AP 2 2.1: The Brain (part 2) Flashcards
diencephalon
The hypothalamus, thalamus, and epithalamus are collectively in a portion of the brain known as the diencephalon.
hypothalamus
The hypothalamus, forming the floor of the third ventricle, maintains homeostasis, or the constancy of the internal environment.
The hypothalamus also contains centers for regulating basic body functions, such as hunger, sleep, thirst, body temperature, water balance, and blood pressure. The hypothalamus controls the pituitary gland
endocrine system
The hypothalamus controls the pituitary gland which regulates body hormones of the endocrine system, which controls the body’s hormonal production. The hypothalamus serves as a link between the nervous and endocrine systems.
thalamus
The thalamus, in the roof of the third ventricle, is the last portion of the brain for sensory input before the cerebrum . It serves as a central relay station for sensory impulses traveling upward from other parts of the body and the brain to the cerebrum. The thalamus receives all sensory impulses (except those associated with the sense of smell), filters out unimportant sensory information, and directs it to the appropriate regions of the cerebrum for interpretation.
epithalamus
The epithalamus forms the roof of the third ventricle and is mostly composed of the pineal gland
pineal gland
The epithalamus (Figure 2.10) forms the roof of the third ventricle and is mostly composed of the pineal gland . The pineal gland which secretes melatonin, a hormone that controls the wake-sleep cycle.
cerebellum
The cerebellum, located inferiorly and posteriorly to the brain, is convoluted and divided into two hemispheres with deep fissures subdividing it into three lobes. Because of its appearance, it is often called the “mini-brain.” The cerebellum has the gray matter and white matter reversed from the spinal cord. It is composed of a thin outer cortex of gray matter and internal white matter. The cerebellum works to coordinate body movements by relaying information to the cerebral motor cortex. The cerebellum is also involved with maintaining balance, controlling certain eye movements, maintaining normal muscle tone, and maintaining posture. Muscle tone is the degree at which muscles remain partially contracted while at rest. **Muscle tone **is continuously monitored and maintained by the cerebellum to keep bones and joints in place.
anterior lobes and posterior lobes of the cerebellum
The anterior lobes and posterior lobes of the cerebellum (Figure 2.12) receive information from the body trunk and influence the motor activities of the trunk, shoulder, and pectoral girdle muscles.
vermis
cerebellum
The intermediate portion, called the vermis, coordinates limb movements (
cerebellar peduncles and flocculonodular lobes
cerebellum
The cerebellar peduncles and flocculonodular lobes are located on the anterior portion of the cerebellum. The cerebellar peduncles serve to connect the cerebellum to the other parts of the brain
limbic system
he limbic system involves portions of both the unconscious and conscious brain. It lies just beneath the cerebral cortex and contains neural pathways that connect portions of the frontal lobes, temporal lobes, thalamus, and hypothalamus.
The limbic system is our feeling brain because stimulation of different areas of the limbic system causes rage, pain, pleasure, or sorrow. The limbic system affects the emotional aspects of behavior outcomes as well as how people evaluate rewards and consequences. The limbic system is also involved in the processes of learning and memory.
cingulate gyrus
limbic system
The cingulate gyrus, also known as the limbic lobe, is located deep to the cerebrum. The cingulate gyrus serves to connect the different lobes of the cerebrum.
hippocampus
limbic system
The hippocampus is involved in the retrieval and storage of memories.
amygdala
limbic system
The amygdala is a small portion of the limbic system that is involved in emotions such as rage and anger.
fornix
limbic system
The fornix is a bundle of nerve fibers that serves as a connection to the hippocampus
mamillary bodies
limbic system
The mamillary bodies (Figure 2.15) contain fibers that project into the thalamus and assist with the memory of smell.
short-term memory
limbic system
he limbic system is essential to both short-term and long-term memory. An example of short-term memory in humans is the ability to recall a seven-digit telephone number long enough to dial the number.
long-term memory
limbic system
An example of long-term memory is the ability to recall the events of the day. Memories are not stored in one specific area within the brain but instead are stored throughout the cerebral hemispheres. The hippocampus acts as a memory center to help with memory storage and retrieval. The involvement of the limbic system explains why emotionally charged events result in our most vivid memories. The fact that the limbic system communicates with the all the sensory areas accounts for the ability of a sensory stimulus to awaken a complex memory.
basal nuclei
The basal nuclei (also known as basal ganglia) are masses of gray matter that lie deep within each hemisphere of the cerebrum (Figure 2.16). The basal ganglia are also part of the limbic system. The basal ganglia are responsible for working with the cerebellum to regulate planning motor movements and motor learning.
putamen, caudate nucleus, and Globus pallidus (medial and lateral)
basal nuclei
The putamen, caudate nucleus, and Globus pallidus (medial and lateral) are all parts of the basal ganglia. In general, the overall effect of the basal ganglia is to have an inhibitory effect on the cerebral cortex, or to slow and control precise movements. Parkinson’s disease is a disorder of the basal ganglia.
Apraxia
basal nuclei
Apraxia, or difficulty with motor planning, is a symptom of Parkinson’s disease. Apraxia results in rigid movements and difficulty executing a motor plan.
