S6 – Neural activity and behavior in vertebrates: the spark that moves us

The study of neural electrical activity is a powerful tool in our attempt to understand the brain circuits involved in a certain behavior. It is within these neural circuits that the essence of behavior is encoded, where thoughts are formed, decisions are made, and actions are executed. By deciphering how neural activity encodes information and the areas involved, we gain unprecedented insight into the evolutionary conserved mechanisms that govern behavior in vertebrates, from the simplest primitive behaviors to the most complex cognitive processes.
The symposium will have four talks addressing different vertebrate models were the electrical neural activity is used to identify the brain areas involved in a selected group highly relevant behaviours: sleep, emotional responses and consciousness.

The study of how individuals modify their behavior in response to new reinforcement conditions is crucial for understanding cognitive and emotional processes in adapting to changing environments. The Successive Negative Contrast (CNS) paradigm allows for the investigation of these processes in a laboratory setting by training subjects under high reinforcement conditions that are unexpectedly degraded, leading to behavioral and physiological changes known as “frustration response”. Understanding which brain areas participate in incentive evaluation and negative responses like frustration is fundamental. In this study, two techniques were used to investigate the neural basis of the phenomenon: (i) Electrophysiological recordings in the medial prefrontal cortex during a CNS protocol with rats in head-fixed conditions receiving devaluation of sugary solutions. An increase in firing rate of pyramidal neurons was observed following devaluation, along with changes in their response pattern. (ii) Immunohistochemistry of c-Fos in the medial prefrontal cortex in subjects receiving devaluation of solid food. An increase in anterior cingulate cortex activity was observed in devalued subjects compared to non-devalued subjects. These findings will contribute to characterizing the circuits involved in frustration response, shedding light on the neurobiological underpinnings of adaptive behavior in response to changing reinforcement contingencies.

Rocío C. Fernández
roccfernandez@gmail.com
Grupo de Aprendizaje y Cognición Comparada y Grupo de Circuitos Neuronales, Cognición y Conducta, Lab de Biología del Comportamiento, IBYME-CONICET Instituto de Investigaciones, Facultad de Psicología, UBA
https://ibyme.org.ar/investigacion/laboratorios/biologia-del-comportamiento/

In all female mammals studied, the mother will experience sleep disturbances during the postpartum period. However, sleep deprivation (SD) is a common feature in modern society that will worsen maternal sleep. Although it is widely documented that SD in non-lactating animals determines a wide variety of physiological alterations, its effects during the postpartum period it is understudied. Being SD a stressful situation itself, together with the fact that stress in mother can modify milk ejection and composition, and maternal behavior, we wonder if these parameters would be disrupted when mother rats are subjected to an additional sleep restriction to the already existing sleep disturbances. For that purpose, lactating rats were implanted for polysomnographic recordings and for deep brain electrical stimulation for SD procedure. Mother rats were randomly assigned to a control group, chronic SD or acute SD; maternal behavior, milk ejections, and milk macronutrients components were analyzed.
Our results show that the consequences of acute and chronic SD differ, where acute SD mainly affects macronutrient composition and chronic SD alters active maternal behaviors towards the end of the SD period.

Luciana Benedetto
lbenedet@fmed.edu.uy
Unidad Académica de Fisiología, Facultad de Medicina, UdelaR
http://www.labsueno.fmed.edu.uy/material-estudiantes/materiales/l%C3%ADneas-investigaci%C3%B3n

Sleep constitutes a quiescent state that is crucially involved in brain plasticity and vital for health. However, besides our need to sleep, we also need to eat, mate, move or interact with other conspecifics. The coordination of these active behaviors during vigilance is crucial to ensure appropriate time to rest. Animals do not just fall asleep at any time and anywhere: prior to sleep, they find an appropriate site and engage in a stereotypic behavioral routine that may involve preparing a nest or a bed, performing hygiene related activities, sometimes in the companionship of other conspecifics. Recently, in our lab we determined that mice perform a stereotypic routine before sleep that involves self-grooming and nest-building behavior. Moreover, we found that a glutamatergic population of neurons in the lateral hypothalamus is key for the appropriate development of nesting behavior and that this influences the quality of sleep. Notably, we also found that this routine is performed next to other conspecific mice that sleep in the same nest and who later on share synchronized sleep features. Our work opens new avenues to study plasticity in sleep and highlights the importance of the presleep routine in achieving sleep consolidation. Our current work is focusing on how sleep and the sleep preparatory routine may be altered under emotional distress, impeding the normal balance between vigilance and sleep.

Maria Ines Sotelo
minessotelo@gmail.com
Grupo de Aprendizaje y Cognición Comparada, Lab de Biología del Comportamiento, IBYME-CONICET Instituto de Investigaciones, Facultad de Psicología, UBA
https://ibyme.org.ar/investigacion/laboratorios/biologia-del-comportamiento/

Consciousness is one of the most complex aspects of human experience. Studying the mechanisms involved in the transitions among different levels of consciousness remains as one of the greatest challenges in neuroscience. In this study we use a measure of integrated information (ΦAR) to evaluate dynamic changes during consciousness transitions. We applied the measure to intracranial electroencephalography (SEEG) recordings collected from 6 patients that suffer from refractory epilepsy, taking into account inter-ictal, pre-ictal and ictal periods. We analyzed the dynamical evolution of ΦAR in groups of electrode contacts outside the epileptogenic region and compared it with the Consciousness Seizure Scale (CCS). We show that changes on ΦAR are significantly correlated with changes in the reported states of consciousness.

Sergio Lew
sergiolew@gmail.com
Instituto de Ingeniería Biomédica, Facultad de Ingeniería, UBA
https://www.fi.uba.ar/institucional/institutos-centros-y-escuelas/instituto-de-ingenieria-biomedica