What is the primary function of the brain?
To produce behaviour — coordinated movements that are internally generated, often in response to external stimuli.
What are the three main functions of the nervous system?
Sensory Input (signals from receptors to CNS)
Integration (analysis & response formulation)
Motor Output (commands sent to effector cells).
What does Principle 1 state?
Neuronal circuits are the functional units of the nervous system.
What insight does agenesis of the cerebellum provide about brain function?
It shows the cerebellum’s role in motor coordination, balance, gait, speech, and cognition. Despite deficits, brain plasticity allows partial compensation.
What does Principle 2 state?
Sensory and motor divisions pervade the nervous system (e.g., Bell & Magendie: dorsal = sensory, ventral = motor).
What does Principle 3 state?
The CNS functions on multiple levels, organized hierarchically and in parallel.
What does Principle 4 state?
Many brain circuits are crossed (exceptions: olfaction, some ANS/SNS/ENS).
What does Principle 5 state?
Brain functions are localized and distributed.
What does Principle 6 state?
The brain is symmetrical and asymmetrical (e.g., left = language, right = spatial).
What does Principle 7 state?
The nervous system balances excitation and inhibition.
What does Principle 8 state?
The brain divides sensory input into “what” (ventral recognition) and “how” (dorsal action).
What does Principle 9 state?
The brain constructs its own subjective reality from sensory input
What does Principle 10 state?
Neuroplasticity is the hallmark of nervous system function.
What protects the CNS?
The meninges (dura, arachnoid, pia) and cerebrospinal fluid (CSF).
What is meningitis?
Inflammation of meninges caused by infection; symptoms include severe headache, stiff neck, convulsions.
What is encephalitis?
Infection of brain tissue; can cause severe neurological effects.
What is gray matter?
Neuron cell bodies, dendrites, capillaries.
What are nuclei (CNS)?
Clusters of neurons inside the CNS.
What is white matter?
Myelinated axons connecting brain regions.
What are ganglia (PNS)?
Clusters of neuron cell bodies outside the CNS.
What are tracts?
Collections of axons in the CNS.
What are nerves?
Collections of axons in the PNS.
What are the main parts of the forebrain?
Cerebral cortex, basal ganglia, hippocampus, amygdala, olfactory bulbs.
What is the neocortex’s function?
Perception, planning, emotions, memory, constructing reality.
