Study Guides (390,000)
CA (150,000)
UTSG (10,000)
Study Guide

HMB200H1 Study Guide - Comprehensive Final Exam Guide - Gamma-Aminobutyric Acid, Amygdala, Synapse


Department
Human Biology
Course Code
HMB200H1
Professor
Franco Taverna
Study Guide
Final

This preview shows pages 1-3. to view the full 27 pages of the document.
HMB200H1

Only pages 1-3 are available for preview. Some parts have been intentionally blurred.

Only pages 1-3 are available for preview. Some parts have been intentionally blurred.

HMB: LECTURE ; DOES THE BRAIN CHANGE ITSELF?
Principles of Neurosci 1
The Ns function is to produce movement w/I the perceptual world the brain creates
History
Rene Descartes believed nerves were hollow tubes filled with liquid
o inspired by mechanical statues and got the idea of reflexive behaviour from them
o Theorized that humans and animals behaved the same way
o Stimuli vibrate spirits (fluid) in our nerves and that is sent to the brain and back down to the muscles
(reflex arc)
Descartes was a dualist so he believed the mind (spiritualism) and body (materialism) were separate
o Materialism: our body was fixed and we used it to create simple behaviours and reflexes
o Rational soul in penal gland ca modify those movements (spiritualism = change)
Modern Materialism
Spinal motor neurons send nerve impulses to synapse on muscle cells
Muscle activation occurs through Ach
o Released at the axon terminal of muscle fibers called muscle end plates
o Muscle generates AP to contract
o Nmj was the first synapse studied
Spinal motor neurons are activated by cortical neurons whose axons deceased down the anterior spinal tract
Fibers entering dorsal root carry sensory information from sensory receptors while ventral root carry motor
information to muscles
Motor cortex: cortical motor neurons that connect to the brainstem or spinal cord
Brainstem: can execute specific behaviours
The spinal cord can execute simple reflex motor actions
Spinal cord and Brainstem
Spinal reflexes can still function even though the spinal cord is severed from the brain
o Paralyzed limbs may spasm also if given postural support people can imitate walking movement
o Brainstem helps to produce complex patterns of behaviour (e.g. walking, breathing)
Organizes adaptive movements
Cerebral palsy: voluntary movements become difficult to make whereas conscious
behaviour controlled by the cortex may still remain intact
Caused by brainstem trauma
Principles of Neurosci 4
The NS functions on multiple levels
Each addition of new levels ads new behavioural complexity without discarding the previous levels
o This confers adaptive functions
Wilder Penefield confirmed the role of the primary motor cortex
o Discovered mid surgery that electrical stimulation causes movement and mapped the brain using this
method
Motor Cortex
Topographic organization: neural spatial representations of the body parts activated by the brain religion
o There is not a 1:1 correspondence between brain and muscle. But with body parts
Proportional representation: in the motor cortex the body parts with most dexterity get the most cortical
representations in the brain
Homoulus: the proportional representations of the human body according to the sensory and motto cortex
o Sensory and motor cortex are not directly connects also the motor cortex is in front of the sensory
cortex
Motor cortex triggers categories not individual movements
o Activated by the premotor cortex
o Represents a repertoire of fundamental movements (e.g. reaching, jumping, bring arm up)
Primary motor cortex (M1): encode direction, force, and speed of movement
find more resources at oneclass.com
find more resources at oneclass.com
You're Reading a Preview

Unlock to view full version

Only pages 1-3 are available for preview. Some parts have been intentionally blurred.

Principles of Neurosci 6
Brian systems are organized hierarchically and in parallel
CNS comprises multiple levels of function and these levels must be extensively interconnected to integrate
their processing and produce unified perception or movements
All parts of the brain project to the frontal lobe (executive function) and most input comes form association
area (parietal lobe) which in turn gets info from a bunch of regions and projects if forward
Frontal lobe: executive function
Partial lobe: sensory integration
Temporal lobe: A1, T1, O1 and medial temporal lobe
Occipital: visual processing
From our retina's our optic nerve can go to two pathways: genicostriate or tectopulvinar
Hubel and Wiesel said the V1 was a feature detector which means is it sensitive to orientation and position
Principle of Neurosci 1 (con’t)
The brain produces a reality that is adaptive for the species to survive
To form a unified perception senses stimuli in all modalities arrives in the brain after 3-4 synapses and info is
added at every step (re-coded)
Info may interact at each parallel (e.g. McGurk effect results from unified perception of what we see and
hear)
The brains primary function is to produce movement and to do so it must:
1.
Reactive info from the world (sensation)
2.
Interrelate sensory info to create a subjective experience (perception)
3.
Produce movement
Reductionist approach: defines variable as specially as
possible but like principle 6 the subsystems of the brain
are organized into multiple parallel levels, your conscious
experience is always unified
The brain is built by nature but also influenced by nature
Principles of Neurosci 2
Neuroplasticity: the hallmark of NS functioning
o Necessary for memory and learning
o The potential of the nervous system to physically
or chemically change to enhance the brains
adaptability
o When monkeys motor cortex controlling one of
their hands was destroyed the cortical
representations shirked
o Behaviour + feedback = adaptability
The brains function is to perceive and act
find more resources at oneclass.com
find more resources at oneclass.com
You're Reading a Preview

Unlock to view full version