Chapter 2 Flashcards
What is a neuron, and what are its three parts?
A neuron is a specialized cell that conducts messages through the nervous system. Its three main parts are the cell body, dendrites, and axon.
What is a synapse?
A synapse is the junction where the axon terminal of the sending neuron communicates with the receiving neuron across the synaptic cleft.
What is the action potential?
The action potential is the firing of a neuron that results when the charge within the neuron becomes more positive than the charge outside the cell’s membrane.
What are neurotransmitters, and what role do they play in the transmission of signals from one neuron to another?
Neurotransmitters are chemicals released into the synaptic cleft from the axon terminal of the sending neuron. They cross the synapse and bind to receptor sites on the receiving neuron, influencing the cell to fire or not to fire. Neurotransmitters regulate the actions of our glands and muscles, affect learning and memory, promote sleep, stimulate mental and physical alertness, and influence our moods and emotions, from depression to euphoria.
What are some of the ways in which neurotransmitters affect our behaviour, and what are some of the major transmitters?
Neurotransmitters affect how we learn, move, feel, and react to our world. Although many chemicals function as neurotransmitters, some of the major ones are Acetylcholine, monoamines (including dopamine, norepinephrine, and seratonin), amino acids (including glutamate and and GABA), and endorphins.
Why is an intact spinal cord important to normal functioning?
The spinal cord provides the link between the body and the brain. The spinal cord also has reflexes which help us to avoid injury.
What are the crucial functions handled by the brainstem?
The brainstem contains (1) the medulla, which controls heartbeat, breathing, blood pressure, coughing, and swallowing; (2) the reticular formation, which plays a crucial role in arousal and attention and screens messages coming into the brain; and (3) the pons, which plays a role in body movement and exerts an influence on sleep and dreaming.
What are the primary functions of the cerebellum?
The main functions of the cerebellum are to execute smooth, skilled movements and to regulate muscle tone and posture.
What is the primary role of the thalamus?
The thalamus acts as a relay station for information flowing into or out of the higher brain centres.What are some of the processes regulated by the hypothalamus?The hypothalamus controls the pituitary gland and regulates hunger, thirst, sexual behaviour, body temperature, our biological clock, and a variety of emotional behaviours.
What is the role of the limbic system?
The limbic system is a group of structures in the brain, including the amygdala and the hippocampus, that are collectively involved in emotion, memory, and motivation.
What are the cerebral hemispheres, the cerebral cortex, and the corpus callosum?
The cerebral hemispheres are the two halves of the cerebrum, connected by the corpus callosum and covered by the cerebral cortex, which is responsible for higher mental processes such as language, memory, and thinking.
What are some of the main areas within the frontal lobes, and what are their functions?
The frontal lobes contain (1) the motor cortex, which controls voluntary motor activity; (2) Broca’s area, which functions in speech production; and (3) the frontal association areas, which are involved in thinking, motivation, planning for the future, impulse control, and emotional responses.
What are the primary functions of the parietal lobes in general and the somatosensory cortex in particular?
The parietal lobes are involved in the reception and processing of touch stimuli. They contain the somatosensory cortex, where touch, pressure, temperature, and pain register.
What are the primary functions of the occipital lobes in general and the primary visual cortex in particular?
The occipital lobes are involved in the reception and interpretation of visual information. They contain the primary visual cortex, where vision registers in the cerebral cortex.
What are the major areas within the temporal lobes, and what are their functions?
The temporal lobes contain (1) the primary auditory cortex, where hearing registers in the cortex; (2) Wernicke’s area, which is involved in comprehending the spoken word and in formulating coherent speech and written language; and (3) association areas, where memories are stored and auditory stimuli are interpreted.
