nervous system

side of brain controls left side of body, left side of brain controls _ side of body.

Right side of brain controls left side of body, left side of brain controls right side of body.

Functions of the brain.

• Maintenance of homeostasis - Higher mental functioning

What are gyri?

Folds (i.e ridges)

What are sulci?

valleys

What are fissures?

Deep valleys

What are lobes?

Different areas of the brain confined by fissures/sulci

What part of the brain contains gray and white matter?

Cerebrum (aka cerebral cortex)

The outer layer of the cerebrum (or cerebral cortex) is made up of and the underlying (inner layer) is made up of .

Gray matter & white matter

What is gray matter made up of? What is its function?

• Nerve cell bodies - Interneurons - Unmyelinated axons Function: Integrate information

What is white matter made up of? What is its function?

• Made of myelinated nerve tracts Function: Allows for communication between various areas of the brain over long distances

functions of the cerebrum

• thinking, sensing, emotions, memory conscious (voluntary) part of the brain - Accounts for 83% of the total brain weight

How many lobes is the cerebrum divided into? Name them.

4.

What divides the cerebrum into 4 lobes?

Fissures (deep groove)

Where is the primary motor cortex located?

In the cerebral cortex in the frontal lobe

Where is the somatosensory receptor located?

In the parietal lobe on the cerebral cortex

Function of the primary somatosensory cortex?

Receives sensory information from the body

Function of the primary motor cortex area?

Controls skeletal muscle

What is the association area?

Communicate with other parts of the brain. - Analyze and act on sensory input Once the sensory information has been interpreted, the information is sent to the prefrontal cortex. Predicts consequences of various responses and decides the best option.

What are the areas of the brain specialized in language abilities?

1. Broca's area 2. Wernicke's area 3. Angular Gyrus

What is the Broca's area?

Essential for speech (talking) - People with damage to Broca's area have speech deficits because they have problems in production of language output They can still read and understand language though.

True or False? People with damage to the Broca's area cannot read not understand language.

False. They can read and understand, but cannot talk.

What is Wernicke's area? What is the consequence of damage to Wernicke's area?

Involved with the sensoty (NOT motor) aspects of language. Damage to Wernicke's area leads to an inability to speak sensibly. - Problems with processing of words/language input. - Can't understand spoken or written language

What is angular gyrus?

Believed to be essential for integrating spoken and written language.

Input from spoken language travels from:

Auditory cortex --> Wernicke's area = understanding

Written language input flows from:

The visual cortex --> the angular gyrus (=integrating) --> Wernicke's arra = processing

Speech commands (output) are formulated in:

Wernicke's area travel --> Broca's area (=generating) then to --> primary motor cortex = speech

How does a word get repeated?

Auditory cortex --> Wernicke's area --> Broca's area --> motor cortex area

How does a written word get spoken?

Angular gyrus --> Wernicke's area --> Broca's area --> motor cortex

What is the diencephalon made up of?

Thalamus, Hypothalamus & epithalamus

Function of thalamus

Relays almost all sensory impulses to the cerebral cortex. --> Transfers impulses to the correct part of the cortex for interpretation. Provides crude perception of touch, pressure, pain and temperature. They are sensory Functions in cognition and awareness.

Function of hypothalamus

Serves as a center for emotions. Contributes to the control of: - Body temperature - Heart rate - Breathing rate - Eating - Drinking - Helps maintain waking state - Establishes patterns of sleep

Function of epithalamus

• Houses the pineal body/ gland (an endocrine gland) - Pineal gland secretes melatonin - Function in sleep/wake cycle - Includes the choroid plexus (forms cerebrospinal fluid)

The parts of the brain stem are:

1. medulla 2. Pons 3. Midbrain

What is the midbrain composed of?

Tracts of nerve fibers

Function of midbrain

• Relays motor impulses from the cerebral cortex to the pons • Relays sensory impulses from the spinal cord to the thalamus – Processes information about sights and sounds and controls reflex responses to these stimuli

What are pons composed of?

Fiber tracts

function of pons

Involved in assisting the medulla in the control of breathing

What is the medulla oblangata composed of?

Fiber tracts

Functions of medulla oblangata

Contains important control centers: - Heart rate - Blood pressure regulation - Breathing - Swallowing - Vomiting

What is the Reticular Activating System (RAS)?

Filters sensory information. - Filters out repetitive/familiar stimuli not dangerous for you: clothing pressure, sound of rain. - Filters out the daily normal activities from the dangerous/unfamiliar activities - Transmits important info to the cerebral cortex Activates the cerebral cortex - Keeps you alert and awake - When you sleep, RAS inhibited = unconsciousness - Conscious activity in the cerebral cortex stimulates the RAS

What filters out repetitive/familiar stimuli not dangerous for you?

Reticular activating system (RAS)

The hindbrain consists of these three: , _& _.

Includes cerebellum, pons & medulla oblangata

What is the function of the cerebellum?

• Compares intended movements with what is actually happening • coordinates complex, skilled movements • Regulates posture and balance

What is the limbic system?

Responsible for basic psychological drives, instincts and emotions. - Electrical stimulation of certain areas of the limbic system can cause intense sensations of pleasure, pain, or rage.

What system plays a role in forming memory?

The limbic system

The limbic system plays a role in forming memory. It takes place in two stages. What are they?

• Short-term memory: – holds a small amount of information for a few seconds / minutes • Long-term memory – stores limitless amounts of information for hours / days / years

What is hippocampus?

transfer of short-term memory to long-term memory.