Unit 1 "The Brain" ID Terms

Definitions from AMSCO Book

Neuroanatomy

is the study of the structures of the nervous systems, which include the brain and the nerves that run throughout the body.

Central nervous system

is literally “the brains of the operation” — it coordinates the actions and interactions of the other systems in the body; brain and spinal cord.

Brain

is the dominant part of the central nervous study.

Spinal cord

is the avenue through which the brain communicates with the rest of the body.

Meninges

membranes that cover & protect the brain & spinal cord.

Dura mater

meaning “tough mother” in Latin, which is the outermost layer.

Cerebrospinal fluid

the brain sits in the skull and is surrounded by this, which cushions and protects the brain.

Peripheral Nervous System

includes the nerves outside the brain and spinal cord that connect the central nervous system to the rest of the body. It has two major divisions: the motor pathway and sensory pathway.

Somatic Nervous System

includes the nerves that transmit signals from your brain to the skeletal muscles to allow voluntary movement.

Autonomic Nervous System

controls functions that we do not have to think about.

Sympathetic Nervous System

The emergency response system. The person’s heart rate tends to increase, attention becomes more focused, digestion slows, muscle tension increases, and adrenaline flows into bloodstream.

Parasympathetic Nervous System

the default condition of the (ANS). It functions to calm the person, reduces energy expenditure, decreases blood sugar, increases blood flow to the digestive organs, and decreases heart rate, among other things. It allows us to rest and digest.

Reflex arc

occurs when a signal is sent from a sensory organ to the spinal cord, which processes the information instead of passing it on to the brain.

Paul Broca

studied patients who had lost the ability to speak.

Carl Wernicke

studied patients who had lost the ability to understand language.

Broca’s Area

parts of the brain which moves the muscles to create speech.

Wernicke’s Area

parts of the brain which processes both spoken and written language.

Ablation

the process of removing or destroying some brain tissue, leaving lesions, or tissue damaged from the surgery, behind.

Lesions

any abnormal damage or change in the tissue of an organism.

Prefrontal lobotomy

an operation that uses ablation to control behavior. Developed in the 1930s, this process involves with disconnecting the prefrontal cortex, a part of the brain directly behind the forehead, from the rest of the brain.

Hemispherectomy

a type of brain surgery used to treat behavioral disorders or diseases; it involves with the removal of one of the halves (cerebral hemisphere) of the brain.

Deep brain stimulation

a newer, less invasive method of altering the brain to eliminate behavioral symptoms; a surgeon first creates an opening in the skull and then carefully inserts an electrode through the opening and deep into the brain, all the way down into the brain stem.

Transcranial Magnetic Stimulation (TMS)

a noninvasive technique that alters brain activity. It involves the use of an electromagnetic and that alters the magnetic fields that affect how the brain processes emotions and moods. This noninvasive technique is sometimes used to treat depression.

Electroencephalogram

used to record electrical activity in the brain.

Magnetic Resonance Imaging (MRI)

an imaging technique that uses a magnetic field and pulses of radio waves to generate detailed images of parts of the body made up of soft tissue, so they are especially useful when it’s necessary to see the structure of the brain or other internal organs.

Functional Magnetic Resonance Imaging (fMRI)

a variation on the MRI process; it involves using magnetic resonance imaging to visualize blood flow and oxygen metabolism to infer brain activity; this will show where the oxygen is taken up from the blood during any particular activity, and scientists can then identify the parts of the brain that are involved in that activity; this has allowed scientists to create 3-D activation maps of the brain in real time.

Computerized Axial Tomography (CT or CAT scan)

involves taking two-dimensional x-ray photographs from different angles and using them to create a three-dimensional representation of an organ or other body part; these scans can detect brain damage and measure blood flow in the brain, but the most common and probably most effective use is to identify muscle or bone disorder, a tumor, or a blood dot; this type of scanning id often used in emergency rooms because the technique helps doctors to identify critical problems in the lungs and abdomen very quickly; this type of scanning can examine bones, soft tissue, and blood vessels all at the same time.

Positron Emission Tomography (PET Scan)

images allow researchers to visualize slices of the brain to examine deep brain structures that had previously been reachable only via invasive procedures such as surgery; during this scan scientists inject a radioactive “tracer” molecule into a person’s bloodstream.

Endocrine system

a system that sends its signals by passing hormones through the bloodstream (circulatory system); plays a critical role in raising and lowering a person’s blood sugar (glucose) levels, making a person feel hungry or full, regulating metabolism and sleep, and determining sex drive.

Hormones

sent through the bloodstream to send its signals in the endocrine system; are secreted (produced and passed on) from a number of different parts of the body and select parts of the brain.

Hypothalamus

a structure that signals the pituitary gland and helps regulate hunger, thirst, flight or fight, and sex; one of the most important parts of the brain, working in conjunction with many other brain parts to regulate feeling sexuality attracted to others (oxytocin) and bonding emotionally with others (oxytocin and vasopressin).

