Brain Basics

Question 1

What is the largest part of the human brain?

Answer 1

The cerebrum.

Question 2

How is the cerebrum divided, and what connects its hemispheres?

Answer 2

The cerebrum is divided into two large, separate hemispheres, connected by bundles of nerve fibers, with the largest bundle forming the corpus callosum.

Question 3

What is the name of the bridge between the cerebral hemispheres?

Answer 3

The corpus callosum.

Question 4

What is the deeply folded layer of nerve tissue on the surface of the cerebrum called?

Answer 4

The cerebral cortex.

Question 5

Where are the frontal lobes located, and what functions do they coordinate?

Answer 5

The frontal lobes are located at the front of the brain, immediately above the eyes. They coordinate higher cognitive skills like planning and problem-solving, and many aspects of personality.

Question 6

What is the function of the parietal lobes, and where are they located?

Answer 6

The parietal lobes are located at the top of the brain, immediately behind the frontal lobes. They integrate sensory signals from the skin, process taste, and handle some types of visual information.

Question 7

Which lobes of the brain process visual information and are responsible for recognizing colors and shapes?

Answer 7

The occipital lobes process visual information and are responsible for recognizing colors and shapes, integrating them into complex visual understanding.

Question 8

Where are the temporal lobes located, and what functions do they carry out?

Answer 8

The temporal lobes lie on the sides of the brain, at and below the level of the eyes. They carry out some visual processing and interpret auditory information.

Question 9

What structures in the temporal lobes encode new memories and integrate memory and emotion?

Answer 9

The hippocampus encodes new memories, and the amygdala integrates memory and emotion.

Question 10

What is the limbic system, and which structures are part of it?

Answer 10

The limbic system is a group of structures deep within the brain that help regulate emotion and motivation. Structures include the hippocampus, amygdala, thalamus, and hypothalamus.

Question 11

What does the midbrain include, and what functions does it coordinate?

Answer 11

The midbrain includes distinct groups of neurons that coordinate eye movements, trigger reflexes to sounds, and help manage fine motor control.

Question 12

What is the function of the pons?

Answer 12

The pons influences breathing and posture.

Question 13

What is the structure that carries nerve pathways connecting the brain to the spinal cord and controls basic functions like swallowing, heart rate, and breathing?

Answer 13

The medulla.

Question 14

What is the second largest part of the brain and it’s function?

Answer 14

The cerebellum, it coordinates voluntary movements, helps in learning new motor skills, and plays roles in spatial and temporal perception.

Question 15

Which part of the brain plays roles in glucose regulation and sleep and includes several regions that help control movement?

Answer 15

The hindbrain.

Question 16

Which kind of damage can cause this type of situation: a jerky, arrhythmic gait or might be unable to accurately touch his finger to his nose

Answer 16

Cerebellum damage.

Question 17

What is the brainstem composed ?

Answer 17

The midbrain, pons, and medulla

Question 18

How did the earliest vertebrates’ brains, like the lancelet’s, differ from more complex brains?

Answer 18

It were little more than a wide spot in the hollow nerve cord, processing specific information about light and chemicals.

Question 19

In early development, how is the human brain divided, and what regions are retained from our ancestors?

Answer 19

The human brain is divided into forebrain, midbrain, and hindbrain, retaining regions from our ancestors’ brains.

Question 20

What specialized regions exist in the lancelet’s brain, and what kinds of information do they process?

Answer 20

The lancelet’s brain contains specialized regions where neurons process specific information, such as the presence of light or chemicals in the water.

Question 21

What are the three distinct bulges that developed in the end of the nerve cord in early vertebrates, and what did they become?

Answer 21

The three distinct bulges at the end of the nerve cord in early vertebrates became the forebrain, midbrain, and hindbrain.

Question 22

How did the forebrain, midbrain, and hindbrain evolve to support specific functions in early vertebrates?

Answer 22

The forebrain evolved to detect chemicals and process complex visual signals, the midbrain coordinated escape movements, and the hindbrain controlled movement.

Question 23

How did the cerebellum’s function change as vertebrates evolved, and why was this change significant?

Answer 23

The cerebellum appeared as part of the hindbrain and expanded to control escape movements and orient the body in space.

Question 24

What is the significance of neural networks in the brain?

Answer 24

There’s routing signals through the brain, analyzing and organizing different types of information.

Question 25

Explain the process your brain undergoes when watching a movie, from visual input to recognition.

Answer 25

The brain processes visual input from a movie through photoreceptors, optic nerve, thalamus, and primary visual cortex, creating a three-dimensional representation of the outside world.

