1. Unit 4: Sensation and Perception

2. What is a Sense???
A sense is a system that translates information from outside the body into neural activity that can then be perceived by the brain
Sensations are the messages from the senses that make up the raw information sent to the nervous system

3. Flowchart for our Senses:

4. Sense of Hearing The ear is our main sensory organ for hearing
What we sense with our ear are called sound
-A repetitive fluctuation in the pressure of a medium, such as air.
-A sound is determined by its Amplitude, Wavelength, and Frequency

5. Amplitude/Loudness:
Amplitude is the difference between the peak and baseline of a waveform. (in this case sound)\
The higher the Amplitude, the louder the sound will be

6. Wavelength/Frequency:
Wavelength is the distance between one peak to the next in a waveform
The shorter the wavelength, the higher the frequency
Frequency is measured in hertz (Hz)

7. Frequency/Pitch:
Frequency us the number of complete waveforms, or cycles that pass by a given point in space every second
The Higher the frequency, the higher pitch of the sound, the lower the frequency of the sound

8. Timbre: Timbre represents the quality of the sound that we hear
The better the sound quality, the better we can hear and identify the sound

9. Parts of our Sense of Hearing: Pinna
The Pinna (outer ear) is our accessory structure of our sense of hearing
It collects sound from the world around us

10. Parts of our Sense of Hearing: Ear Canal
The Ear Canal directs the sensations deeper into our ear and towards our eardrum (Tympanic Membrane)

11. Parts of our Sense of Hearing: Tympanic Membrane
The Tympanic Membrane (Ear Drum) creates vibrations that match the sound waves matching the waves striking it.

12. Parts of our Sense of Hearing: Cochlea
The spiral shaped, fluid filled part of our ear that transduces what we hear
Transduction: converting physical signals from the environment into encoded neural signals sent to the central nervous system.

13. Place Theory
Place Theory allows us to locate where a sound is coming from without actually seeing the sound being made

14. Light: What We Sense When We See
We can see visible light
Light gives depth and color to all we see
Without light, we cannot see (duh!!!)

15. The Eyes: Accessory Parts
Light enters the eye through the Cornea
This is a convex and semitransparent protective layer of the eye
Its job is to begin to focus the light entering the eye

16. The Eyes: Accessory Parts
As light passes through the pupil, which is right behind the cornea, it becomes more focused
Next, the light passes through the Iris which gives our eyes their color and adjusts the size of the pupil to let in more or less light
The Lens is the last accessory part of the eye

17. The Eyes: Parts of Transduction
The main part of transduction is the retina
This complex organ is tasked with taking the light that has been focused and turned into an image in the back of the eye
To do this, there are many specific structures within the retina

18. In the Retina: Photoreceptors
Photoreceptors are specialized cells in the retina
Within these photoreceptors are photopigments which are sensitive to light
There are two types of photoreceptors
-Cones
-Rods

19. In the Retina: Rods
Rods, called such due to their shape, detect amounts of light
When it is darker, and we cannot discriminate color well, we are using our rods to see

20. In the Retina: Cones
Cones, called such due to their shape, interpret color
Cones are located within the fovea
Depending on the photopigment within the cone, it will pick up one of three colors
-Red, Green, Blue
To interpret other colors, multiple cones must work together

21. Colorblindness
Some people are born with faulty cones and can only see 2 of the 3 colors
We call this colorblindness

22. Sense of Smell and Taste:
Olfaction: The sense of smell
Gustation: The sense of taste
These senses are linked and rely on each other

23. Pheromones:
Chemicals that are released by one animal that are sensed by another animal which affect that animal’s behavior

24. Vemeronasal Organ:
An organ within our olfactory system that is sensitive to pheromones

25. Papillae:
Structures on the tongue that contain taste receptors or taste buds
These help us distinguish what we are eating

26. Sense of Touch Every inch of our skin is covered by touch receptors
Our sense of touch, temperature, pain and kinesthesia are called our somatic senses

27. Gate Control Theory
The theory that a special part (gate) within the spinal cord allows pain to travel to the brain or stops its advance.
To pass the gate, the pain must be strong enough to be registered

28. Analgesia
In rare cases, people can have an absence of pain in a situation where they would normally feel pain
This could be caused by adrenalin or their senses being overloaded.

29. Vestibular Sense: Our 6th Sense
Every inch of our skin is covered by touch receptors
Our sense of touch, temperature, pain and kinesthesia are called our somatic senses

30. Kinesthesia: Every inch of our skin is covered by touch receptors
Our sense of touch, temperature, pain and kinesthesia are called our somatic senses

31. Synesthesia: The Blending of our Senses
In some people, at certain times, our senses can be blended.
Some people can “taste” different colors, or “see” different smells

32. From 2011 AP Exam:
2. Savannah is a junior in high school and is preparing for an exam in her beginning Japanese course. The exam will consist of both written and spoken portions. Although it is her first course in Japanese, Savannah is confident that she will do very well on the exam.
A. Describe how each of the following relates to Savannah’s successful learning and performance.
• Broca’s area
• Use of phonemes
• Modeling
• Chunking
B. Describe how each of the following may hinder Savannah as she prepares for and takes the exam.
• Encoding failure
• Age and language acquisition
C. After the exam, Savannah tells her family and friends that she believes that she spoke fluently and did extremely well on the exam. Describe how each of the following concepts may have influenced her opinion.
• Self-efficacy
• Confirmation bias