Psychology2016

90 CHAPTER 2

From the Bottom Up: The Structures of the Brain

2. 10 Identify the different structures of the hindbrain
   and the function of each.

• The medulla is at the very bottom of the brain and at the top
  of the spinal column. It controls life-sustaining functions such
  as breathing and swallowing. The nerves from each side of the
  body also cross over in this structure to opposite sides.


• The pons is above the medulla and acts as a bridge between
  the cerebellum and the cerebrum. It influences sleep, dreaming,
  arousal, and coordination of movement on the left and right
  sides of the body.


• The reticular formation runs through the medulla and the pons
  and controls our general level of attention and arousal.


• The cerebellum is found at the base and back of the brain and
  coordinates fine, rapid motor movement, learned reflexes, pos-
  ture, and muscle tone. It may also be involved in some cognitive
  and emotional functions.

2. 11 Identify the structures of the brain that are
   involved in emotion, learning, memory, and motivation.

• The limbic system consists of the thalamus, hypothalamus,
  hippocampus, and amygdala.


• The thalamus is the relay station that sends sensory information
  to the proper areas of the cortex.


• The hypothalamus controls hunger, thirst, sexual behavior, sleep-
  ing and waking, and emotions. It also controls the pituitary gland.


• The hippocampus is the part of the brain responsible for the for-
  mation of long-term declarative memories.


• The amygdala controls our fear responses and memory of
  fearful stimuli.

2. 12 Identify the parts of the cortex that process
   the different senses and those that control movement
   of the body.

• The cortex is the outer covering of the cerebrum and consists of
  a tightly packed layer of neurons about one tenth of an inch in
  thickness. Its wrinkles, or corticalization, allow for greater corti-
  cal area and are associated with greater brain complexity.


• The cortex is divided into two cerebral hemispheres connected
  by a thick band of neural fibers called the corpus callosum.


• The occipital lobes at the back and base of each hemisphere pro-
  cess vision and contain the primary visual cortex.


• The parietal lobes at the top and back of the cortex contain the
  somatosensory area, which processes our sense of touch, tem-
  perature, and body position.
  
  
  • The temporal lobes contain the primary auditory area and are
    also involved in understanding language.
  
  
  • The frontal lobes contain the motor cortex, which controls the
    voluntary muscles, and are also where all the higher mental
    functions occur, such as planning, language, and complex deci-
    sion making.
  
  
  
  

   2. 13 Name the parts of the cortex that are responsible
  
   for higher forms of thought, such as language.
  
   - Association areas of the cortex are found in all the lobes but par-
  
      ticularly in the frontal lobes. These areas help people make sense
  
      of the information they receive from primary sensory areas and
  
      the lower areas of the brain.
  
   - A region called Broca’s area in the left frontal lobe is critical in
  
      the production of fluent, understandable speech. If damaged,
  
      the person has Broca’s aphasia, in which words will be halting
  
      and pronounced incorrectly.
  
   - An area called Wernicke’s area in the left temporal lobe is
  
      important for the understanding of language. If damaged, the
  
      person has Wernicke’s aphasia, in which speech is fluent but
  
      nonsensical. The wrong words are used.
  
   2. 14 Explain how some brain functions differ between
  
   the left and right hemispheres.
  
   - Studies with split-brain patients, in which the corpus callosum
  
      has been severed to correct epilepsy, reveal that the left side of
  
      the brain seems to control language, writing, logical thought,
  
      analysis, and mathematical abilities. The left side also processes
  
      information sequentially.
  
   - The right side of the brain processes information globally and
  
      controls emotional expression, spatial perception, recognition of
  
      faces, patterns, melodies, and emotions. Information presented
  
      only to the left hemisphere can be verbalized, but information
  
      only sent to the right cannot.

  
  

Applying Psychology to Everyday Life: Paying

Attention to Attention-Deficit/Hyperactivity

Disorder

2. 15 Identify some potential causes of attention-deficit/
   hyperactivity disorder.

• ADHD is often diagnosed in children but may persist into adult-
  hood. Multiple causes are possible, including genetic and envi-
  ronmental factors and several differences in brain structure and
  function.