Neurobiology Quiz: Nervous System Functions

Mechanisms and Levels of Analysis

• A mechanism is a description of a system's behavior built from a description of the actions and interactions of the system's parts.
• Behaviors can be observed in systems like watches, limbs moving, and stock markets.
• Systems not just objects consist of parts: brokers, consumers, and algorithms making trades.

Mechanism of Mind

• Concrete analysis starts with concrete phenomena.
• Example: moths flying to light.
• Brain cells interacting and forming networks are a part of this mechanism.
• The sense of light, the signal of direction, and the movement are crucial steps in the process.

Sensorimotor Behaviors

• Sensorimotor behaviors involve senses, actions, reward, emotions, and memory. These behaviors require understanding how brain cells interact and how information is transformed.
• Behaviors require interactions between brain cells.
• Two ways to analyze behaviors: the interactions between parts (brain cells) and the transformations of information.

Nervous System Overview (Lecture 2)

• The nervous system is made up of the CNS and PNS.
• The CNS includes the brain and spinal cord.
• The PNS includes nerves and the autonomous nervous system.

Cells of the Nervous System

• Neurons transmit signals to each other and organs.
• Glia cells provide support and structural integrity for neurons, like astrocytes and microglia.

Nervous System Directions

• Planes: coronal, sagittal, and horizontal.
• Axes: anterior-posterior, dorsal-ventral, and medial-lateral.

Mechanisms of Behavior (Lecture 1 summary)

• Mechanisms are descriptions of a system's behavior built from actions and interactions of the parts, with information integration.

Nervous System (Summary of Lecture)

• Focuses on the CNS and PNS.
• Breaks down organization into anatomical planes and axes.
• Details organization principles.

Basis of Neurons and Glia

• The basic parts of a neuron are the dendrites, soma, axon hillock, axon, and axon terminals.
• Glial cells include astrocytes (support), oligodendrocytes (insulation in CNS), Schwann cells (insulation in PNS), and microglia (immune response).

Molecules and Electricity in Neurons

• Atoms have electrical charges; electricity is the movement of these charges.
• Water and lipids are important membrane components.
• Ions are important for generating electrical signals in cells.

Membrane Potential

• The membrane potential is the difference in electrical charge across the neuronal membrane.
• Ions contribute differently to the membrane potential based on their concentration gradients and permeability.
• Potassium (K+) and sodium (Na+) ions have significant impacts on membrane potentials.

Ion Channels

• Ion channels open and close to allow specific ions across the membrane, which is critical for neurons functioning.
• Ion channels can be ligand-gated or voltage-gated.

Action Potentials

• Action potentials are rapid changes in the membrane potential that allow the signal to travel down the axon.
• They involve depolarization and repolarization through voltage-gated sodium and potassium channels.

Neuron Communication

• Information is transferred in the form of action potentials and neurotransmitters.
• The neuron releases neurotransmitters to communicate with other neurons.
• Neurotransmitters can have excitatory/inhibitory effects on other neurons depending on the receptor.

Synaptic Integration

• EPSPs (excitatory postsynaptic potentials) move the neuron closer to the threshold.
• IPSPs (inhibitory postsynaptic potentials) move the neuron further away from the threshold.
• At the axon hillock, EPSPs and IPSPs are integrated to determine whether or not an action potential will be triggered.
• Signals from many neurons are integrated at the axon hillock.

Neuron Circuits

• Axons, dendrites, and junctions form circuits of interconnected neurons in the brain.
• These connections allow for complex computations in the brain.
• The signals flow between neurons as action potentials and neurotransmitters.

Different Types of Neuron Signals

• Signals may be excitatory or inhibitory.
• Excitatory signals bring the neuron closer to the action threshold.
• Inhibitory signals move the neuron further from the action potential threshold..

Types of Signals pt 2 & 3 (Lecture)

• Direct: ligand-gated channels
• Indirect: G-protein coupled receptors
• Different neurotransmitters (e.g., glutamate, GABA, acetylcholine, dopamine, norepinephrine, serotonin).

Reward Learning

• Pavlovian conditioning: associating a neutral stimulus with a rewarding stimulus to elicit a response to the neutral stimulus.
• Operant conditioning: associating a behavior with a rewarding or punishing stimulus to increase/decrease the likelihood of the behavior being repeated.

Neural Circuits - Examples (Lectures)

• The stretch reflex: sensory input triggers motor output.
• Oscillating circuits: generate rhythmic behaviors (e.g., breathing).
• Lateral Inhibition: allows greater contrast in sensory information.

Nervous System Organization

• Hierarchical organization
• Sensory → action ("reflex arcs")
• Viscero-sensory → visceral control.

Vision (Lecture)

• Sensory reception (retina)
• Integration (horizontal and amacrine cells)
• Action potentials
• Lateral inhibition
• Information processing (thalamus and cortical areas).

Neural Pathways (Lectures)

• Central nervous system pathways
• Sensory and motor pathways in detail in various parts of brain
• Details involved in information transmission.

Social Communication (Lecture)

• Language (symbolic communication)
• Pheromones
• Sensory modalities

Social Reward

• Motivation for mating and interactions
• The importance of oxytocin and vasopressin
• Social roles (e.g., dominance hierarchies)

Brain Regions Dealing with Emotions and Responses to Threat

• Amygdala
• Medial prefrontal cortex
• Ventral pallidum
• Hypothalamus

Memory (Lecture)

• Hippocampus for making new memories.
• Consolidation, encoding, and retrieval of memories.
• Different types of memory: episodic, semantic, and perceptual.

Sleep (Lecture)

• Circadian rhythms and their role.
• Sleep stages
• Role of sleep in memory consolidation and other functions.

Stress (Lecture)

• The hypothalamic-pituitary-adrenal (HPA) axis.
• Acute and chronic stress responses (hormonal and physiological)
• The importance of homeostasis

Test your knowledge on the primary roles of different cells and neurotransmitters in the nervous system. This quiz covers topics such as astrocytes, axon hillock functions, and the impact of dopamine and acetylcholine on behavior. Perfect for students studying neurobiology or psychology.