The document discusses the biological bases of behavior by summarizing the structure and function of the nervous system and brain. It notes that the nervous system consists of the central nervous system (CNS) and peripheral nervous system. The CNS contains the brain and spinal cord, with the brain being the supreme organ that controls thoughts, emotions, and motivations. The brain contains three main regions - the hindbrain, midbrain, and forebrain. The forebrain contains four major parts that control functions like emotion, memory, movement, sensory processing, and higher thought.

1. Biological Bases of Behavior
:Lecturer
Nadia Sbaih

2. • At the core of our thinking, feeling, and acting is
the nervous system.
• The nervous system is the physiological network
of intercommunicating cells that forms the basis
of our ability to perceive, adapt to, and interact
with the world.
• The brain is the supreme organ of the nervous
system and it is the organ that most directly
controls our thoughts, emotions, and
motivations.

3. • The Organization of the Nervous System
• The Central Nervous System (CNS)

4. • The nervous system consists of two main
parts, the central nervous system
• (CNS) and the peripheral nervous system

5. •The central nervous system has two parts:
•the brain and
•the spinal cord
• Both parts are encased in bone for protection
and further protected from shocks by
•cerebrospinal fluid which circulates throughout
the brain and the spinal cord.

8. The Structure and Functions of the
Brain
• The brain has three major regions:
hindbrain,
midbrain,
and forebrain.

9. The Hindbrain
• The hindbrain is the site of some of the most
primitive and basic functions that the brain
controls. It compromises the medulla
oblongata, the pons, and the cerebellum.

10. • The medulla oblongata is an elongated
structure at the point where the spinal cord
enters the skull and joins with the brain.
• It helps to keep us alive by entirely controlling
the heart rate and largely controlling
breathing, swallowing, and digestion

11. • The pons serves as a kind of relay station,
containing neurons that pass signals from one
part of the brain to another.

12. • The cerebellum
• controls bodily coordination, balance, and
muscle tone.

13. The Midbrain
•The midbrain is less important in mammals than in
nonmammals, where it is the main source of
control for visual and auditory information.
•In mammals these functions are mostly taken over
by the forebrain. But the midbrain does help to
control eye movements and coordination, and is
also important in controlling consciousness (sleep,
arousal), attention, cardiorespiratory function, and
movement.

14. The Forebrain
• The forebrain is the region located toward the
top and front of the brain.
• The largest area of the brain, it has four parts;
the limbic system, the thalamus, the
hypothalamus (often viewed as part of the
limbic system), and the cerebral cortex.

16. The Limbic System
• The limbic system is important to emotion,
motivation, and learning.

17. The hippocampus
• plays an essential role in memory function.

18. • Below the hippocampus is the amygdala,
which plays a role in emotion, including anger
and aggression.

19. • The septum is involved in anger and fear.

20. •
• The thalamus relays the incoming sensory
information to the appropriate region of the
cortex.

21. • The basal ganglia constitute a set of structures
close to the thalamus and hypothalamus that
are involved in control of movements as well
as in judgments and decisions that require
minimal amounts of thought.

22. • The hypothalamus, is roughly the size of a
kidney bean and controls water balance in the
tissues and bloodstream as well as many other
functions of the autonomic nervous system.

23. • The Cerebral Cortex and the Hemispheres

24. • The cerebral hemispheres and the cerebral
cortex together make up the cerebrum, that
essential part of the human brain that sets us
apart from other members of the animal
kingdom by allowing us a greater range of
psychological functioning and, in particular,
thought.

25. The cerebral cortex
• The cerebral cortex is actually the outer layer
of the two rounded halves of the brain, the
left and the right cerebral hemispheres
• Although the two hemispheres look similar,
they function quiet differently. The left
hemisphere is specialized for some kinds of
activity, the right for other kinds.

26. • Despite the general tendency for contralateral
specialization, the hemispheres do
communicate with each other.

27. The corpus callosum
• a dense body of nerve fibers, connects the
two cerebral hemispheres.

28. The Hemispheres of the Brain
• Broca’s area
• a structure in the left frontal lobe, is involved
in the movements of the mouth needed for
speech. It is also involved in our ability to
speak grammatically.

29. • Wernicke’s area
• also traced to an area in the temporal lobe of
the left hemisphere of the brain, is involved in
language comprehension
• It appears that roughly 90% of the adult
population has language functions
predominantly localized within the left
hemisphere.

30. The Four Lobes of the Brain
• The frontal lobe is the location of higher
thought processes, such as abstract
reasoning and motor processing.
• Somatosensory processing of sensations in the
skin and muscles of the body takes place in
the parietal lobe
• Auditory processing in the temporal lobe
• Visual processing in the occipital lobe