How do we receive information from the

world?

In humans and other animals, this is the role of the sensory organs, which

then transmit impulses to the brain via a nerve or nerves.

Five Senses

1.Hearing

2.Sight

3.Smell

4.Taste

5.Touch

How do we receive information from the

world?• These have continued to be regarded as the

classical five senses. Scientists have determined the existence of as many as 15 additional senses: These include sensations of weight, positions of the body, amount of bending of the joints, balance, and bodily needs.

How does each sense work?• Hearing:

The human ear consists of (3)sections:

•The outer ear, the middle ear, and the inner ear.

1) The outer ear includes the auricle, the visible part of the ear that is attached to the side of the head, and the waxy, dirt-trapping auditory canal.

•The tympanic membrane (eardrum) separates the external ear from the middle ear, and air-filled cavity.

•Bridging the cavity between the middle and inner ear, are three small bones- the malleus (hammer), the incus (anvil), and the stapes (stirrup).

•The cochlea and semicircular canals make up the inner ear.

Ear Anatomy  

• Ear drum- a thin membrane that separates the external ear from the middle ear. It transmits sound from the air to the middle ear.

 

• Hammer/Anvil/Stirrup- 3 tiny bones (smallest in the body) amplifies sound from the ear drum to the Cochlea.

• Cochlea- a sensory organ of hearing which is filled with a watery liquid which moves vibrations from middle ear to nerve cells via hair cells.

• Vestibular Nerve – The nerve which transfers information to the brain to be processed.

• Auricle – The external portion of the ear.

Human sensory system

• Is there a difference between hearing and listening?

http://www.youtube.com/watch?v=u3mupIlFIYQ&feature=relmfu (Breakfast club lunch scene)

• What information did you gain? 

• What are the sources for this information?

• What errors could occur from just audio?

Pupil

Eye Anatomy • Iris – The most

forward portion of the eye. Muscles contract the pupil to open and close the eye.

• Pupil – the black center of the Iris which controls the amount of light that enters the eye.

Pupil

• Lens – Refracts light to be focused by the Retina. Changes shape to focus objects at various distances.

• Cornea – Covers the Iris and Pupil. Refracts light to help focus.

• Retina –Receives light and transforms image forming signals through optic nerves to the brain.

• Ciliary Muscle – Changes shape to see distances (near & far).

• Sclera – The white of the eye.

• Optic Nerve – Transfers images to the brain to be processed.

Pupil

Pupil

ScleraRetina

Optic NerveCiliary Muscle

IrisCorneaPupilLens

Sight: The amount of light entering the eye is controlled by the pupil, which dilates and contracts accordingly. The cornea and lens, whose shape is adjusted by the ciliary body, focus the light on the retina, where receptors convert it into nerve signals that pass to the brain.

•A mesh of blood vessels, the choroid, supply the retina with oxygen and sugar.

•Lacrimal glands secrete tears that wash foreign bodies out of eye and keep the cornea from drying out.

•Blinking compresses and releases the lacrimal sac, creating a suction that pulls excess moisture from the eye’s surface.

SMELL

Taste: The tongue is covered with approximately 10,000 taste buds, grouped in areas sensitive to sweet, sour, salty and bitter flavors.

•Chemicals from the food

we eat stimulate

receptors in each of

these areas, and nerves

transmit this input to the

brain.

Touch: In humans, touch is accomplished by nerve endings in the skin that convey sensations to the brain via nerve fibers.

•Nerves end in or between the cells of the epidermis, the outer layer of the skin, in all parts of the body.

•In one complex form of nerve ending, the terminals form tiny swellings, or end bulbs; characteristic of this form are the Pacinian corpuscles found in the sensitive pad of each finger.

•Touch is the least specialized of the senses, but acuteness can be sharpened by use; for example people who are blind exhibit a remarkable delicacy of the tactile sense in their ability to read the fine, raised letters of the Braille System.

•The skin consists of an outer, protective layer (epidermis) and an inner, living layer (dermis) The top layer of the epidermis is composed of dead cells containing keratin, that also makes up hair and nails.

Review of concepts & diagrams

• Psychology Crash Course – Homunculus

• Credits: Hank Green & The Crash Course Channel @ YouTube 2014

What does extra-sensory information (E.S.P.) mean?

• Telepathy is the transfer of thoughts from one person to another.

• Clairvoyance is the ability to recognize objects or events, such as the

contents of a message in a sealed envelope, that are not present to

normal sensory receptors.

• Precognition is unexplained knowledge about future events, such as

knowing when the phone is about to ring.

• Cytokinesis is the ability to move objects by using one’s mental powers

Is E.S.P. Real?

• Experimental support for the existence of E.S.P. is generally weak, and results have not been repeated often.

• Moreover, E.S.P. phenomena such as “reading people’s minds” or bending spoons through mental power cannot be verified by experimental manipulations in the way that other perceptual events can be.

• None of these criticisms means that E.S.P. does not exist this will probably never be proven.

What is the difference between sensation and perception?

• To understand how sensory systems help us create reality, we need basic information about the senses.

• A sense is a system that translates outside information into activity in the nervous system. Messages from the senses are called sensations.

• Perception is the process of using information and your understanding of the world, so that sensations become meaningful experiences. By shaping experience, perceptions influence thoughts, feelings and actions.

• Before something can be perceived, it must be sensed.

How does the body transmit sensory information?

• Fibers extending from the nerve cell body are called axons and dendrites.

• Each neuron generally has only one axon, whose function is to carry signals away from the cell body.

• At the end of each axon are terminal branches with pouch-like sacs called vesicles.

• Dendrites are fibers that receive signals from the axons of other neuronsand carry those signals to the cell body.

- The communication signal between neurons begins with an electrochemical pulse which shoots down the axon.

- The vesicles release a chemical substance called a neurotransmitter.

- The neurotransmitters flow across the gap between the axon and dendrites. - On the dendrite of the next cell the neurotransmitters

reach places where they , chemically fit, or bind, to proteins called receptors

Sensory Information

• All modern brain theories assume that the major brain parts perform different (though overlapping) tasks. This concept, is known as localization of function.

How does the brain process sensory information?

The brain stem: is responsible for functions such as sleeping, waking, dreaming and unconscious bodily functions such as breathing and heart rate.

The cerebellum: contributes to a sense of balance and coordinates the muscles so that movement is smooth and precise. In addition, the cerebellum is involved in remembering certain simple skills and acquired reflexes, analyzing sensory information, solving problems and understanding words.

The thalamus: is the busy traffic officer of the brain. The thalamus relays motor impulses from higher centers to the spinal cord. And conversely, as sensory messages come into the brain, the thalamus directs them to higher centers.

The hypothalamus and the pituitary gland: are involved in drives associated with the survival of both the individual and the species - hunger, thirst, emotion, sex and reproduction. It regulates body temperature and it controls the complex operations of the autonomic nervous system

Pituitary Gland

Frontal LobeOccipital

LobeTemporal Lobe

Parietal Lobe

Frontal Lobe – involved in movement, decision-

making, problem solving, and planning.

Emotions, personality, and motor skills.

Parietal Lobe – sensory information from

different modalities, particularly determining

spatial sense and navigation.

Occipital Lobe – Visual Processing center.

Temporal Lobe – Hearing, language

development and acquisition, and speech.

Review of the brain’s functions

• Crash Course Psychology – Episode # 3 The Chemical Mind

• Crash Course Psychology – Episode #4 Meet Your Master: Getting to Know Your Brain

• *Click the picture to watch the videos