KEY DEFINITIONS IN CHAPTER 1 & 2

Neurogenic communication disorder

a disturbance of communciaiton arising from damage to the nervous system.

Cognition

The ability to think, acquire and process knowledge about the world.

Arousal

The level of wakefulness and the ability to resond to stimuli

Orientating

The ability to direct attention toward a stimulus

Attention

The ability to hold focus on a stimulus when aroused enough to know that the stimulus is there and to use orienting skills and direct attention to the stimulus.

Vigilance

The ability to stay alert to the occurrence of a possible stimulus

Sustained attention

The ability to hold attention on a single stimulus.

Selective Attention

The ability to hold attention on a stimulus while ignoring the presence of competing stimuli

Alternating attention

The ability to move or alternate one’s attention back and forth from one stimulus to another.

Divided Attention

The ability to attend to one stimulus while simultaneously attending to another stimulus also known as multitasking

Working Memory

the ability to hold a finite amount of info for immediate processing and manipulating that would within a few seconds if not reinforced

Short-Term memory

The ability to store information in one’s memory in a readily accessible state for a period of only a few seconds or minutes.

• retention of information for seconds and minutes, up to an hour.

Long term memory

The ability to retain information successfully over months or years. 

• unlimited capacity for information

Procedural memory

The memory of sequences of actions (procedures) used to complete tasks;

ex: steps of a recipe or steps to brush your teeth

Declarative memory

the ability to remember facts

Episodic Memory

The recall of specific, recently experienced events (or episodes), EX: Vacation or the first time you rode a bike

Orientation

A person's knowledge of himself or herself, and of his or her place in space and time (ability to know who they are, where they are, and when they are).

Problem-Solving

The ability to find an appropriate solution to a problem.

Inferencing

The ability to make a leap in judgment to a correct interpretation of the overall meaning of the details.

Executive functions

• high-level cognitive systems that employ and manage other lower-level cognitive functions

• housed in prefrontal area of frontal lobe

• use cognitive functions such as attention, memory, planning, problem solving, initiating, and organizational behaviors to meet high-level goals.

3 layers that protect the skull in order from top to bottom

• D : Dura Mater

• A: Arachnoid Mater

• P : Pia Mater

Language

 a set of symbols used to communicate meaning.

Speech

The sounds made by the vocal and articulatory structures of the body to create verbal language.

Neurons

Are the nervous system cells responsible for transmitting and processing information.

Synapse

The point of connection between neurons.

Neuroglia

Cells that provide structural support to neurons and perform other important back-ground functions; are not directly involved in information processing.

Sensory Neurons

Neurons that transmit sensory information from sensory receptor cells of the body to the spinal cord or brain for processing.

Motor Neurons

Neurons that transmit signals of motor movement from the brain and spinal cord out to the body for volitional and autonomic movement.

Interneurons

Neurons that connect to one another within the brain and are involved in processing information rather than transmitting information.

Soma

• cell body of the neuron

• contains the nucleus, organelles, and cytoplasm of the cell.

Dendrites

Branches that extend from the soma to synapse with the axons of other neurons and transmits signals from these axons toward the soma.

Axon

A single long projection extending from the soma, transmits signals from the soma to other neurons.

Terminal Buttons

Small production at the end of an axon that synapse with the dendrites of other neurons.

Obligodendrocytes

are glial cells within the central nervous system (CNS) responsible for the production of the myelin sheath on the axons of neurons that compose white matter.

Myelin

• is a white sheath of protein and fat that insulates the axons

  of neurons (like a rubber sheath insulates the copper wire in electrical

  wiring). 

• An insulating layer of protein and fatty substances that forms around

  the axons of certain neurons and that allows for fast and effective transmission of neural impulses.

Astrocytes

glial cells with multiple functions in the CNS

End feet

The terminal end of astrocytes’ projections that assists in establishing the blood-brain barrier.

• help to wall off the circulatory system from the neurons.

Glial Scar

protective structural support astrocytes that form around a lesion site in the CNS, restricting the spread of inflammatory processes

Astrocytosis

protective process of astrocytes reacting to injury; also function to maintain homeostasis within the CNS by releasing energy to neurons via lactate when needed.

