Midbrain and Forebrain Flashcards
(28 cards)
What is the role of the midbrain in humans?
In humans, the midbrain receives basic auditory and visual stimuli and sends this information to other parts that can interpret it. It has become smaller over evolution as its functions are now controlled by other parts.
How do some species utilize the midbrain?
Some species control movements used in sexual behavior and fighting, and decrease sensitivity to pain. Birds of prey have larger and more complex midbrains used to fly and coordinate actions to hunt.
How do rabbits and dogs use their midbrain?
In rabbits and dogs, the midbrain is used for novel stimuli, such as pricking up their ears.
What is the largest part of the brain in mammals?
Mammals, particularly primates, have the largest forebrains. In humans, it is so large, it surrounds the midbrain and hides half the hindbrain from view
What is the cerebral cortex?
The cerebral cortex is the most obvious part of the brain, wrinkled in appearance, and is crucial for psychological functions.
What percentage of the brain’s volume does the cortex account for in primates?
In primates and complex mammals, the cortex accounts for more than half the brain’s volume, with 80% in humans.
What tasks does the cortex perform in mammals in comparison to non-mammels?
Tasks performed by the limbic system/midbrain in non-mammals are performed by the cortex in mammals.
What impact did human evolution have on the cortex?
More tasks started to be managed by the cortex, with subcortical structures like the midbrain acting more as relay stations.
What are the meninges?
The meninges are 3 layers that wrap around the brain: Dura (durable outer layer), Arachnoid (flimsy, resembles a spider web), and Pia mater.
What is a gyrus?
A gyrus is a ridge on the cerebral cortex and is always part of the brain that has a function.
What does precentral and postcentral gyrus refer to?
Precentral gyrus means it is before the sulcus, and postcentral means after the sulcus.
What is a sulcus?
A sulcus is the groove between ridges, also known as a fissure, and they have no functions.
What does the central fissure separate?
The central fissure separates the frontal lobe from the parietal lobe.
Whhere are subcortical structures?
Subcortical structures are hidden underneath the cortex.
What is the function of the thalamus?
Receive & relay station for all sensory input (except smell), performs simple analysis and passes results on to primary sensory cortex
Where is the hypothalamus located and what are its functions?
The hypothalamus sits below the thalamus
Functions: homeostasis, feeding, drinking, body temperature, and sex, controls much of the ANS especially the pituitary gland
What is the role of the basal ganglia?
There is a basal ganglia in the left
& right hemisphere.
Regulation and smoothing of movement; implicated in movement disorders like Parkinson’s and Huntington’s.
Where and what does the limbic system include and what are its functions?
The limbic system, located deep in the temporal lobe, includes the amygdala (expression of fear and anger) and the hippocampus (memory).
Where and what is the primary function of the occipital lobe?
Receives input from the eyes via the thalamus and contains the primary visual cortex.
Back of the brain
What is the role of the parietal lobe?
Important for spatial perception, receiving area for skin senses eg. touch.
Includes the postcentral gyrus
What is the primary function of the temporal lobe?
Receiving area for auditory information and memory; also processes smell.
What is the primary function of the frontal lobe?
Responsible for motor output and planning.
Includes the precentral gyrus, which maps onto movement of different parts of the body.
What are primary areas of the cortex responsible for?
Primary areas are responsible for very basic input (sensory) and output (motor) and send information to the corresponding association cortex.
What are association areas in the cortex?
Association areas are responsible for elaboration (higher functions) and making sense of the information.
