Class 10 Olfactory System: Neural Circuits, Plasticity, and Modulation

What is the role of the olfactory bulb in sensory processing?

It allows for global modulation of input based on non-olfactory information, enabling contextual gain control.

How does descending convergence affect odor representations?

It enables odor receptor-based shaping of odorant representations based on non-olfactory information.

What is associative learning in the context of olfactory processing?

It refers to how an odor's meaning is learned based on predictions of future threats or rewards.

What does olfactory prediction involve?

It involves anticipating when a given odor is expected and how that affects processing, attention, and perception.

What changes occur in the olfactory system during different overall states?

Non-olfactory modulation occurs, affecting how the olfactory system processes information.

What neurotransmitters do periglomerular neurons release?

They release GABA, dopamine, or both.

What is the function of periglomerular cells?

They inhibit the release from olfactory receptor neurons (ORN) and inhibit mitral cells through dendro-dendritic inhibition.

Why might a sensory system need to change?

To optimize sensory function for a particular environment or goal.

What are adaptive responses in sensory systems?

Sensory changes that occur in response to stimuli as they are encountered.

What are anticipatory responses in sensory systems?

Sensory changes that occur when a stimulus is expected.

What are ongoing responses in sensory systems?

Sensory changes that last indefinitely.

How do sensory dynamics relate to cognitive components?

They apply existing learned information to better interpret sensory input or couple it to behavior.

What might cognitive dysfunction indicate in sensory processing?

It might manifest in particular forms of dysfunction reflected in sensory processing.

What happens to odor representations in a common environment?

They can change based on learning and conditioning, such as predicting a shock.

What is discriminative fear conditioning?

It yields odor-specific fear and increases in olfactory sensory neuron (OSN) output related to specific odors.

What does plasticity accomplish in olfactory processing?

It allows for changes in odor representations, making them more similar or different based on conditioning.

How does generalizing conditioning affect odor representations?

It causes odor representations to become more similar.

How quickly can changes in olfactory representations manifest?

Changes can happen as early as the olfactory nerve terminal.