Cognitive neuroscience
Part 2
Chapters 8 to 14 of book Purves et al., Principles of Cognitive
Neuroscience, 2nd edition
ISBN 978-0-87893-573-4
Combination of book and lectures
Chapter 8: Memory: varieties and mechanisms................................................2
Chapter 9 & lecture 8: Declarative memory.....................................................9
Chapter 10 & lecture 9: Emotion...................................................................12
Chapter 11: Social cognition.........................................................................18
Chapter 12 & lecture 11: Language...............................................................20
Chapter 13 & lecture 12: Executive functions.................................................24
Chapter 14 & lecture 13: Decision making.....................................................28
,Chapter 8: Memory: varieties and mechanisms
Memory allows us to learn from the past, understand the present and plan for the future.
all cognitive abilities depend on memory
Memory is not a unitary phenomenon
- Working memory = system that maintains memories for a few seconds or minutes
- Systems that maintain memories for longer periods
o Declarative memory: conscious memories for events and facts
o Nondeclarative memory: task performance
Memory = the series of processes whereby the nervous system acquires information from
new experiences, retains this information over time, and eventually uses it to guide behavior
and plan future actions. Consists of three phases
- Encoding = the processes whereby experiences can alter the nervous system
memory traces are believed to involve primarily changes in the strength and/or
number of synaptic connections between neurons
- Storage = the retention of memory traces over time long term retention requires
cell- and system-level stabilization or consolidation processes (chapter 9)
- Retrieval = the accessing of stored memory traces, which may lead to a change in
behavior and sometimes is associated with the conscious experience of remembering
Learning = used as a synonym of encoding and can also describe gradual changes in
behavior as a function of training
refers to the combined effect of encoding, storage and retrieval phases in gradually
enhancing the performance of a particular task.
Delayed non-match-to-sample task = to measure declarative memory in non-human animals
- Sample phase: monkey is shown a stimulus above a food reward
- Delay phase: monkey can no longer see the stimulus and reward
- Choice phase: monkey is presented with the previously rewarded stimulus along with
a new stimulus that conceals the food reward. The animal must select the new stimulus
in order to obtain the reward
showed that lesions of the medial temporal lobe severely impair memory in monkeys
Memory systems = groups of memory processes, associated with brain regions that tend to
interact to mediate performance over a class of similar memory tasks.
Most tasks are sensitive to the contributions of more than one memory system
Short-term memory (seconds or minutes) involves different mechanisms than long-term
memory (hours, days, or weeks)
Working memory = the maintenance and manipulation of information online for a few
seconds or minutes
Long-term memory
Declarative memory / explicit memory = conscious memory for events (episodic memory)
and facts (semantic memory)
Nondeclarative memory / implicit memory = memories that are expressed through
performance independently of consciousness, also several different forms.
,
, Working memory versus declarative memory
Amnesia = severe memory loss most telling evidence supporting the distinction between
working memory and declarative memory
- Childhood amnesia = the inability to remember events that took place during the first
years of life.
- Psychogenic amnesia = memory loss due to psychological trauma
- Anterograde amnesia = memory loss affecting information acquired after brain
damage. Loss of the ability to form new memories for events
- Retrograde amnesia = memory loss affecting information before the lesion
Amnesia due to brain lesions most often arises from bilateral damage to the medial temporal
lobe. Unilateral damage usually produces relatively mild memory deficits, the spared lobe
regions still support some aspects of memory.
Single dissociation = patients who suffer from impaired declarative memory but not working
memory.
Double dissociation = brain-damaged patients who are impaired in working memory but not
in declarative memory. Lesions are typically in the left temporoparietal cortex
Declarative versus nondeclarative memory
Occipital lobe damage may impair nondeclarative memory, tested with visual priming.
Nondeclarative memory
All forms are expresses through performance and are independent of conscious awareness.
Evidenced by changed behavior, even if the person in unaware that memories from past
experience are being accessed.
- Priming = a change in the efficacy of stimulus processing due to a previous encounter
with the same or a related stimulus, in the absence of conscious awareness about the
first encounter
Depending on the relationship between the stimulus that generates the priming effect (prime)
and the stimulus eliciting that effect (target), priming can be classifies as direct or indirect.
Direct priming = prime and target are the same: repetition priming.
o Perceptual priming = the test cue and target are perceptually related
o Conceptual priming = cue and target are semantically of associatively related.
Indirect priming = prime and target are different
o Semantic priming = prime and target are related (like envelope and letter)
Perceptual priming depends on brain systems different from those underlying declarative
memory and episodic memory. Perceptual priming depends on sensory regions of the cortex,
such as the visual regions of the occipital lobe.
