Textbook Notes (280,000)
CA (170,000)
UTSC (20,000)
Psychology (10,000)
PSYB57H3 (300)
Chapter 2

PSYB57H3 Chapter Notes - Chapter 2: Temporal Lobe, Amygdala, Edge Detection


Department
Psychology
Course Code
PSYB57H3
Professor
George Cree
Chapter
2

This preview shows pages 1-3. to view the full 11 pages of the document.
Chapter Two: Neural Basis for Cognition
Using variety of methods and many piece of evidence is crucial part for inference to best
explanation ( is the methodological core of our field)
Each part of brain has its own specialized function behaviour, thoughts, and feelings almost
invariably depend co-ordinated action of many brain regions
The Capgras Syndrome: An initial Example
damage anywhere in brain will produce specific and sometimes highly disruptive symptoms
Capgras syndrome it’s a rare disorder on its own but can accompany Alzhiemier’s
syndrome and sometimes in elderly the disorder can result from various injuries to brain
People w/ this syndrome are able to recognize the people in their world (e.g. husband) but is
convinced that these people are not who they appear to be (e.g. real husband has been
kidnapped they believe this)
Say there is slight diff b/w impostor and real person (subtle changes in personality or
appearance) but others can’t notice this this add to their bewilderment
Feelings worsen w/ developing all sorts of paranoid suspicions some instance they take
desperate steps e.g. murdering the supposed impostor
Researcher think the problem lies in the fact that facial recognition involve 2 separate systems in
the brain one is cognitive appraisal & other is more global and somewhat emotional
appraisal concordance of these 2 appraisal leads to certainty of recognition
In capgras syndrome the emotional processing is disturbed have intellectual identification
w/out the famility response e.g. you look like my father & and trigger warmth in me in
here you look like my father but no familiarity so must be someone else
Neural Basis for Capgras Syndrome
Neuroimaging techniques produce high quality, 3d pic of living brain w/out disturbing brain
owners
PET scan suggest link b/w Capgras syndrome & abnormalities in several brain areas one
damage is in the temporal lobe esp. in right side of head
Probably disrupts amygdala which serve as emotional evaluator helps to detect stimuli
associated w/ threat or danger & for detecting positive rewards
o essential for making judgment of looking familiar to triggering of warm feeling
2nd half of two-system hypothesis patients w/ this syndrome also have brain abnormalities in
frontal lobe esp. right prefrontal cortex
fMRI scan of schizophrenia show diminished frontal lobes activity when experiencing
hallucinations
this relevant is that w/ damage frontal lobe in Capgras patients are less able to keep track of
what is real & what is not what is plausible and what is not as result, weird beliefs can
emerge unchecked including delusions

Only pages 1-3 are available for preview. Some parts have been intentionally blurred.

What Do We Learn From Capgras Syndrome?
Evidence suggest that recognition has two separate parts 1) hinges on factual knowledge & 2)
more “emotional” and tied to the warm sense of familiarity
Amygdala disruption explain why there is no sense of familiarity w/ people & prefrontal damage
explain the crazy hypothesis Capgras patients come w/ to explain their skewed perception
can use Capgras syndrome (and other biological evidence) to illuminate broader issues about
the nature of the brain and of the mind.
Other biological evidence also suggests amygdala plays a central part in helping people
remember the emotional events of their lives
other evidence indicates that the amygdala plays a role in decision-making especially for
decisions that rest on emotional evaluations of one’s options emotional evaluator
Capgras syndrome show that the emotional evaluator works in a fashion separate from our
evaluation of factual information
o There are occasions in which someone’s evaluation of the facts points toward one
conclusion, while an emotional evaluation points toward a different conclusion
It also tell us useful stuff about intact brain functions e.g. In order to recognize your father -
one part of brain have to have factual memory of your father & another to analyze visual input
as you look at your father another to match input to memory of our father another for
emotional evaluation of the input
o A different site assembles the data from all these other sites, and so registers the fact
that the face being inspected does match the factual recollection of your father’s face
and also produces a warm sense of familiarity.
o if the coordination among these areas is disruptedyet another area works to make
sure you offer plausible hypotheses about this, and not zany ones.
The Principal Structures of the Brain
brain weighs b/w 3-4 pound but have roughly trillion neurons & 10 billion connections
diff part of brain perform diff jobs clinical evidence - symptoms produced by brain depend
heavily
o e.g. 1848 Phineas Gage to suffer damage in the front-most part of his brain this
damage led to severe personality and emotional problems
o e.g. 1861 Paul Broca noted that damage in a different location, on the left side of the
brain, led to a disruption of language skills.
o 1911 - Édouard Claparède reported his observations with patients who suffered
from profound memory loss, a loss produced by damage in still another part of the
brain.
Hindbrain, Midbrain, Forebrain
brain is divided into three main structures: the hindbrain, the midbrain, and the forebrain
Hindbrain
sits directly atop the spinal cord and includes several structures crucial for controlling key life

Only pages 1-3 are available for preview. Some parts have been intentionally blurred.

functions e.g. the rhythm of heartbeats and the rhythm of breathing are controlled
help maintaining the body’s overall tone helps maintain the body’s posture and balance, and
it helps regulate the brain’s level of alertness.
largest area in it is cerebellum - main role is the coordination of our bodily movements and
balance
o Recent studies suggest it play other roles & damage to it can cause problems in spatial
reasoning, discriminating sounds & integrating inputs from various sensory systems
Midbrain
plays an important part in coordinating our movements, including the skilled, precise movements
of the eyes
relay auditory information from the ears to the areas in the forebrain where this information is
processed and interpreted
other structures in the midbrain help to regulate our experience of pain
Human’s largest region) Forebrain
this structure surrounds (and hides from view) the other parts of brain e.g. hind or midbrain
Only the outer surface of the forebrain that is visible in pictures this is the cortex
cortex is just a thin covering on the outer surface of the brain about 3 mm thick & but is 80%
of human brain due to its convoluting structure ( wrinkles) which is brain most obvious visual
feature
some of the valleys b/w wrinkles are deep grooves that anatomically divide the brain into diff
sections deepest grove is longitudinal fissure it goes from front to back of brain separating
the left and right cerebral hemisphere
other fissures divide cortex in each hemisphere into 4 lobes & named after bones that cover
them(skull)
frontal lobe (in front of brain & behind forehead) is divided from parietal lobe by central fissures
at brain’s top most part
bottom edge of frontal lobe is marked by lateral fissure & below it is the temporal lobe
at the very back of brain connected to parietal & temporal is the occipital lobe
Subcortical Structures
underneath cortex are subcortical parts of the forebrain
Thalamus brain region that acts as relay station for nearly all sensory info going to the cortex
Underneath thalamus hypothalamus play crucial role in the control of motivated
behaviours (e.g. eating, sexual activity)
Surrounding thalamus & hypothalamus is another set of interconnected structures that
together form the limbic system
o Included here is amygdala , hippocampus both are underneath the temporal lobe
they are essential for learning & memory & emotional processing
You're Reading a Preview

Unlock to view full version