Overview of Behavioral Anatomy

& Addiction

The Nervous System

nervous system is responsible for communication between us and environment among regions of the body

coordinates and integrates information

regulates activity; maintains homeostasis

memory & consciousnessHistology slide of somebrain tissue

CNS PNS

Sensory Division afferent

sensory nerves to CNS

Motor Division efferent

motor nerves to muscles & glands

Autonomic NSinvoluntary

heart, smooth muscle, glands

Somatic NS

skeletal muscle

A nerve cellshowingdendrites andan incomingaxon.

D

A

D

(Another) histology slideillustratingthe physicallayout of somenerves in thebrain.

Some Important Parts of the Brain

Cognitive area

Limbic (another very important) System of the Brain

The limbic system isresponsible for generatingour emotional feelings (pleasure, frustration, anger) based on our cognitive interpretation of our environment

Substantia nigra

Caudate

PutamemGlobus Pallidus

Ventral tegmentalarea

Locus coeruleus

Basal Ganglia is part of the limbic system

Our sensory nerves inform our brain about our physical environment

Kinesthetic PerceptionSensory areas of the brain receive input from nerve fibers which originate from different types of receptors (touch, visual, auditory, pain, taste).

Sensory nerves originating from Pacinian corpuscles in the skin (mechanoreceptors) respond to touch.

Sensory nerves originating from proprioceptors

in the joints respond to “angle-specific pressure”

A-delta nerves originating from free nerve endings (Noci receptors) respond to tissue damage.

Primary (SI) and secondary (SII) sensory cortex involved with the localization of pain

Anterior portion of insular is most likely concerned with pain perception

All sensory information is relayed throughout different parts of the brain and our conscious interpretation of the stimuli generates a physical and emotional response which we “feel”:

body/joint position, body and/or limb movement, well-being, nausea, pain …

happy, sad, frustration, disappointment, joy, ecstasy, anger …

Our CNS response to stimuli also includes (selective) changes in the (autonomic) sympathetic and parasympathetic nerve pathways; selective changes based on our interpretation of the stimuli.

Sympathetic N.S.• Thoracic, Lumbar motor

nerves– synapse close to spinal cord

• Fight or flight – preservation of life– heart & skeletal muscle

stimulated blood pressure metabolism brain activity

– vegetative functions inhibited

Parasympathetic N.S.

• craniosacral motor nerves– synapse in wall of

organ

• vegetative functions– internal housekeeping,

recovery, rest G.I. activity• digestive organs

– inhibit brain & muscle

Learning and memory play a very important role in how we develop behaviors

Memory

A “memory” is not a discrete location in the brain made up of a cluster of cells which are independent of other cells.

A “memory” is actually comprised of a “pattern” of nerve-cell activities made up of interconnected nerve cells which are scattered throughout the cerebral cortex. These cells are in turn interconnected to all other brain cells.

Memory/Learning

We do not remember facts as discrete pieces of independent information.

We have memories of “facts” only in association with other memories.

We develop new memories only in association with existing memories.

Memory/Learning

New memories are created by rearranging existing patterns of activated nerve cells into new patterns of activity.

This process demands synthesis of new proteins in “some” nerve cells to modify their ability to be activated by other nerves and thereby create a new patterns of activation.

Learning

Parts of the brainthat are importantfor learning.

Learning

Hippocampus coordinatesenvironmental stimuliand activates existingmemory.

Learning

New memory is constructedbased on novel stimulus incomparison to existingmemory.

“Strength” of the memory isdependent on the frequencyand strength of the neural activity.

Learning & Memory

The new memory isactivated either throughthe “novel” stimulus orthrough the associatedmemory.

We remember facts as pieces of “information” in relation to other pieces of “information” which in turn are related to other …

Memory / Behavior

Sensory memories of physical movements are stored as patterns of neural activity in the cerebellum and are developed in much the same way as factual memories.

Memory / Behavior

All sensory inputs are coordinated by reticular formationand basal ganglia and transmitted to frontal cortex.

Sensory input is unconsciously compared to sensory memory and adjustments are made “as-you-go”.

Simultaneously, conscious image is compared consciously to conscious memory of what we should look like while we do it and we make conscious adjustments to mimic the conscious memory of the skill.

Integration of conscious and subconscious adjustments based on conscious and subconscious memories of the performance result in the actual performance.

The most basic connection between behavior and memory is that we desire to perform behaviors which produce responses that we want….if we can’t remember that a particular behavior resulted in a desirable outcome, there is little chance we will seek out to repeat the same behavior.

In addition, if a particular behavior results in an unpleasant experience, there is a strong likelihood that we will avoid that behavior.

On the other hand, if a behavior is not particularly pleasant, but does result in a highly desirable outcome, there is a high likelihood that the unpleasant behavior will be continued in order to get the pleasant payoff.

Memory, Learning & Behavior

Memory / Learning / Behavior

With greater pleasure, reinforcement can be developed more easily and quickly.

With greater activation of the memory & learning pathways during the behavior, the easier and faster the learning.

With more important desired behaviors, there is greater craving in their absence.