Term
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Definition
-surface layer of the cerebrum
-composed of gray matter (neurons)
-contains billions of nerve cells. |
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Term
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Definition
Beneath the cerebral cortex is the cerebral white matter, composed of billions of myelinated nerve fibers that conduct nerve impulses into and out of the cerebral cortex, and also between different areas of the cerebral cortex.
A huge band of these fibers connects the cerebral hemispheres, and is called the corpus callosum. |
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Term
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Definition
-The convolutions or folds in the cerebral cortex.
-Gyri are separated from each other by grooves called sulci.
-Very deep grooves are called fissures. |
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Term
| Longitudinal fissure; Falx Cerebri |
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Definition
A longitudinal fissure separates the right and left cerebral hemispheres.
An extension of the dura mater called the falx cerebri dips down into this fissure. |
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Definition
| contains an important fold or gyrus called the precentral gyrus (landmark for the primary motor area of the cerebral cortex) |
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Definition
seperated from the frontal lobe by the central groove or sulcus
-postcentrral gyrus (landmark for the somatosensory area of the cerebral cortex) |
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Definition
| separated from the frontal lobe by the lateral sulcus or lateral fissure |
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Definition
| forms the posterior portion of each cerebral hemisphere, and is separated from the cerebrellum by a shelf-like extension of the dura mater called the tentorium cerebelli |
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Term
| The insula (latin for “island”) |
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Definition
| Lies deep within the lateral fissure under the parietal, frontal and temporal lobes. Its delineated by a circular sulcus. It has connection with the limbic system |
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Definition
| are involved in our highest intellectual activities and often provide the link between sensation and action. |
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Term
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Definition
-contain primary and higher-order areas
-Primary motor areas execute voluntary movements
-higher-order motor areas are involved in the planning of the movements. |
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Term
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Definition
| is located in the precentral gyrus of the frontal lobe |
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Term
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Definition
-In the frontal lobe
-Coordinates the complex movements of the mouth, toungue, larynx and breathing that make speech possible |
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Term
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Definition
| A patient with a lesion in this area can comprehend speech, but cannot talk properly. |
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Term
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Definition
| It is involved in language reception and comprehension. It processes both verbal and visual commands received by the eyes and ears. |
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Term
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Definition
| a bundle of fibers that connect Wernicke’s area with Broca’s area |
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Term
| A lesion in Wernicke’s area |
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Definition
| does not impair a patient’s ability to speak, but they cannot understand. Such patients often speak fluently, but the words often have little meaning and they cannot convey the ideas they have in their minds. |
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Term
| The primary somatic sensory area |
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Definition
located in the parietal lobe
Damage to this area can lead to loss of fine localization of stimuli, loss of the ability to judge weights, shapes and textures. |
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Term
| Locations of Visual, Auditory, Taste & Smell |
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Definition
primary visual area- occipital lobe
primary auditory area- temporal lobe
Primary areas for taste- parietal
Primary areas for smell- temporal lobea |
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Term
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Definition
-Integrate diverse information
-They often provide the link between sensation and action.
-Association areas are found in regions of the parietal, temporal, occipital and frontal lobes.
-One part of the parietal lobe is known to be important in our awareness of our bodies and where all the parts are located in relation to our surroundings. |
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Term
| Prefrontal association cortex |
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Definition
| has important functions in planning complex voluntary movements, thinking, problem-solving and other highly intellectual functions. |
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Term
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Definition
| a group of gyri and associated structures that roughly encircles the corpus callosum and the diencephalon. |
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Term
| Functions of the limbic system |
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Definition
1) Self-preservation (feeding, fight, flight)
2) Reproduction (mating, care of offspring)
3) Emotions, goal-related behavior, motivation, sensation of reward, pleasure and punishment
4) Memory
5) The limbic system provides a link between the conscious function of the cerebral cortex and the autonomic nervous system and endocrine system via the hypothalamus. |
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Term
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Definition
| Note that nuclei associated with many of these function are found in the hypothalamus. Much of the output of the limbic system goes to the hypothalamus. |
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Term
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Definition
- Procedural or “knowing how” memory
-immediate or working memory
-declarative or “knowing that” memory (divided into short term and long term memory) |
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Term
| Procedural memory or “knowing how” memory |
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Definition
| Concerned with learning of motor skills. Knowing how to type, play the piano, or ride a bicycle |
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Term
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Definition
| lasts a few seconds to a few minutes. Working memory is a store that holds important information in the mind for brief period of time. It enables us to retain a piece of sensory information just long enough to plan a response. |
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Definition
| The kind of memory that most people think of as memory hold the names of this and people, occurrences, events, and other pieces of fact for periods of time ranging from days to a lifetime. |
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Term
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Definition
is a region of the limbic system that seems to be involved in declarative memory. Removal of the hippocampus in humans erases memories going over the few months before surgery.
