bio bases part 1

WHAT IS “BIOPSYCHOLOGY”
• “the branch of psychology that studies the biological foundation
of behavior, emotions, and mental processes” – (Pickett, 2000)
• Brain’s impact on Affect, Behavior, Cognitions
A—Affect (mood, emotion)
B—Behavior (actions)
C—Cognition (thoughts, thinking abilities)

▪ Generalization: Explaining behavior using general principles based on
multiple observations
▪ Reductionism: Explaining behavior in terms of simpler, more
elementary processes

Holism: Explaining behavior using complex systems, not smaller
components (i.e., the whole is greater than the sum)

PHYSIOLOGICAL PSYCHOLOGY
• Study of neural mechanisms of
behavior through direct manipulation
and recording of the brain in controlled
experiments
• Uses animal models

PSYCHOPHARMACOLOGY
• Study of effects of drugs on brain and behavior
Study the effects of psychoactive drugs

NEUROPSYCHOLOGY
• Study of psychological effects of brain damage in human patients

PSYCHOPHYSIOLOGY
• Study of relationship between
physiological activity and psychological
processes in humans
 EEG
 Muscle tension
 Eye Movement
 Heart rate/blood pressure
 Skin conductance

COGNITIVE NEUROSCIENCE
• Study of neural basis of cognition
• Thought, memory, attention, perception
• Tools of the trade include:
Functional brain imaging
Brain imaging (fMRI) showing occipital activity

COMPARATIVE PSYCHOLOGY
• Study of general biology of behavior
• Compare different species to understand evolution, genetic,
and adaptiveness of behavior
• In lab or in natural environment (ethological research)

Neurons and Supporting Cells
• Neurons (nerve cell)
• Reception, conduction, and transmission of electrochemical signals
• Interconnected (1 neuron can receive signals from 100)
• Delicate
• Glial Cells
• Physical, structural support for neurons
• Human brain contains about 86 billion neurons and up to 100
billion glial cells

Types of neurons
• Multipolar
• Bipolar
• Unipolar
• Anaxonic

Glia
• Glia = nerve glue
• Types of glial cells:
• Oligodendrocytes
• Schwann cells
• Microglia
• Astrocytes

Oligodendrocytes
• Functions:
• Support axons
• Produce myelin sheath =
lipid surrounding axon;
prevents messages from
spreading
• Insulates axon
• Bare portion of axon

Schwann Cells
• Functions same as
oligodendrocyte,
but in peripheral NS
• Support axons
• Provide myelin

Microglia
• Smallest type of glia
• Functions:
• Phagocytosis - glial cells engulf and digest other cells or debris
• Protect brain from invaders
• Inflammatory response

Astrocytes
• “Star cell”
• Functions
• Controls the Blood-Brain Barrier
• Send/receive signals from neurons, other glial cells
• Control maintenance of synapses
• Modulate neural activity

Human nervous system
• Central Nervous System (CNS)
• Peripheral Nervous System (PNS)

Sending messages to or away from the CNS
• Sensory (afferent) neuron
• Detects changes in external or internal
environment
• Motor (efferent) neuron
• Located within CNS; controls muscle
contraction or gland secretion
• Interneuron
• Located entirely within CNS

Somatic Nervous System
• Receives sensory information from
sensory organs and controls
movement of muscles
• Control over spinal and cranial
nerves
• Spinal nerves
• Cranial nerves

• Sympathetic
• Energy expenditure
• “Fight or Flight”
• Nerves concentrated small of the
back and chest area of spinal
cord
• Parasympathetic
• Energy conservation
• “Rest and digest”
• Nerves concentrated in cranial
and lower back region of the
spinal cord

CNS Protection
• Meninges
• Dura mater
• Arachnoid membrane
• Pia mater

Cerebrospinal fluid (CSF) – a clear fluid that surrounds brain and
spinal cord
• Ventricular system
• Lateral ventricles
• 3 rd ventricle
• 4 th ventricle
• Choroid plexus – protrudes into ventricles and produces CSF

CNS Protection
• Blood-Brain Barrier (BBB)
• Impedes passage of many
toxic substances from
blood to brain
• Capillaries tightly lined
• Area postrema = region of
medulla that controls vomiting
• Selectively permeable

Neuroanatomical Directions

Embryological divisions of the brain

Telencephalon
• Largest division, contains
• cerebral cortex,
• limbic system, and
• the basal ganglia
• Functions
• Initiates voluntary movement
• Interprets sensory input
• Mediates complex cognitive functions
(from last class)

Cerebral Cortex
• Many convolutions
• Increase surface area without
increasing volume
• Fissures
• Sulci
• Gyri

The Evolution of the Human Brain and
Nervous System
• Natural selection and evolution
• Natural selection favors the organism with the highest degree of fitness
• Evolution of the nervous system
• Vertebrates, or chordates, are animals with spinal columns and real brains
• Evolution of the human brain
• Brain development occurred very quickly

Cerebral Cortex
• 2 hemispheres
• Corpus callosum – band of
axons that connects 2
hemispheres of the brain
• 4 Lobes
• Divided by central and
lateral fissures
• Frontal
• Parietal
• Temporal
• Occipital

The Basal Ganglia System
• Located beneath anterior portion of
lateral ventricle
• Control of movement
• Regions
• Striatum is comprised of
• Caudate
• Putamen
• Globus Pallidus
• Nucleus accumbens (part of ventral
striatum)