Week One: Brain Development and the Environment (page
208-220)
● Neuroplasticity refers to the lifelong changes in the structure of the brain that accompany
experience. Brain can be molded into different forms. Responsive to external events and
internal events (such as hormones, injury and abnormal genes)
● Hebb (1947) Rat Study: allowed young lab rats to live in his kitchen vs a control group of
lab-only rats. Home-rats performed better at intelligence tests/ mazes compared to
lab-only rats. Concluded that intelligence was due to experience.
● Enriched Environment, Enhanced Development: A. a complex housing environment for a
group of about six rats. The animals have an opportunity to move about and interact with
toys that are changed weekly.. B. Representative neurons from the parietal cortex of a
laboratory-housed rat. The neuron on the right is more complex and has about 25%
more dendritic space for synapses
● Increased number of synapses → increased sensory processing in a complex and
stimulating environment.
● The loss of plasticity does not mean that the adult human brain becomes fixed and
unchangeable. Doubtless the brains of adults are influenced by exposure to new
environments and experiences, although probably more slowly and less extensively than
children’s brains.
● Chemoaffinity hypothesis:Proposal that neurons or their axons and dendrites are drawn
toward a signalling chemical that indicates the correct pathway. Sperry (1963) suggested
that specific molecules exist in different cells in the various regions of the midbrain,
giving each cell a distinctive chemical identity.
● Amblyopia: A condition in which vision in one eye is reduced as a result of disuse,
usually caused by a failure of the two eyes to point in the same direction
● Critical Period: Developmental “window” during which some event has a long-lasting
influence on the brain; often referred to as a sensitive period
● Imprinting: Process that predisposes an animal to form an attachment to objects or
animals at a critical period in development
○ Lorenz’s study: goslings!
● Romanian Orphans (1970s): findings on this population have shown that the lack of
stimulation hampered normal brain development
● Masculinization: Process by which exposure to androgens (male hormones) alters the
brain, rendering it to identifiably male.
● Time-dependant effects: In the rat, damage to the frontal cortex on the day of birth leads
to development of cortical neurons with simple dendritic fields and a sperse growth of
spines in the adult. In contrast, damage to the field at 10 days of age leads to the
development of cortical neurons with expanded dendritic fields and denser spines than
normal adults.
, Week Two: Chapter 3; Internal Structure of a Cell (87-90) &
Genes, Cells and Behaviour (98-106)
Internal Structure of a Cell
● The characteristics of cells are determined by their proteins
Elements and Atoms
● Most living cells’ composition: oxygen, carbon & hydrogen
● An atom is the smallest quantity of an element that retains the properties of that element
● Has a nucleus that contains neutrons and protons
● Neutrons are neutral in charge
● Protons carry a positive charge (+)
● Electrons, that orbit, carry a negative charge (-)
● Ordinally, an atom is electrically neutral due to the equal amount of positive and negative
charges. However, can give up or gain electrons which alters the charge.
● This results in an ion.
● Ion formation: Ions are formed by the addition or loss of electrons
● Allows interaction
Molecules
● When atoms bind together, they form molecules.
● Molecules: the smallest unit of a substance that contain all that substance’s properties
Parts of a Cell
208-220)
● Neuroplasticity refers to the lifelong changes in the structure of the brain that accompany
experience. Brain can be molded into different forms. Responsive to external events and
internal events (such as hormones, injury and abnormal genes)
● Hebb (1947) Rat Study: allowed young lab rats to live in his kitchen vs a control group of
lab-only rats. Home-rats performed better at intelligence tests/ mazes compared to
lab-only rats. Concluded that intelligence was due to experience.
● Enriched Environment, Enhanced Development: A. a complex housing environment for a
group of about six rats. The animals have an opportunity to move about and interact with
toys that are changed weekly.. B. Representative neurons from the parietal cortex of a
laboratory-housed rat. The neuron on the right is more complex and has about 25%
more dendritic space for synapses
● Increased number of synapses → increased sensory processing in a complex and
stimulating environment.
● The loss of plasticity does not mean that the adult human brain becomes fixed and
unchangeable. Doubtless the brains of adults are influenced by exposure to new
environments and experiences, although probably more slowly and less extensively than
children’s brains.
● Chemoaffinity hypothesis:Proposal that neurons or their axons and dendrites are drawn
toward a signalling chemical that indicates the correct pathway. Sperry (1963) suggested
that specific molecules exist in different cells in the various regions of the midbrain,
giving each cell a distinctive chemical identity.
● Amblyopia: A condition in which vision in one eye is reduced as a result of disuse,
usually caused by a failure of the two eyes to point in the same direction
● Critical Period: Developmental “window” during which some event has a long-lasting
influence on the brain; often referred to as a sensitive period
● Imprinting: Process that predisposes an animal to form an attachment to objects or
animals at a critical period in development
○ Lorenz’s study: goslings!
● Romanian Orphans (1970s): findings on this population have shown that the lack of
stimulation hampered normal brain development
● Masculinization: Process by which exposure to androgens (male hormones) alters the
brain, rendering it to identifiably male.
● Time-dependant effects: In the rat, damage to the frontal cortex on the day of birth leads
to development of cortical neurons with simple dendritic fields and a sperse growth of
spines in the adult. In contrast, damage to the field at 10 days of age leads to the
development of cortical neurons with expanded dendritic fields and denser spines than
normal adults.
, Week Two: Chapter 3; Internal Structure of a Cell (87-90) &
Genes, Cells and Behaviour (98-106)
Internal Structure of a Cell
● The characteristics of cells are determined by their proteins
Elements and Atoms
● Most living cells’ composition: oxygen, carbon & hydrogen
● An atom is the smallest quantity of an element that retains the properties of that element
● Has a nucleus that contains neutrons and protons
● Neutrons are neutral in charge
● Protons carry a positive charge (+)
● Electrons, that orbit, carry a negative charge (-)
● Ordinally, an atom is electrically neutral due to the equal amount of positive and negative
charges. However, can give up or gain electrons which alters the charge.
● This results in an ion.
● Ion formation: Ions are formed by the addition or loss of electrons
● Allows interaction
Molecules
● When atoms bind together, they form molecules.
● Molecules: the smallest unit of a substance that contain all that substance’s properties
Parts of a Cell
