Interested in human mental processes, perceptions, optical illusions ? Check the ppt presentation for answers

1. Our nervous system
Mental processes
MSc Miroslava Korenova PhD
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2. Human Mental Processes
The relation of the human mind and the brain have been debated for centuries
 How can immaterial entities may arise from biological material??
 How do we think? How our thoughts look like?
 Do perceptions reflect out most immediate reality? ..or is it only an illusion?
 Why do we have memory?
 How is it possible to understand language?
PERCEPTIONS, THOUGHTS, MEMORIES, ACTIONS, PLANS, UNDERSTANDING JOKES – HOW ALL THESE
ASPECTS OF MENTAL LIFE – DEPEND ONLY ON BRAIN TISSUE FUNCTION??
Think and discuss...
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3. Human Mental Processes
 What are mental processes ??
All activities that arise from out mind – like
perceptions, thoughts, memories, volition
and emotion
Mental processes are sometimes called as
cognitive function
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4. Human Mental Processes
Perception
 Our brain – a highly flexible neural machine – is able to discriminate an
enormous amount of information from the environment
 Therefore a strong filter protecting our brain from overstimulation have
been developed – more than 99% of information is discarded by the
brain as irrelevant and unimportant
 1% of an important sensory information is selected, and than is
channeled to proper motor region of the brain
The continuous stream of information from the receptors is organized
by the brain as perceptions .....
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5. Human Mental Processes
Perception
Perception enables us to identify and
interpret incoming sensory information
in order to understand environment
Our sensory systems are part of nervous
system responsible for processing sensory
information – vision, hearing, touch,
smell, taste and smell
All senses transduct information from
the physical world to the ream of MIND
Without perception we would not be able to identify the colour of a
lavender, the smell of an apple pie, the shape of a pear or murmur of
bees............................
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6. Human Mental Processes
Perception
 Perception is not only a passive receipt of signals
from environment, it is shaped by person´s
memory, experience, expectations and
intelligence
 For long time have been senses considered to
be a passive receptos (only receiving signals
from exterior), however the study of illusions
demonstrated that the brain perceptual system
actively attempts to make sense of their input..
 Our perception is limited to the quality of
processing information (sound volume, light
conditions) and the general specifications of
our perceptual system (e.g. we can hear only at
certain range of frequencies, or our vision is
limited to certain light waves )
Fig.1. The human brain tends to perceive a
complete geometrical shapes, despite their
imcompleteness
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7.  Camouflage – predominantly use of coloration to
make animals hard to see (sleeping owl, buttterfly,
whose drawings on rear wings may birds response
to be eyes of a predator
 Mimicry – when an edible, non poisonous animal
resembles to be an another species (usually
poisonous or non edible)or a part of a natural
object (stick, tree bark, leaf)
Human Mental Processes
Visual Perception
What other examples do
you know???....
The confusing ambiguity of perception
can be exploited in animal world
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8. Human Mental Processes
Perception – optical illusions
 Sensory perception is often the most striking proof of
something factual
 When we perceive something, we
INTERPRET IT AS – REAL
 The assumed link between physical reality and
perception is very strong particularly for the visual
sense (we scrutinize it only when people have bad
vision, or when lighting conditions are not appropriate)
 However our brain is strongly biased by past
experience, memory and expectation
Example on picture:
How many wild cats can you see ??????
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9. Human Mental Processes
figure-ground perception – optical illusion
Rubin vase: Vase or two faces?? Your perception decides
what you see first , neither answer is wrong, it is simply a
difference of perspective, or point of view – called
personal perspective
Kanizsa's Triangle: One triangle or two triangles?
These spatially separate fragments give the impression
of a (black) triangle, defined by a sharp illusory contour
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10. Human Mental Processes
visual perception – optional slide
A Max Velmans model in visual perception:
1. Light rays from a cat impinge on the Subject’s
eye
2. Impulses travel up via the optic nerve producing
a neural representation of the cat within S’s
central nervous system (CNS)
3. CNS activity, in turn, has a causal influence on
S’s mind, resulting in a percept of a cat
4. The percept (of a cat) in the mind of S is quite
separate both from the neural representation
(of a cat) in S’s brain and the cat (as-perceived
by external observer) out-there in the world
WE DON'T SEE THINGS AS THEY ARE, WE
SEE THINGS AS WE ARE
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11. Human Mental Processes
Thoughts
 Thinking is a mental process that results
in formation of thoughts
 A thought may be an idea, image, sound
or emotional feeling
 Thinking is a manipulation with
information :
we form concepts
solve the problem
we make decisions
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I can do this...

12. Human Mental Processes
Memories
 Imagine a situation, that you do not know your name, or where you
live. Probably you do no know faces of your parents or friends. You
do not remember what you did yesterday, or what are you going to
do tomorrow, you do not even know what happened a minute ago.
You are trying to declare what you had for a breakfast or how did
you get to school this morning, .....or even why .....
..welcome to the world where memory takes
no place...........
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13. Human Mental Processes
Memories
Memory is essential to our lives, without memory we will be lost in time
and place. We will not be able to think about past events, operate in the
present and organize plans for the future....proper memory functioning is
a key aspect of our intelligence
The term memory involves three main stages of information processing:
Encoding – when an information comes to our memory system – usually via
our sensory organs – eyes, ears... (we see, hear or read something what is
going to be remembered..)