Pituitary gland

a gland that is sometimes called the Master Gland; regulates stress, growth, and reproduction, including some parts of pregnancy and childbirth.

Gigantism

excessive growth and height

Acromegaly

a potentially disfiguring and deadly condition that includes visible swelling of the soft tissue, resulting in large hands, feet, nose, lips, and ears.

Dwarfism

a condition in which a person grows very slowly and as an adult is typically proportional but notable shorter than average.

Thyroid gland

a type of gland that secretes thyroxin, which affects body metabolism.

Pineal gland

a type of gland that releases melatonin, which is a hormone that helps to regulate sleep and body rhythms.

Adrenal glands

a type of gland that sit atop the kidneys and release adrenaline, which helps to regulate arousal, and corticosteroids.

Gonads

secrete hormones that regulate development of sex characteristics and possibly sex-typical behaviors.; these hormones include androgens, estrogen, and progesterone.

Corpus callosum

latin for “tough body”, a bundle of nerve fibers that connects the two hemispheres.

Cerebral cortex

a type of cortex that is the outer layer of the brain

Sulci

the tissue of the cerebral cortex is folded in on itself, forming this; grooves on the brain.

Gyri

the tissue of the cerebral cortex is folded in on itself, forming this; forming folds or bumps on the brain.

Lobes

the cerebral cortex is divided by these

Association areas

all four lobes (frontal, parietal, occipital, temporal) contains this type of area; these type of areas take up more space by far in the cerebral cortex than the areas devoted to processing sensory and motor signals; these type of areas process higher-order functions — thinking, remembering, planning, forming judgements, and speaking.

Motor cortex

a type of cortex that is located in the frontal lobe; it plays a large role in voluntary movements, receiving information from and working with other parts of the brain.

Parietal lobe

a type of lobe that is behind each frontal lobe — roughly on the top of the head; this area of the brain is important for processing certain sensory signals from the body: touch, pressure, temperature, and pain.

Somatosensory cortex

a type of cortex that is a specific area of the parietal lobe

Occipital lobe

a type of lobe that is at the back of each hemisphere; this lobe processes visual signals and coordinates various aspects of vision.

Temporal lobes

a type of lobe that is near the ears; they are important for processing auditory information and auditory memory.

Brain stem

the oldest part of the brain

Medulla oblongata

is responsible for maintaining and regulating heart rate, breathing (respiration), digestion, swallowing and even sneezing; damage to this often lead to death.

Midbrain

located just above the pons, is involved in vision, movement, hearing, and muscle coordination, although it is not the central processing unit; it is rather an assistant.

Cerebellum

“little brain, is a collection of brain cells with some major responsibilities, including fine motor control, coordination, posture, and balance; if this is damaged, a person might experience problems with balance and coordination, judging distances, and knowing when and where to stop moving forward, walking in a straight line, and many also develop tumors.

Reticular formation

a network of nerves that carry messages between parts of the brain stem; helps regulate the intensity of pain and controls some parts of the body; also helps people focus on sensory input while filtering out unnecessary stimuli.

Limbic system

a type of a system that is located at the top of the brain stem; sometimes called the mammalian brain because other mammals have a similar structure in their brains; includes the thalamus, the hippocampus, the amygdala, the fornix, and the hypothalamus; helps us process emotions.

Thalamus

part of the limbic system that serves as a relay station between the brain stem and the cortex; sensory signals are sent from the sense organs to this.

Hippocampus

part of the limbic system that is latin for “seahorse”; is a rounded part of the limbic system near the center of the brain; plays and important role in turning information into long-term memories and in recalling facts and events.

Amygdala

part of the limbic system that is primarily involved in processing emotion an survival responses; Latin word for “almond”; becomes active during potentially threatening situations.

Lateral hypothalamus (LH)

a type of hypothalamus that plays a key role in eating; regulates hunger; signals from the stomach are carried to the brain by the vagus nerve, where they are received by this; if damaged the person will not experience hunger.

Ventromedial hypothalamus (VMH)

a type of hypothalamus that plays a key role in eating; regulates the feeling of fullness (satiety); individuals that have this damaged will never feel full.

Nucleus accumbens

located near the hypothalamus but is part of the frontal lobe (and is part of the basal ganglia, which is connected to learning habits and motor skills); its primary role of cognitive processing of pleasure, aversion, motivation, learning, and reward; where dopamine is released when we experience pleasure; plays a role in addiction.

Brain lateralization/ hemispheric specialization

the division of labor

Split brain

when the two hemispheres can’t communicate, each side of the brain seems to act independently, seemingly without awareness or knowledge if the other.

Neuroplasticity

the incredible ability to recover from having only “half brain”; the reorganization of neural pathways as a result of experience; stronger when we are young and reduces as we age.

Pons

a mass of nerve fibers that serve as relay stations, sending information from the brain stem to the cerebellum and cortex.