Week4 Brain Flashcards
3 major divisions of the brain
Hindbrain, Midbrain, Forebrain
Describe hindbrain
-the lowest and most primitive level of the brain
-contains brain stem and cerebellum
Describe brain stem
-One of the oldest and most primitive aspects of the brain
-The medulla - enables heart rate & respiration to occur automatically
-The pons - helps to control vital functions, esp. respiration, also helps to regulate sleep, & acts as relay between the cerebellum & the cerebral cortex
Describe the cerebellum
The Cerebellum:
-control & coordination of muscular movement, plus learning & memory
- Responsible for precise timing & coordination of movement
-Damage to the cerebellum leads to severe motor disturbances (jerky, uncoordinated movements).
Cerebellum initiates movement (T/F)
False
Athletes and cats have more advanced cerebellum (T/F)
True
Describe the Midbrain
- Contains clusters of sensory & motor neurons
- The Reticular Formation: alerts higher centres of the brain that messages are coming & then either admit or block those messages
- It plays a role in consciousness, sleep & attention.
Describe the forebrain
The brain’s most recently evolved part
- Cerebrum: the major structure of the forebrain
- Consists of two large hemispheres that wrap around the brain stem
- Outer portion of the forebrain is covered by a layer of tissue, the cerebral cortex.
Where are thalamus and hypothalamus located?
Forebrain
Functions of thalamus
-organizes inputs from sensory organs
-routes them to the appropriate areas of the brain
Functions of hypothalamus
-involved in motivation & emotion
-controls hormonal secretions that regulate sexual behaviour, metabolism, & reactions to stress.
-involved in experiences of pleasure/displeasure (eg social behaviour, aggression, sleep, drinking)
Damage to thalamus can cause
hallucination (unable to distinguish reality and imagination)
Describe function of the Limbic System
Helps coordinate behaviours needed to satisfy motivational & emotional urges that arise in the hypothalamus
What does the limbic system contain
-Hippocampus: involved in forming, consolidating & retrieving memories
-Amygdala: involved in emotional behaviours (mainly fear and angry)—> Important for emotional memories
Damage to amygdala may cause
Difficulty to remember the emotional part of a memory
Hippocampus creates memories (T/F)
False
Describe the Cerebral Cortex
-Sheet of grey, unmyelinated cells that form the outermost layer of the human brain (80% of the human brain)
-wrinkly in appearance.
-Bulges called gyri
-Grooves are called fissures: folds in the cerebral cortex; allows greater surface area in a smaller space
-Fissures separate the brain into four lobes (frontal, parietal, occipital, & temporal)
Describe Motor Cortex
-Controls the 600 or more muscles involved in voluntary body movements
-Each hemisphere governs movement on the opposite side of the body
The size of body part is not directly proportional to our brain’s representation of them.
True as this relates to each body part’s significance to sensation and complexity of motion
Describe the Sensory Cortices
-Receives input from our sensory receptors
-Somatosensory cortex: receives sensory input that gives rise to our sensations of heat, touch, & cold and to our senses of balance and body movement
-Amount of area allotted is proportionate to sensitivity
Association Cortex
- Involved in many important mental functions, including perception, language, and thought
- Stimulation does not cause specific sensory or motor reactions
- Damage can cause disruption or loss of speech, understanding, thinking, & problem solving
Agnosia
The inability to identify familiar objects
The Frontal Lobes
29% of human brain; less in all other mammals
Least understood part of the brain
Damage can result in an inability to plan & carry out a sequence of actions
Involved in emotional experience
Prefrontal Cortex
For executive functions
