of the nucleus accumbens have differential effects on taste memory formation.

Animals recognize a taste cue as aversive when it has been associated with post-ingestive malaise; this associative learning is known as conditioned taste aversion (CTA). When an animal consumes a new taste and no negative consequences follow, it becomes recognized as a safe signal, leading to an increase in its consumption in subsequent presentations (attenuation of neophobia, AN). It has been shown that the nucleus accumbens (NAcc) has an important role in taste learning.

Molecular signals into the insular cortex and amygdala during aversive gustatory memory formation.

In this paper, we will provide evidence of the putative molecular signals and biochemical events that mediate the formation of long-lasting gustatory memory trace. When an animal drinks a novel taste (the conditioned stimulus; CS) and it is later associated with malaise (unconditioned stimulus; US), the animal will reject it in the next presentation, developing a long-lasting taste aversion, i.e.

Role of cholinergic system on the construction of memories: taste memory encoding.

There is a large body of evidence suggesting that cholinergic activity is involved in memory processes. It seems that cholinergic activity is essential to learn several tasks and recent works suggest that acetylcholine plays an important role during the early stages of memory formation. In this review, we will discuss the results related to taste memory formation, focusing particularly on the conditioned taste aversion paradigm.

The role of cortical cholinergic pre- and post-synaptic receptors in taste memory formation.

A number of studies have implicated cholinergic activity in the mediation of learning and memory processes. However, the specific role of muscarinic receptors in memory formation mechanisms is less known. The aim of the present study is to evaluate the effects of muscarinic antagonist M2 presynaptic receptor, AFDX-116 (0.

Differential effects of bicuculline and muscimol microinjections into the nucleus basalis magnocellularis in taste and place aversive memory formation.

The role of the nucleus basalis magnocellularis (NBM) in learning and memory has been demonstrated in different learning paradigms such as conditioned taste aversion (CTA) and inhibitory avoidance (IA). This participation has been related to the cholinergic system, but recent studies have reported the potential role of other neurotransmitters such as GABA. The effects of acute intracerebral administration of the GABAergic antagonist bicuculline (0.

Glutamatergic activity in the amygdala signals visceral input during taste memory formation.

Conditioned taste aversion (CTA) is a learning paradigm in which an animal avoids a taste (conditioned stimulus) previously associated with visceral toxic effects [or unconditioned stimulus (US)]. Although many studies have implicated glutamate-mediated neurotransmission in memory consolidation of different types of learning tasks, including CTA, the exact role of this neurotransmitter system in memory formation is not known. Thus, we set out to determine whether glutamate mediates signaling of the US in CTA.

Cortical cholinergic activity is related to the novelty of the stimulus.

A number of studies have related cholinergic activity to the mediation of learning and memory. However, the acetylcholine (ACh) participation has been recently implicated in the early stages of memory formation but not during retrieval. The aim of the present study is to evaluate ACh release in the insular cortex (IC) during presentation of different taste stimuli and during their re-exposition by means of the free-moving microdialysis technique.