Neuroscience: Brain Structures, Functions, and Motor Control

What are the two main components of the forebrain?

Telencephalon and Diencephalon

What is the primary function of the Thalamus?

It serves as the main relay center for sensory and motor information.

What does the Hypothalamus control?

The autonomic nervous system and the endocrine system, regulating behaviors related to survival.

What are the four externally visible lobes of the human neocortex?

Frontal, Parietal, Temporal, and Occipital lobes.

What is the function of the Prefrontal Cortex?

Formulating plans and strategies, and decision making.

What are the main functions associated with the left hemisphere of the brain?

Controls the right side of the body, number skills, math/scientific skills, written and spoken language, objectivity, analytical thinking, logic, and reasoning.

What functions are associated with the right hemisphere of the brain?

Controls the left side of the body, 3D shapes, music/art awareness, intuition, creativity, imagination, subjectivity, synthesizing, emotion, and face recognition.

What structures are included in the Limbic System?

Limbic cortex, Hippocampus, Amygdala, Fornix, and Mammillary bodies.

What is the primary role of the Basal Ganglia?

Involved in processing information for motor movement.

What is the function of the Midbrain?

Includes structures like the Tectum and Tegmentum, involved in vision and auditory processing.

What are the two divisions of the Autonomic Nervous System?

Sympathetic Division and Parasympathetic Division.

What is synaptic transmission?

The chemical part of electrochemical communication between neurons across a synapse.

What happens at the synapse when an action potential arrives?

Voltage-gated calcium channels open, allowing calcium ions to enter the axon terminal, leading to neurotransmitter release.

What are the two main types of neurotransmitter effects?

Ionotropic effects (fast) and Metabotropic effects (slow).

What is an example of an Ionotropic effect?

Nicotinic receptor for Acetylcholine, which opens cation channels, leading to depolarization.

What is the effect of GABA binding to its receptor?

It opens chloride channels, leading to inhibitory effects on the neuron.

What is the role of the Primary Motor Cortex?

It connects to muscles of different body parts and generates movement.

What is the function of the Motor Association Cortex (Premotor Cortex)?

It controls the primary motor cortex and behaviors related to movement.

What is the significance of the central sulcus?

It is a prominent landmark that separates the parietal lobe from the frontal lobe.

What is the role of the Reticular Formation?

It is involved in regulating arousal and consciousness.

What is the function of the Cerebellum?

It coordinates voluntary movements and maintains posture and balance.

What is the function of the Medulla Oblongata?

It controls vital autonomic functions such as breathing and heart rate.

What do IPSPs do in a neuron?

IPSPs reduce the probability of causing an action potential.

What are metabotropic effects in neurons?

Metabotropic effects cause secondary effects inside the neuron through the activation of G-proteins and second messengers.

What neurotransmitter is associated with muscle contraction at the neuromuscular junction?

Acetylcholine.

What is the role of extrafusal muscle fibers?

Extrafusal muscle fibers are responsible for the force exerted by the contraction of skeletal muscle.

What is the function of intrafusal muscle fibers?

Intrafusal muscle fibers function as stretch receptors in muscle spindles.

What is the difference between muscle spindle and Golgi tendon organ?

Muscle spindles detect muscle length, while Golgi tendon organs detect muscle tension.

What is the primary motor cortex responsible for?

The primary motor cortex directs the contraction of specific muscles and coordinates movements.

What is the function of the basal ganglia in movement?

The basal ganglia are involved in action selection and the initiation of movements.

What happens when there is damage to the cerebellum?

Damage to the cerebellum causes difficulties with rapid movements that require aiming and timing.

What is the role of mirror neurons?

Mirror neurons respond to both performing and observing movements, facilitating imitation and understanding of actions.

What is the significance of the motor homunculus?

The motor homunculus represents the cortical magnification and organization of motor control for different body parts.

What are the two main pathways for motor control from the brain?

The lateral tract for precise movements and the ventromedial tract for bilateral control.

What is the function of the pre-supplementary motor area (preSMA)?

The preSMA is involved in the control of spontaneous movements and the intention to move.

What is Parkinson's disease characterized by?

Parkinson's disease is characterized by muscular rigidity, slowness of movement, resting tremor, and postural instability.

What causes Huntington's disease?

Huntington's disease is caused by degeneration of the caudate nucleus and putamen, leading to uncontrollable jerky movements.

What is the primary treatment for Parkinson's disease?

The primary treatment is L-dopa, a precursor to dopamine that crosses the blood-brain barrier.

What is the role of the reticular formation in movement?

The reticular formation is involved in initiating and regulating movements by connecting with the spinal cord.

What does the term 'dis-inhibition' refer to in the context of the basal ganglia?

Dis-inhibition refers to the process by which inhibition is lifted to allow for certain actions to be executed.

What is the function of the motor endplate?

The motor endplate is the postsynaptic membrane at the neuromuscular junction where acetylcholine binds.

What is the mechanism of muscle contraction involving actin and myosin?

Muscle contraction occurs through the actin-myosin cross-bridge mechanism, initiated by action potentials and calcium influx.

What is the role of proprioceptors in movement control?

Proprioceptors provide the brain with information about current stretch levels and body position.

How does the brain organize movements in space?

The premotor and supplementary motor cortex integrate sensory information to organize the direction of movements.

What is the function of the ventral anterior and ventrolateral nuclei in the thalamus?

These nuclei relay information from the basal ganglia to the motor cortex, facilitating movement control.

What is the significance of the anterior intraparietal sulcus (aIPS)?

The aIPS plays a role in grasping movements and is part of the mirror neuron system.

What is the effect of muscimol on motor tasks?

Muscimol affects learned arbitrary movements but not spatial tasks, indicating its role in motor planning.