Copgras Delusion

• Copgras Delusion

o Occurs when the amygdala is disconnected from the visual cortex

o People have no emotional response to objects that they see

o Ex. Man who though his parents were imposters

• Does not occur over phone conversations

• Recognition

o Occurs at 114 msec or 10 times/second or 1/10 sec

o It is when a match between perceptual input and a pattern (mental representation) in memory exceeds some criterion and conscious awareness of the pattern occurs

o Rapid and unconscious

o Temporal lobe

• Lower portion of the temporal lobe which extends forward from the visual cortex is the declarative pathway of the visual system

 It compares visual representations with representations of familiar faces and words

• Middle portion of the temporal lobe which surrounds auditory area, organizes features matching auditory input into representations of phonemes

• Logogen Model

o A logogen is a criterion node that determines when the comparison between the input and representation in memory has made a match

o A point where all the representations of a word come

o The more of a perceptual representation that matches, the higher the activation

o When the activation exceeds the criterion for the word represented by the logogen it is perceived and recognized

o Accounts for word recognition

• Frequency effect

o High frequency words have low thresholds

• If you use it a lot you are more conscious of it

o Low frequency words have a higher threshold

o The more that you see it, the better you are at processing it so you do it faster and see them quicker

o Masking studies show evidence

• Words more likely to be reported than non-words, high frequency more that low frequency

• Redundant Pathways

o 3 parallel pathways for recognizing printed words

• Visual whole word pathway activates meaning directly

• Auditory whole word pathway activates sound of word and meaning through auditory pathway

• Letter sequence sounds word out phonetically letter by letter

 Takes longer

 Speed affected by number of letters in word

 Low frequency exception words will produce more mistakes

• Proofreading

o Because we use whole word pathway errors are difficult to detect in high-frequency words and words that preserve the shape

o Homophone errors may be difficult to detect

• Backward mask- mask is last

• Forward mask- mask is first

• Priming

o The presentation of an item which affects the reaction time or probability with which another item is subsequently perceived

o Subliminal

• Activation of a node higher than its resting state but not higher than the threshold so later it will require less subsequent activation and will be easier to process

• Requires a mask

o Visible

• May or may not need masking

• Activated higher than threshold but is lowered

o Repetition

• Each presentation increases the activation until they exceed criterion

o Form priming

• Words activate the words in their neighborhood

o Semantic

• Activation spreads along semantically related logogens

• Neely