Slider Image: 
Lname: 
Sobel
Fname: 
Noam
Homepage: 
http://www.weizmann.ac.il/neurobiology/worg
Research title: 
Olfactory fingerprints
Research topic: 

Active Sensing and Motor-Sensory Loops

Sensation is usually not passive. Brains acquire information about their environment actively by selecting sensory targets and probing their features. Target selection and feature probing is controlled by the motor components of sensory systems that either move the sensory organ [e.g., eye, hand, tongue or whisker (in rodents)], move the sensed material across it (e.g., sniffing) or emit sensible energy that interacts with the object (e.g., echolocation in bats or electrolocation in electric fish). Thus, during active sensing, motor and sensory components of the same sense modality are intimately related to each other. How these intimate relations are implemented across the multiple neuronal loops connecting motor and sensory stations, how motor-sensory coordination optimizes sensation, and how out of all these perception emerges are exciting open questions.

 

Our department offers a rich and diverse range of research directions on active sensing and motor-sensory loops in a variety of animal systems: bat echolocation, human smelling, vision and touch, and rodent whisker-touch. Based on accumulated experience in these systems, advanced research approaches are employed across several research groups in our department, which enable accurate tracking of the interactions between sensory organs and their environment, detailed recordings and manipulations of the relevant neuronal components at various levels, and quantification of animal behavior.  Combinations of these methods with conceptual theories and mechanistic models allow addressing the challenging, and fascinating questions related to active sensing, aiming at understanding how perception emerges from interactions between brains and environments.

Sensory Processing and Perception

Sensory perception may appear easy and straight forward, as it seems to be a simple detection process that merely involves “capturing” the environmental signals and feeding them into the brain. However, a growing body of recent research reveals that neuronal mechanisms underlying sensory perception are among the most complex of all brain operations- engaging the lion share of the human brain. At the scientific level- understanding the process by which physical energy impinging on the organism is transformed into an inner sensory experience is one of the most difficult challenges in modern neuroscience.  It necessitates studying all levels of resolution- from the molecular mechanisms to the organism’s behavior.  Furthermore, integrating this multi level information into a coherent theory necessitates close interaction between experimentalists and theorists.

 

Following this overall strategy our department offers a rich and diverse range of research directions on sensory processing and perception.  We study this issue at different levels of system integration- starting from single receptors and neurons, through brain circuits and networks, all the way to brain imaging and behavior of the entire organism.  We conduct research on different senses (touch, olfaction, taste, audition and vision), various behaviors (e.g., object perception and echo location), and across different animal species ranging from rodents through bats all the way to humans. Finally, we conceptualize these research results in detailed, large scale models.  These diverse lines, which nevertheless converge on a single fundamental question (that is, how brains perceive), provide synergistic knowledge essential for tackling this difficult yet exciting challenge: understanding the elusive link between sensation and the perceptual experience.

Social Interaction and Group Behavior

Physical and emotional interactions between individuals, and within a group, can induce positive emotional states, and lead to physiological adaptations and behavioral changes necessary for relaxation, resilience, attachment, growth, achievements, and healing. Social support and positive social experiences have well documented health benefits, such as reduction of the risk for a wide range of diseases, including cardiovascular dysfunction, high blood pressure, anxiety and mood disorders. However, the molecular and cellular substrates that mediate the effects of social stimuli and which underlie the benefits of positive social experiences are poorly understood, as are the behavior and gene interaction implications of positive social experiences. Therefore, understanding the neurobiology of social interactions by focusing on the brain circuits and genes, which are associated with, or altered by, the social stimuli, will provide important insights into the brain mechanisms by which social interaction affects psychological and physiological processes.

 

A major challenge in sociobiology, behavioral science, and neuroscience, is the identification and quantification of social interactions under normal and pathological conditions. To that end, several research groups in our department are currently engaged in research aimed to quantify and manipulate gene activation patterns, physiological traits, and behavioral outcomes of group interaction of mice in a semi-natural environment over extended time scales.