Microglia

the immunological cells within the central nervous system

Schwann cells

produce the myelin sheath around motor and sensory neurons in the peripheral nervous system

Central Nervous System (CNS)

consists of the brain and spinal cord

Peripheral Nervous System (PNS)

• consists of the nerve tracts that connect the rest of the body

  to the central nervous system.

• nerve tracts outside of the central nervous system that connect the central nervous system to the rest ofthe body.

Cerebrum

The rounded gray section of the brain with gyri and sulci.

Cerebral Cortex

The most superficial layer of the cerebrum

Gray matter

• Unmyelinated neurons responsible for processing and regulating information within the nervous system (CNS).

• is found in the cortex and some subcortical structures such as the cerebellum, thalamus, basal ganglia 

White Matter

Myelinated neurons specializing in transmitting information over relatively long distances within the body such as from one area of the brain to another or between the brain and the body.

• consists of the axons of neurons that are covered in myelin

Association Fibers

White matter pathways that connect different structures and areas of the brain within a single hemisphere.

Commissural fibers

White matter pathways that connect analogous areas between the two cerebral hemispheres.

Projection fibers

White matter pathways that project from the brain to the spinal cord and transmit motor signals from the CNS out to the peripheral nervous system and transmit sensory signals from the peripheral nervous system back up through the lower central nervous system to be processed in the brain.

Gyri

Ridges on the visible portion of the cerebral cortex.

Sulci

Inward folds of the cerebral cortex. (Valleys)

Fissures

Deep grooves that create major divisions in the anatomy of the brain.

Lissencephaly

A group of congenital malformations that create a lack of appropriate gyri and sulci of the cortex and a consequent reduction in cortical tissue.

Central Meninges

Three layers of tissues with various functions that encase and envelop the brain and spinal cord.

Dura mater

A dense, fibrous protective layer of tissue that envelops the brain and spinal cord. This is the most superficial layer of the cerebral meninges.

“tough mother”

Arachnoid mater

A layer of the cerebral meninges that exists between the dura mater and the pia mater that plays a large role in supplying blood to the surface of the brain through the many blood vessels it contains.

Pia mater

The innermost and most delicate layer of the cerebral meninges that hugs the surface of the brain and spinal cord closely as it rises and falls along the gyri, sulci, and fissures.

Leptomeninges

(i.e., the arachnoid mater and the pia mater).

Lateral ventricles

two large cerebrospinal-fluid-filled cavities on which the cerebrum rests

Choroid Plexus

tissue within the lateral ventricles where cerebrospinal fluid is produced

Ventricular System

DEF: A number of interconnected cavities within the brain that manufacture and contain cerebro-spinal fluid, which has nutritive and waste removal responsibilities.

cushion the brain from trauma but also manufactures and circulates cerebrospinal fluid to deliver nutrients to the brain and remove waste

Longitudinal fissure

A deep groove running front to back along the brain that divides the brain into the right and left cerebral hemispheres.

Corpus Callosum

A mass of white matter tracts located at the base of the longitudinal fissure that connects the analogous areas between the two hemispheres.

mass of white matter that helps the two hemispheres work in tandem

Prosody

The changes in pitch, stress, timbre, cadence, and tempo a person uses to infuse utterances with emotional content.

Brocas Area

The inferior, posterior region of the frontal lobe of the left hemisphere that is a specialized area of the cerebrum responsible for finding and assembling words for the appropriate expression of thought.

Wernicke’s Area

A specialized portion of the cerebrum located at the superior marginal gyrus of the left hemisphere's temporal lobe that is responsible for interpreting and deriving meaning from the speech of others.

3 structures of basal ganglia

• Caudate nucleus

• Putamen

• Globus pallidus

Central Sulcus

A deep groove that runs down the middle lateral surface of each cerebral hemisphere.

Lateral Sulcus

A deep groove that begins at the lower frontal aspect of each of the two cerebral hemispheres and travels at an upward angle, passes the central sulcus, and then terminates.

