9.5

• A catalogue of the proteins in different cell types.

  Proteome
• Its development is believed to be largely responsible for the course of human cognitive development, which occurs over the same period.

  Prefrontal Cortex
• Four types of cognitive functions of the prefrontal cortex:

  Working Memory, planning and carrying out sequences of actions, ) inhibiting responses that are inappropriate in the current context but not in others, following rules for social behavior
• Children tend to make this perseverative error between about 7 and 12 months, but not thereafter.
• Perseveration is the tendency to continue making a formerly correct response when it is currently incorrect.
• An important feature of the effects of experience on development is that they are time-dependent.
• If it is absolutely essential (i.e., critical) for an experience to occur within a particular interval to influence development, the interval is called a critical period.
• If an experience has a great effect on development when it occurs during a particular interval but can still have weak effects outside the interval, the interval is called a sensitive period.
• Most research on the effects of experience on the development of the brain has focused on sensory and motor systems— which lend themselves to experiential manipulation.
• Two general manipulations of experience:

  sensory deprivation and sensory enrichment.
• Study on sensory deprivation: Rats reared from birth in the dark were found to have fewer synapses and fewer dendritic spines in their primary visual cortex.
• Rats reared in the dark, as adults they were found to have deficits in depth and pattern vision.
• Rats that were raised in enriched (complex) group cages rather than by themselves in barren cages were found to have thicker cortex, with more dendritic spines and more synapses per neuron
• Study of Sensory deprivation in Human Babies with cataracts: When the cataracts were removed between 1 and 6 weeks after birth, their vision was comparable to that of a newborn. Thereafter, some aspects of vision improved quickly, but some visual deficits persisted into adulthood.
• Depriving one eye of input for a few days early in life has a lasting adverse effect on vision in the deprived eye, but this does not happen if the other eye is also blindfolded. When only one eye is blindfolded, the ability of that eye to activate the visual cortex is reduced, whereas the ability of the other eye is increased. By this the _______________ occurs.

  Ocular Dominance
• True or False: Ocular Dominance is an example of a critical period, as opposed to a sensitive period, because during adulthood the effect still occurs but requires longer periods of monocular deprivation

  False, Sensitive Period
• True or False: Surgically attaching the inputs of one sensory system to cortex that would normally develop into the primary cortex of another system leads that cortex to develop many, but not all, characteristics typical of the newly attached system.

  True
• True or False: An adult brain does not continue to grow and develop.

  False
• True or False: Neurogenesis does not occur in adults.

  False
• True or False: In rats, neurogenesis occurs in its hippocampus, then, new neurons are also continually generated in the subventricular zone.

  True