1. Brain Associations

2. Mirror Neurons
Neurons that fire when someone sees the same action done by another individual
“Mirrors” the behavior

3. Four Major Areas of the Brain
Cerebrum
Diencephalon
Brain stem
Cerebellum
The brain is located in the cranial cavity and is pinkish-gray, is delicate, has a soft consistency, and is divided into four major areas.
The primary source of energy for the brain is glucose.
Copyright © 2011, 2007 by Saunders, an imprint of Elsevier Inc. All rights reserved.

4. Cerebrum: Four Lobes Frontal lobe Parietal lobe Temporal lobe
Occipital lobe
The cerebrum is the largest part of the brain and is divided into the right and left cerebral hemispheres.
The corpus callosum, bands of white matter that form a large fiber tract, joins the two hemispheres and allows them to communicate with each other.
Each cerebral hemisphere has four major lobes that are named for the overlying cranial bones.
Copyright © 2011, 2007 by Saunders, an imprint of Elsevier Inc. All rights reserved.

5. Cerebrum: Markings Gyrus (convolution) Fissures (sulci) Central
Lateral
Longitudinal
The gyri (singular, gyrus), or convolutions, looks like speed bumps on the surface of the brain. By increasing surface area, they increase the amount of tissue available for thinking.
Fissures or sulci are grooves that separate the gyri. Of particular interest is the central sulcus, which separates the frontal lobe from the parietal lobe; it is an important landmark.
Ask students to examine Figure 10-11A. In what cerebral lobe is the precentral gyrus found? In what cerebral lobe is the postcentral gyrus found?
The precentral gyrus is found in the frontal lobe and the postcentral gyrus in found in the parietal lobe.
Copyright © 2011, 2007 by Saunders, an imprint of Elsevier Inc. All rights reserved.

6. Prefrontal Cortex (PFC)
Very most anterior part of cortex
Controls planning and thought
Thought to be the last to develop (XY 25 y.o.a)

7. Frontal Lobe “ The executive” oversees/monitors: Behavior Personality
Motor control
Most frontal lobe functions are associated with higher order intellectual functioning and motor activity.
What do you think might happen to a person who has sustained a severe injury to the frontal lobe?
Answers will include difficulty with memory, changes in personality and behavior, and impairment of intellectual and motor functioning. For example, a person might need to relearn reading.
Copyright © 2011, 2007 by Saunders, an imprint of Elsevier Inc. All rights reserved.

8. Frontal Lobe: Motor Activity
Primary motor area
Precentral gyrus
Frontal eye field
Motor speech area
Broca’s area
Produces speech not understanding speech
If a person suffers a stroke involving Broca’s area, why may she understand what you are saying but be unable to respond verbally?
The motor speech area (Broca’s area) deals with the physical aspects of producing speech, not cognitive issues such as understanding the meanings of words.
Copyright © 2011, 2007 by Saunders, an imprint of Elsevier Inc. All rights reserved.

9. Frontal Lobe: Motor Homunculus
Shows percentages of frontal lobe devoted to body’s motor activities
The homunculus represents the amount of brain tissue that corresponds to a motor function of a particular body part.
Each part of the body is controlled by a specific area of the primary motor cortex of the precentral gyrus. Complicated movements require large amounts of brain tissue.
Ask students to compare the size of the homunculus’s hands and feet. Why are the hands bigger than the feet?
The hand performs more complex movements that require more brain tissue.
One could also draw a similar homunculus on the postcentral gyrus to illustrate sensory function.

10. Other Cerebral Lobes Fronto-parietal cortex Parietal Temporal
Spatial attention
Location of mirror neurons
Parietal
Somatosensory area
Pain, pressure, touch, temp.
Gustatory area: taste
Temporal
Auditory cortex: hearing
Olfactory area: smell
Occipital
Visual cortex: sight
The parietal lobe contains the somatosensory area. This area interprets temperature, pain, pressure, light touch, and proprioception.
The temporal lobe contains the auditory cortex and the olfactory area. Information from the taste buds is interpreted in both the temporal and parietal lobes.
The occipital lobe contains the visual cortex.

11. Functions Spanning Cerebral Lobes
Speech areas
Span temporal, parietal and occipital lobes
Usually in left hemisphere
Wernicke’s area (helps translate thought into speech)
Association areas
Helps to interpret sensory information
Visual Association
Auditory, and somatosensory associations
Wernicke’s area is located in both the temporal and parietal lobes and is responsible for translating thought into words.
Explain why injury to the left hemisphere is much more likely to result in speech impairment than injury to the right hemisphere?
In most people, the speech centers are concentrated in the left hemisphere.
The primary visual cortex allows you to see an imagefor example, a tree. What additional information does the visual association area provide?
The visual association area allows you to interpret or apply meaning to the image, perhaps that it is an oak tree or that it needs water.

12. Diencephalon (2 heads) Thalamus: Hypothalamus:
helps with pleasantness vs. unpleasantness, some emotions
Hypothalamus:
Survival and enjoyment
Appetite, thirst
Hormone Regulation
Diurnal rhythms
Sleep cycles, rhythm throughout day
Reward cycle (eat, drink, sex)
There are two parts of the diencephalon, the thalamus and the hypothalamus.
The thalamus acts as a sensory pathway for information coming from the lower brain and the spinal cord to the sensory areas of the cerebrum. It is especially important with regard to pain sensation.
The hypothalamus sits above the pituitary gland and controls endocrine function. It is also the body’s thermostat and helps regulate autonomic functions.
Pineal gland???Melatonin???

13. Brain Stem Midbrain: reflex help with vision and hearing
Pons: breathing rate and rhythm
Medulla oblongata:
Vital center: HR, BP, Respiration
Emetic center: Vomiting
Reflex center
The midbrain contains nuclei that serve as reflex centers for vision and hearing.
The pons plays an important role in regulating breathing rate and rhythm.
The medulla oblongata descends through the foramen magnum as the spinal cord. It is called the vital center because it controls heart rate, blood pressure, and respiration. Its emetic center stimulates vomiting, either as a result of direct stimulation (e.g., fear, spinning, or distressing odors) or from indirect stimulation from the chemoreceptor trigger zone (CTZ), as in cancer chemotherapy.

14. Cerebellum “Tree of Life” Mediates reflexes Coordinates motor activity
Voluntary muscles
Evaluates sensory input
The primary responsibility of the cerebellum is the coordination of voluntary muscle activity. It produces a smooth, coordinated muscle response after integrating all the incoming information from many areas throughout the body.
It is also a major reflex center.

15. Structures Spanning Brain Divisions
Limbic system (cerebrum + diencephalon)
Sense of smell
Long-term memory
Emotional brain
Limbic system includes
Amygdala (almond): memory of emotional reactions; especially tuned for fear and anger
Hippocampus: emotion and memory, ANS
These three important structures are not confined to any one division of the brain. They overlap several areas.
The limbic system is a wishbone-shaped group formed by parts of the cerebrum and diencephalon.
The reticular formation is responsible for maintaining consciousness and activating the sleep-wake cycle. It also contains the gaze center.
The memory areas allow the recollection of thoughts and images. Many areas of the brain are responsible for memory.

16. Structures Spanning Brain Divisions
Reticular formation: Reticular activating system; sleep-wake cycle, consciousness, gaze center
Memory areas
Short-term memory
Few seconds or min.
Long-term memory
Days or years
The reticular formation is responsible for maintaining consciousness and activating the sleep-wake cycle. It also contains the gaze center.
The memory areas allow the recollection of thoughts and images. Many areas of the brain are responsible for memory.