Frontal Lobe

Anterior sections of the cerebral hemispheres that are delineated posteriorly by the central sulcus and inferiorly by the lateral sulcus and that houses expressive language within the left and deals heavily in motor movement bilaterally.

Primary motor cortex

A strip of tissue oriented vertically along the last gyrus of each frontal lobe that plays a large role in voluntary motor movement.

Motor Homunculus

A visual illustration of the amount of cortical tissue dedicated to the movement of each body part within the primary motor cortex.

Parietal Lobes

Sections of the cerebrum located posteriorly to the frontal lobes and anteriorly to the occipital lobes that are largely responsible for receiving and processing sensory information concerning the body.

Primary Sensory Cortex

A section of cortex along the first gyrus of the parietal lobe dedicated to receiving and processing sensory information.

Sensory homunculus

A visual illustration of the amount of cortical tissue within the primary sensory cortex dedicated to processing sensory Information from each body part.

Temporal Lobes

Sections of the cerebrum located inferior to the parietal lobes that are largely responsible for memory and processing of auditory stimuli.

Hippocampus

A region of the temporal lobe that is responsible for storing and creating memories; “seahorse”; is located in inferior and medial sections of the temporal lobes

Primary Auditory cortex

A region of cortex located within the temporal lobes responsible for receiving neural impulses related to sound.,

Anterograde Amnesia

an inability to create new memories

Visual Association cortex

 A section of cortex within the occipital-parietal region responsible for processing and interpreting visual information received from the primary visual cortex.

Occipital Lobes

The most posterior sections of the cerebrum that are dedicated to receiving and processing neural impulses related to vision.

Primary Visual Cortex

The most posterior section of the occipital lobes, dedicated to receiving neural impulses of vision from the eyes.

Subcortex

The portion of the brain located beneath the cortex that deals less in reasoning abilities and higher-level cognition and more in autonomic, life-sustaining functions. Brain stem

Brain Stem

A subcortical structure that connects the spinal cord to the rest of the brain and houses many structures involved in autonomic functions.

Medulla

The most inferior section of the brain stem that connects the spinal cord to the pons and that is the site of decussation of a large portion of the motor tracts descending through the brain stem.

Pons

The middle and slightly bulbous portion of the brain stem that provides an attachment between the cerebellum and the rest of the central nervous system.

Mid brain

The most superior section of the brain stem that houses the substantia nigra.

Substantia nigra

A structure located within the midbrain responsible for the production of the neurotransmitter dopamine.

Reticular formation

A series of nuclei stretching among the midbrain, pons, and medulla that regulates arousal, respiration, and blood pressure.

Cerebellum

A subcortical structure hanging off the back of the pons and under the occipital lobes that is known as an error control device for body movement and that ensures that body movements are smoothly coordinated and as error free as possible.

Arbor vitae

The distinctive plantlike shape of the fibers of the cerebellar hemispheres evident upon dissection and some imaging studies.

Vermis

The midline gray matter that connects the two cerebellar hemispheres and receives somato-sensory information about the body through projections coursing through the pons.

Penduncles

Attachments between the cerebellum and the pons.

Thalamus

A subcortical structure that rests on top of the brain stem beneath the cerebrum and functions as a relay station for neural impulses of sensation (excluding olfaction).

Basal Ganglia

A group of subcortical structures located deep within the cerebral hemispheres on either side of the thalamus that works to regulate body movement.

Limibic System

A number of subcortical structures responsible for sense of pleasure, mating and feeding behaviors, fight-or-flight response, emotions, emotional memory, and sense of motivation.

Spinal Cord

A bundle of white matter tracts and gray matter housed within the bony vertebral column that enables afferent (sensory) impulses coming from the body to be transmitted to the brain and efferent (motor) impulses from the brain to be transmitted to the body.

Internal Carotid Arteries

A set of paired arteries that course superior from the thorax within the anterior portion of the neck to the base of the brain to link with the circle of Willis.

Circle of Willis

A series of anastomoses that connect the internal carotid and vertebral/basilar system, ensures equal blood flow to all areas of the brain, and acts as a safety valve if an occlusion occurs within it or below it.