Long-term memory, from many years ago, however, remains intact. Further, there is loss of the ability to form new long-term memories. Therefore, it is believed that declarative memories are first stored in the hippocampus as short-term memories. After time, there is reshuffling and reorganization of the information and it is placed into more stable long-tem memory banks in other brain location. |
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Term
| Hypothalamus (the suprachiasmic nucleus) |
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Definition
| The times when we fall asleep and wake up seem to be set by a biological master clock located in one of the thenuclei of the hypothalamus (the suprachiasmatic nucleus). Its activity can be affected by expsure to light and darkness, and the gene for the master clock regulator has been cloned. |
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Term
| Neurotransmitters of sleep |
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Definition
| serotonin, norepinephrine and acetylcholine |
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Term
| Electrodes measuring sleep activity |
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Definition
1) brains - the electroencephlogram or EEG
2) eyes - the eletrooculogram or EOG
3) skeletal muscles - the electromyogram or EMG |
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Term
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Definition
| an active period marked by intense activity with the brain accompanied by dreaming, coupled with burst of eye mocements but also a strange motor paralysis affecting the trunk and limbs. |
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Term
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Definition
| a sleeper alternates between period REM and slow-wave sleap. Slow-wave sleep typically occupies a total of three-quarters of our sleep time and has four stages. The REM episodes punctuate slow-wave sleep, and occur about every 90 min. The later REM periods become longer (up to 30 minutes or more) |
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Term
| REM sleep characteristics |
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Definition
| REM occupies about a quarter of our total sleep time, and coincides with a time of dreaming and arousal of the sexual organs. If we are awakened from REM sleep, dreams can be easily recalled. |
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Term
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Definition
| starts with a flurry of activity in the pons and neighboring midbrain regions, which send signals to the thalamus, which relays them to the cerebral cortex and creates dreams. The onset of REM sleep seems to be associated with high levels of acetylcholine in the brain. Simultaneously, signals from the pons descend the spinal cord, and shut down spinal motor neurons to cause a kind of paralysis. This does not affect the eyes, but may serve to “free” the brain to create dreams and prevent the body from jumping out of bed to act out these dreams. |
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Term
| Slow-wave sleep Alpha-rythms |
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Definition
| is characterized by large, slow brain waves, normally comes first and is quieter than REM sleep. Blood pressure drops, heart rate and metabolism slow. Unlike REM sleep, slow-wave sleep is associated with low waves of acetylcholine in the brain. Slow-wave sleep has four stages, each progressively deeper and each characterized by progressively slower frequencies in the EEG and higher voltage activities. At first, the brain produces steady, small electrical waves called alpha-rhythms. |
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Term
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Definition
Stage 1 - the EEG irregular and variable waves. Occasionally we see images and may be startled awake by a hypnic myoclonia, a muscle contraction associated with imagery
Stage 2 - The EEG shows a pattern of largerwaves with sudden bursts of activity (sleep spindles) Stage 3 - The EEG has larger and slower waves. Stage - The EEg shows very large waves, and they have a slow, jagged pattern (delta-wave sleep). |
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Term
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Definition
| as opposed to normal dreams that occur in REM sleep, they generally occur in Stages 3 and Stage 4. The need for REM and Stage 4 slow-wave sleep declines during childhood and adolescence. |
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Term
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Definition
consist of three masses of gray matter of gray matter in the cerebrum and two in the midbrain
The cerebral structures include:
-caudate nucleus
-putamen
-globus pallidus
The midbrain components of the basal ganglia are as follows:
-subthalmic nucleus
-substantia niagra |
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Term
| Input to the Basal Ganglia |
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Definition
| The basal ganglia receive major input from wide areas of the cerebral cortex. |
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Term
| Output of the Basal Ganglia |
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Definition
Most of the output of the basal ganglia via the thalamus back to the cerebral cortex, much of it to areas that are involved with motor function.
-the basal ganglia play a dominant role in movement. |
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Term
| Function of basal ganglia action selection |
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Definition
Different parts of the basal ganglia seem to facilitate movements, while others suppress them, or tone them down. This balance between facilitation and inhibition has an importanct bearing on the role of the basal ganglia in action selection.
Any increase in facilitation or inhabitation cold affect motor activity in the direction of either an increase or decrease in the motor out put of the cerebral cortex. |
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Term
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Definition
parts of the basal ganglia that are involved in facilitating movements are damaged
-slowness in movements
-difficulty starting movements
-arms do not swing
-facial expressions do not change |
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Term
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Definition
Huntingtons is characterized by hyper activity. Those parts of the basal ganglia that normally suppress overactivity of movement seem to have been damaged in some way.
GABA-ergic neurons may be affected in the early stages of the disease. |
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