Introduction to Psychology

Dr.S.Nishan Silva

(MBBS)

Lets take a look at some words…..

Psychiatrist

Psychiatrist

Psychologist

Counselor

Friend

You

What is Psychiatry?

The branch of medicine that deals with the

diagnosis, treatment, and prevention of mental and

emotional disorders.

What is counselling?

Counselling is a  process that enables a

person to sort out issues and reach decisions affecting their life.

What is Psychology?• Psychology is the systematic study of human (and

animal) behavior.

• It is the study of how humans behave as they relate to their environment. 

• Psychology is also the study of how humans learn or adapt to their environment.

•  Psychology studies how the mind works and how the nervous system helps the organism to adapt successfully to its environment.

Difference between Psychiatry and Psychology

• Psychiatry is closely related to psychology, but is different because it is a specialization in medicine which hopes to understand and cure medical disease. The practice of psychiatry requires a MD. Psychiatry deals with the diagnosis, prevention, and treatment of mental illness.

Psychology vs. Psychiatry

• Clinical Psychology– a specialty in psychology – clinical psychologists– uses psychotherapy to treat psychological disorders

• Psychiatry– a specialty in medicine– psychiatrists– may prescribe medication and use psychotherapy

Why study psychology?

• “Everything psychological is simultaneously biological.”– Every thought, behavior, emotion,

perception, etc. is rooted in our biology, particularly our brain

– The brain is a “psychological organ” as well as a biological one

• Biological psychology: studies the link between our biology and our behaviors and mental processes– a.k.a. biopsychology,

neuroscience

Psychology’s Current Perspectives

Perspective Focus

Neuroscience How the body and brain create emotions, memories, andsensory experiences

Behavior How much our genes, and our environment, influence ourgenetics individual differences

Behavioral How behavior is learned

Evolutionary How nature selects traits that promote the perpetuation ofone’s genes

Psychodynamic How behavior springs from unconscious drives andconflicts

Cognitive How we encode, process, store, and retrieve information

Social-cultural How behavior and thinking vary across situations and cultures

History

Predict what will happenSystematically observe eventsDo events support predictions

Life Before Psychology

Philosophy asks questions about the mind: Does perception accurately reflect reality? How is sensation turned into perception?

Problem - No “scientific” wayof studying problems

Physiology asks similar questions about the mind

SCIENTIFICMETHOD

The field and study of psychology was truly born when Wilhelm Wundt established the first experimental psychology lab in Leipzig,

Germany in 1879.

Psychology Is Born

Wilhelm Wundt(1832-1920)

First Experimental Psych Lab (1879)First Experimental Psych Lab (1879)

Focuses on the scientific study of the mind.WW insists that Psych methods be as rigorous

as the methods of chemistry & physics.

University of LeipzigHarvard UniversityYale UniversityColumbia UniversityCatholic UniversityUniv of PennsylvaniaCornell UniversityStanford University

Wundt’s students start labsacross USA (1880-1900)

Behavior

Biological basis of behavior

• Depends on various processes in the human body. 

• The relation between these processes is regulated by the nervous system.

Stopping at the traffic lights…

Stopping at the traffic lights…

• Here is an example of what your body has to do in order to make you stop for a red traffic light. 

• First you have to perceive the light, which means that the light has to be caught by the eye. 

• The eye sends signals to the brain. 

Stopping at the traffic lights…

• The brain compares the signals with those received from the other eye and stores the signals temporarily in your memory. (You know you have to stop for the red light.)

• After that you have to push the brake pedal. To make this happen, your brains have to send a signal to the leg muscles to push the feet on the brake pedal.

Early Ideas of this….

Greeks• Linked mind with brain

• Hippocrates– Brain controls emotions,

thought & mental health

• Galen– Brain fluids responsible for

sensation, reasoning, memory & movement

Phrenology

• Bumps and depressions on skull = personality & character

• Flawed!Franz Gall

Galvanists

• 1786 Luigi Galvani

• Accidently demonstrated electrical basis of nerve impulses

Brain Damaged Patients• Linked loss of

structure with loss of function

• Phineas Gage = emotional control

• Paul Broca & Carl Wernicke = language centers

o Gunshot wounds, tumors, strokes, Alzheimer’s enable further brain mapping.

