The Biological Bases of Behaviour - Chapter 3 Review

Flashcards covering key concepts related to the biological bases of behavior, including neuron structure and function, neural impulses, neurotransmitters, the nervous system divisions, and brain anatomy and imaging techniques.

What are the four main parts of a neuron?

Cell body (soma), Dendrites, Axon, and Axon Terminals.

What is the function of the dendrites in a neuron?

They are "branches" from the cell body that receive signals.

Which part of the neuron conducts electrical impulses away from the soma?

The Axon.

What are glial cells and what is their primary role?

They are support cells for neurons, holding them in place, making and moving nutrients, forming the Myelin Sheath, removing toxins, and forming the blood-brain barrier.

What are the two basic functions of neurons?

To generate electricity (create nerve impulses) and to release chemicals (communicate with other cells).

What is the resting potential of a neuron?

The electrical potential when the cell is at rest, typically -70mV, due to a concentration of sodium ions outside and negative protein ions inside.

What event causes an action potential, or neural impulse, in a neuron?

When the cell is stimulated, electrical charges (ions) flow across the cell membrane, reversing the charge of the resting potential.

What is the absolute refractory period?

A period during which a neuron cannot fire again, limiting the frequency of nerve impulses and ensuring they travel in a single direction.

Explain the All-or-None Law concerning action potentials.

Action potentials occur at a uniform and maximal intensity, or they do not occur at all. Stronger signals do not cause stronger action potentials, but rather create more action potentials (increase the rate of cell firing).

What is the Myelin Sheath and what is its function?

A fatty, whitish insulation layer derived from glial cells that insulates neurons and allows for faster signal conduction.

What are Nodes of Ranvier?

Places where the myelin is either extremely thin or absent, allowing conduction to "skip ahead" and facilitating faster signals.

What is a synapse?

A functional connection between neurons and their target cells, where communication occurs across a gap called a synaptic cleft without physical contact.

What are neurotransmitters?

Chemical substances that carry messages across the synapse to either excite or inhibit the firing of other neurons.

What are the five stages of chemical communication by neurotransmitters?

Synthesis, Storage, Release, Binding, and Deactivation.

What is the difference between an inhibitory and an excitatory neurotransmitter?

Inhibitory neurotransmitters increase the resting potential (hyperpolarization), decreasing the likelihood of an action potential. Excitatory neurotransmitters decrease the resting potential (depolarization), increasing the likelihood of an action potential.

Which excitatory neurotransmitter is expressed throughout the brain and is crucial for learning and memory?

Glutamate (glutamic acid).

Which inhibitory neurotransmitter is expressed throughout the brain and is associated with anxiety and motor control?

GABA (gamma-aminobutyric acid).

Which neurotransmitter is involved in muscle movement and memory, and whose deficiency is linked to Alzheimer's disease?

Acetylcholine (ACh).

Which neurotransmitter affects mood, eating, sleep, and arousal, and is implicated in depression and sleeping/eating disorders?

Serotonin.

Which neurotransmitter is involved in voluntary movement, learning, motivation, and pleasure, and is linked to Parkinson's disease and Schizophrenia?

Dopamine.

What are the three types of neurons?

Sensory neurons, Motor neurons, and Interneurons.

What is the function of sensory neurons?

They carry input messages from the sense organs to the spinal cord and brain.

Which type of neuron is the most common and performs connective or associative functions within the nervous system?

Interneurons.

What are the two main divisions of the Nervous System?

The Central Nervous System (CNS) and the Peripheral Nervous System (PNS).

What are the two main divisions of the Peripheral Nervous System (PNS)?

The Somatic Nervous System and the Autonomic Nervous System.

What functions are regulated by the Autonomic Nervous System?

Involuntary functions such as respiration, circulation, digestion, as well as aspects of motivation, emotional behavior, and stress responses.

Which part of the autonomic nervous system is associated with the "fight-or-flight" response?

The Sympathetic nervous system.

Which part of the autonomic nervous system slows down body processes and returns the body to a state of rest?

The Parasympathetic nervous system.

What are spinal reflexes?

Simple stimulus-response sequences that are triggered at the level of the spinal cord without brain involvement.

What are the three main anatomical divisions of the brain?

The Forebrain, Midbrain, and Hindbrain.

What are the major structures found in the Forebrain?

The Cerebral cortex, Basal ganglia, Limbic system (Hippocampus, Amygdala, Nucleus accumbens), Thalamus, and Hypothalamus.

Which forebrain structure is the outer layer of the cerebral hemispheres involved in thinking and mental processes?

The Cerebral Cortex.

What is the primary function of the Thalamus?

It relays incoming sensory information to the appropriate region in the cortex.

Which brain structure regulates basic biological drives such as hunger and thirst?

The Hypothalamus.

Which part of the limbic system is primarily involved in memory?

The Hippocampus.

Which part of the limbic system is associated with emotional responses?

The Amygdala.

What midbrain structure is involved in the regulation of consciousness, sleep, wakefulness, and attention?

The Reticular Formation.

Which hindbrain structure controls vital functions like heart activity, breathing, swallowing, and digestion?

The Medulla.

Which hindbrain structure is a relay station for signals, regulates sleep and dreaming, and controls muscles in the face and neck?

The Pons.

Which hindbrain structure controls bodily coordination, balance, muscle tone, and is involved in procedural memory?

The Cerebellum.

What are the four lobes of the cerebral cortex?

Frontal Lobe, Parietal Lobe, Temporal Lobe, and Occipital Lobe.

Which cortical area controls voluntary body movements?

The Motor Cortex (located in the Frontal Lobe).

Which cortical area is responsible for receiving sensations of heat, touch, cold, balance, and body position?

The Somatic Sensory Cortex (located in the Parietal Lobe).

Where is the Primary Visual Cortex located?

In the Occipital Lobe.

Which area of the brain is involved in language comprehension?

Wernicke's area.

Which area of the brain is involved in normal speech production?

Broca's area.

What is hemispheric lateralization?

The specialization of function in each of the two cerebral hemispheres, where the right hemisphere generally handles feelings, intuition, and spatial awareness, while the left handles analytical thinking, logic, and language.

What is the function of the corpus callosum?

It is a bridge of nerve fibers that connects the two cerebral hemispheres, allowing the transfer of information between them.

What condition results from severing the corpus callosum?

A "split-brain" condition, where the hemispheres can no longer directly communicate.

Which brain imaging technique measures electrical activity via electrodes on or in the skull, offering very good time resolution?

Electroencephalography (EEG).

Which brain imaging technique uses x-rays to build a picture of the gross features of the brain?

Computer Tomography (CT).

Which brain imaging technique uses trace amounts of short-lived radioactive material to map functional processes in the brain?

Positron Emission Tomography (PET).

What is the primary difference between structural MRI and fMRI?

Structural MRI reveals gross features and structure of the brain, while fMRI detects changes in blood oxygenation and flow to measure neural activity.

Which brain imaging technique builds a picture of water movement in the brain using an MRI scanner to observe blood flow along specific neural tracts?

Diffusion Tensor Imaging (DTI).

Which non-invasive technique can temporarily disrupt or activate cortical neural tissue using a magnetic field?

Transcranial Magnetic Stimulation (TMS).