Question 26

How does the thalamocortical loop contribute to the integration of sensory information in the brain?

Answer 26

It connects the thalamus with parts of the cortex, allowing signals to loop through and produce brain waves.

Question 27

What are brain waves, and what do alpha, beta, theta, and delta waves indicate about brain activity?

Answer 27

Brain waves include alpha (relaxed), beta (processing sensory input or concentrating), theta (slow during sleep), and delta (very slow during deep sleep).

Question 28

What are the distinct types of neural networks found in the brain and spinal cord, and what functions do they serve?

Answer 28

spinal tracts, thalamic pathways, and loops connecting the hippocampus and basal ganglia.

Question 29

How are signals processed in neural circuits within the cerebral cortex, and what role do these circuits play?

Answer 29

Signals in neural circuits within the cerebral cortex are transformed and processed in columns, each dedicated to a specific task, with nearby circuits influencing each other dynamically.

Question 30

What percentage of neurons in the brain is excitatory, and what is their primary function?

Answer 30

About 80 percent of neurons in the brain are excitatory, and their primary function is to send signals.

Question 31

What is the most common type of excitatory neuron in many parts of the cerebral cortex?

Answer 31

Pyramidal cell

Question 32

Describe the structure of a pyramidal cell and its dendrites.

Answer 32

A pyramidal cell has a cone-shaped cell body and two sets of branched dendrites—one set at the apex and another at the base.

Question 33

What is the function of inhibitory neurons, and how do they regulate the activity of neighboring neurons?

Answer 33

Inhibitory neurons send signals that suppress the activity of neighboring neurons and regulate the activity of a circuit.

Question 34

How are excitatory and inhibitory neurons typically distributed in neural circuits?

Answer 34

Excitatory neurons tend to be widespread in circuits and send signals forward, while inhibitory neurons often loop their responses back to earlier segments of a circuit.

Question 35

What is the role of excitatory neurons in sending signals through a neural circuit?

Answer 35

Excitatory neurons send signals forward through a circuit and eventually send outputs to other parts of the brain.

Question 36

Explain the concept of feedback inhibition and how inhibitory neurons regulate circuit activity.

Answer 36

Feedback inhibition occurs when inhibitory signals are sent to adjacent columns, reducing their activity.

Question 37

What is the significance of the interplay between excitatory and inhibitory signals in a neural circuit?

Answer 37

It is important in learning, tuning, and smoothing signals sent to the body and other parts of the brain.

Question 38

How might imbalances in excitatory and inhibitory neuron activity contribute to?

Answer 38

To seizure disorders like epilepsy.

Question 39

What is the functional unit of neural circuits and networks, and what is the role of a neuron?

Answer 39

The functional unit of neural circuits and networks is the neuron, a specialized cell that can transmit electrical signals to other nerve cells, muscles, or glands.

Question 40

What are the main types of glial cells in the central nervous system?

Answer 40

The main types of glial cells in the central nervous system are astrocytes, microglia, ependymal cells, and oligodendrocytes.

Question 41

What support cells are the neurons associated with?

Answer 41

Cells called Glia

Question 42

What roles do astrocytes, microglia, ependymal cells, and oligodendrocytes play in the central nervous system?

Answer 42

Astrocytes regulate ion concentrations around neurons, provide nutrients, and help regulate the formation of new connections. Microglia function as immune cells and phagocytes. Ependymal cells make cerebrospinal fluid, and oligodendrocytes wrap axons in myelin.

Question 43

How do ions cross a neuron's cell membrane, and what role do ion channels play in influencing the neuron's voltage difference?

Answer 43

Ions cross a neuron's cell membrane through ion channels, which act like gates. Ion channels allow some ions to enter or leave the cell, changing the voltage difference across the membrane.

Question 44

What is the resting membrane potential of a neuron, and how is it affected by signals from other neurons in its circuit?

Answer 44

The resting membrane potential of a neuron is around -70 millivolts (mV), more negative inside the cell than on its outer surface. It is affected by signals from other neurons in its circuit.

Question 45

What happens if the sum of signals at the dendrites reaches the membrane's threshold voltage?

Answer 45

If the sum of signals at the dendrites reaches the membrane's threshold voltage, voltage-sensitive ion channels open, triggering an action potential.

Question 46

What is the synaptic cleft, and how do neurotransmitters facilitate communication between neurons?

Answer 46

The synaptic cleft is the space between the end of an axon and the dendrite of an adjacent neuron. Neurotransmitters facilitate communication by crossing the synaptic cleft.