Lesioning

• Surgically destroy part of brain & record behavior changes

• Link structure=function

Electrodes = Direct Electrical Stimulation

• Wilder Penfield– Origins of

seizures

– Mapped motor cortex

Electrical Activity

• Monitor and record nervous system (brain) activity

• Electroencephalogram (EEG)

– Electrodes glued to scalp

– Measures brain waves– Regions

Imaging – Observe function• Computerized Axial

Tomography (CAT/CT) Scan

• X-Ray Images of Brain Structures

• Used to determine extent of injuries

Imaging• Magnetic Resonance

Imaging (MRI)

• Radio frequency detects tissue density (O2)

• Detailed structure of brain

• f MRI’s now do function as well

Imaging• Positron Emission

Tomography (PET) Scan

• Inject solution into blood and chart the amount absorbed by brain cells.

• Used to identify function/activity.

http://www.learner.org/resources/series142.htmlProgram 1: Organization and Evolution of Brain Function

BehaviorismScientific Psychology should focus on

observable behavior.

John Watson(1878-1958)

Ivan Pavlov

Psych the Science of Behavior

StimulusStimulusResponseResponse

PsychologyPsychology

Mental Processes cannotbe studied directly

Biological Perspective

FocusHow the body and brain create emotions, memories,and sensory experiences.

FocusHow the body and brain create emotions, memories,and sensory experiences.

Sample Issues• How do evolution and heredity influence behavior?• How are messages transmitted within the body?• How is blood chemistry linked with moods and motives?

Biological Perspective

Focusemotions, memories, and sensory xperiences.

Focusemotions, memories, and sensory xperiences.

Issues• Heredity influence?• Message Transmission?• Blood Chemistry?

Look deep into

Biological basis of behavior

Two sides of things…

• Nerves• Chemicals• Genes• Environmental inputs

• Sensing• Doing• Learning• Memories• Feelings• Decision making

Things to remember…

• Nerves “sense” , “effect” through signal transmission

• Neurotransmitters• Control – Nerves in the brain

– Specific motor and sensory control – Emotional control

• Control – Hormones, Neurotransmitters• Genetic influence• Environmental influence

How do Nerves work?

Windows Mac OS X

Neuron and Neural Impulse

Figure 3.1 Structure of the neuron

Figure 3.2 The neural impulse

Figure 3.3 The synapse

Figure 3.4 Overview of synaptic transmission

Figure 3.19 The cerebral cortex in humans

Figure 3.20 The primary motor cortex

Figure 3.21 Language processing in the brain

The Endocrine System:Glands and Hormones

• Hormones – chemical messengers in the bloodstream– Pulsatile release by endocrine glands– Negative feedback system

• Endocrine glands– Pituitary – “master gland,” growth hormone– Thyroid – metabolic rate– Adrenal – salt and carbohydrate metabolism– Pancreas – sugar metabolism– Gonads – sex hormones

Influence of Heredity & Environment

Nature versus NurtureNature versus Nurture

Genes and Behavior:The Field of Behavioral Genetics

• Behavioral genetics = the study of the influence of genetic factors on behavioral traits

• Chromosomes – strands of DNA carrying genetic information– Human cells contain 46 chromosomes in pairs

(sex-cells – 23 single)– Each chromosome – thousands of genes, also in

pairs• Dominant, recessive• Homozygous, heterozygous• Genotype/Phenotype and Polygenic

Inheritance

Environment?

• Environmental changes

• Learning

• Memories

• Experiences

• Effects of them on biology

• Effect of them on behavior

Assignment

Write….• What is the baby trying to

do?• What will he do on his next

birthday?• Will he change behavior? Or

still do the same?

Explain your answer including the following aspects

• “sensing” nerves

• “Action” nerves (motor nerves)

• Brain’s control of the above

• Memory

• Decision making

• Genes

• Environment / society

Thank You

Inquiries : Dr.Nishan Silva

sunlord_n@hotmail.com

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