Storage – involves the nature of memory storage – how long it will last and
what kind of information will be held...
Retrieval – getting information out of storage
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14. Human Mental Processes
Memories – physiological view
 Memories are - changes in synaptic
transmission from one neuron to the next
 These changes result in formation of new
pathways of signals through the neural
circuits of the brain called - memory
traces
 Memory traces can be activated
(reactivated) by the thinking process to
reproduce memories
 Some memories last for seconds, minutes,
hours, some for days, months or for a
lifetime......................
Can you name all parts of a synapse?
Describe a simplified model of synaptic
transmission.....
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15. Human Mental Processes
short-term memory
 Lasts for seconds (15-30s)
 Has limited capacity
 Rule 7±2 items can be stored
 Chunking of information can increase storage capacity
 Encoding is primarily acoustic
Example:
Try to remember as many numbers as you can:
- Read the pairs of numbers aloud, leaving a short pause between each pair
25 34 78 28 42 97 5 – show in pairs, 1sec intervals
- After reading that, please, show the next slide with pink elephant
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16. And now, try to rehearse the same
numbers again..
How many of them can you remember?
What has happened to the short-term
memory?
What happens when you cannot use
maintenance rehearsal?
.............Memory decays very quickly
Show the pink
elephant for a 10
seconds.....than
remove it and show
the text below
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17. Human Mental Processes
long -term memory
 Intermediate long-term memory – lasts for days,
months, however when not necessary all information
is lost
 Long-term memory – once stored, can be recalled
up to years or even a lifetime later, is provided by
structural changes on synapses
Divided on subcategories :
 Episodic memory – codes storing of information about
past events – episodes of our life (1st day at school, 1st
kiss)
 Semantic memory – holds general knowledge about
world, learned facts (capital city of France is Paris)
 Procedural memory – codes how to do things – how
to ride a bike, drive a car, play piano, make a coffee..
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18. Human Mental Processes
Memory consolidation
 Short-term memory is converted into long-term memory in process called
consolidation
 There must initiate chemical, physical, anatomical changes in structure
of synapses that are responsible for type of information (to be
processed)
 Process requires 5-10min for minimal consolidation, 1 hour or more for
better consolidation
Note:
The more emotionally charged event/situation or experience – the better it
is remembered – means better consolidation
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19. Human Mental Processes
Memory rehearsal
 Rehearsal of the same information
again and again in the mind
potentiates the degree of transfer
from short-term memory into log-
term memory
 The key brain structure responsible
for transfer of information from
short-term memory into long-term
memory is
HIPPOCAMPUS
Do we have this hippocampus in our
brains??
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20. Human Mental Processes
Role of hippocampus in memory consolidation
 Hippocampus is located in the medial temporal lobe of
the brain, each hemisphere has its „own“ hippocampus (pl .
hippocampi)
 The term – hippocampus – was derived after its resemblance
to a seahorse (greek hippos – meaning „seahorse“ and
campos – „sea monster“ due to its similar shape
 The hippocampus forms a part of a limbic system of the
brain – an area responsible for managing emotions
 It has a key function in memory – mainly transfer of
information (consolidation) from short term memory into
long term memory. Without hippocampus a person is not
able to remember recent information, however almost all
previously learned information remain intact
 It has been shown that has also a critical role in visuospatial
orientation (it serves as a brain map)
Figure representing hippocampus location in
human brain
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21. Human Mental Processes
Conclusions
 All activities that arise from out mind –perceptions, thoughts, memories, volition and emotions are called
cognitive processes
 Perception enables us to identify and interpret incoming sensory information in order to understand
environment
 Our sensory systems are part of nervous system responsible for processing sensory information – vision, hearing,
touch, smell, taste and smell
 Perception is not only a passive receipt of signals from environment, it is shaped by person´s memory,
experience, expectations and intelligence
 The confusing ambiguity of perception can be exploited in animal world - examples – camouflage, mimicry
 Thinking is a mental process that results in formation of thoughts, a thought may be an idea, image, sound or
emotional feeling
 Memory is essential to our lives,..proper memory functioning is a key aspect of our intelligence
 Some memories last for seconds, minutes, hours, some for days, months or for a lifetime
 Long-term memor can be divided into subcategories according to type of information stored – episodic,
semantic, procedural
 Consolidation – is a process of conversion of information from short-term memory to long-term memory,
the key brain structure is hippocampus
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22. Human Mental Processes
Refences
 Hall, John E.Guyton, Arthur C. (2011) Guyton and Hall textbook of medical physiology /Philadelphia, PA : Saunders/Elsevier,.
 Kandel, E. R., Schwartz, J. H. 1., & Jessell, T. M. (2000). Principles of neural science(4th ed.). New York: McGraw-Hill, Health Professions
Division.
 McLeod, S. A. (2009). Short Term Memory. Retrieved from www.simplypsychology.org/short-term-memory.html
 McLeod, S. A. (2010). long-term Memory. Retrieved from www.simplypsychology.org/long-term-memory.html
 https://en.wikipedia.org/wiki/Hippocampus
 http://www.telegraph.co.uk/news/newstopics/howaboutthat/3520448/Optical-Illusions-the-top-20.html
 CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=454111
 https://en.wikipedia.org/wiki/Haptic_perception
 https://en.wikipedia.org/wiki/Z%C3%B6llner_illusion
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