Best when perceptual stimuli stay the same in encoding and retrieval phases.
reduced when shift in symbols (from pictures to words)
reduced when changes in modality (auditory to visual presentation)
The greater the perceptual change, the greater the attenuation (failure) of perceptual priming
Levels of processing = the way of processing, semantic vs. perceptual. The reason why you
think about the information you’re reading instead of the font it’s written in.
perceptual priming is not affected by the levels of processing manipulations
double dissociation between perceptual priming and episodic memory: these two forms
depend on different brain systems.
Part 2
Chapters 8 to 14 of book Purves et al., Principles of Cognitive
Neuroscience, 2nd edition
ISBN 978-0-87893-573-4
Combination of book and lectures
Chapter 8: Memory: varieties and mechanisms................................................2
Chapter 9 & lecture 8: Declarative memory.....................................................9
Chapter 10 & lecture 9: Emotion...................................................................12
Chapter 11: Social cognition.........................................................................18
Chapter 12 & lecture 11: Language...............................................................20
Chapter 13 & lecture 12: Executive functions.................................................24
Chapter 14 & lecture 13: Decision making.....................................................28
,Chapter 8: Memory: varieties and mechanisms
Memory allows us to learn from the past, understand the present and plan for the future.
all cognitive abilities depend on memory
Memory is not a unitary phenomenon
- Working memory = system that maintains memories for a few seconds or minutes
- Systems that maintain memories for longer periods
o Declarative memory: conscious memories for events and facts
o Nondeclarative memory: task performance
Memory = the series of processes whereby the nervous system acquires information from
new experiences, retains this information over time, and eventually uses it to guide behavior
and plan future actions. Consists of three phases
- Encoding = the processes whereby experiences can alter the nervous system
memory traces are believed to involve primarily changes in the strength and/or
number of synaptic connections between neurons
- Storage = the retention of memory traces over time long term retention requires
cell- and system-level stabilization or consolidation processes (chapter 9)
- Retrieval = the accessing of stored memory traces, which may lead to a change in
behavior and sometimes is associated with the conscious experience of remembering
Learning = used as a synonym of encoding and can also describe gradual changes in
behavior as a function of training
refers to the combined effect of encoding, storage and retrieval phases in gradually
enhancing the performance of a particular task.
Delayed non-match-to-sample task = to measure declarative memory in non-human animals
- Sample phase: monkey is shown a stimulus above a food reward
- Delay phase: monkey can no longer see the stimulus and reward
- Choice phase: monkey is presented with the previously rewarded stimulus along with
a new stimulus that conceals the food reward. The animal must select the new stimulus
in order to obtain the reward
showed that lesions of the medial temporal lobe severely impair memory in monkeys
Memory systems = groups of memory processes, associated with brain regions that tend to
interact to mediate performance over a class of similar memory tasks.
Most tasks are sensitive to the contributions of more than one memory system
Short-term memory (seconds or minutes) involves different mechanisms than long-term
memory (hours, days, or weeks)
Working memory = the maintenance and manipulation of information online for a few
seconds or minutes
Long-term memory
Declarative memory / explicit memory = conscious memory for events (episodic memory)
and facts (semantic memory)
Nondeclarative memory / implicit memory = memories that are expressed through
performance independently of consciousness, also several different forms.
,
, Working memory versus declarative memory
Amnesia = severe memory loss most telling evidence supporting the distinction between
working memory and declarative memory
- Childhood amnesia = the inability to remember events that took place during the first
years of life.
- Psychogenic amnesia = memory loss due to psychological trauma
- Anterograde amnesia = memory loss affecting information acquired after brain
damage. Loss of the ability to form new memories for events
- Retrograde amnesia = memory loss affecting information before the lesion
Amnesia due to brain lesions most often arises from bilateral damage to the medial temporal
lobe. Unilateral damage usually produces relatively mild memory deficits, the spared lobe
regions still support some aspects of memory.
Single dissociation = patients who suffer from impaired declarative memory but not working
memory.
Double dissociation = brain-damaged patients who are impaired in working memory but not
in declarative memory. Lesions are typically in the left temporoparietal cortex
Declarative versus nondeclarative memory
Occipital lobe damage may impair nondeclarative memory, tested with visual priming.
Nondeclarative memory
All forms are expresses through performance and are independent of conscious awareness.
Evidenced by changed behavior, even if the person in unaware that memories from past
experience are being accessed.
- Priming = a change in the efficacy of stimulus processing due to a previous encounter
with the same or a related stimulus, in the absence of conscious awareness about the
first encounter
Depending on the relationship between the stimulus that generates the priming effect (prime)
and the stimulus eliciting that effect (target), priming can be classifies as direct or indirect.
Direct priming = prime and target are the same: repetition priming.
o Perceptual priming = the test cue and target are perceptually related
o Conceptual priming = cue and target are semantically of associatively related.
Indirect priming = prime and target are different
o Semantic priming = prime and target are related (like envelope and letter)
Perceptual priming depends on brain systems different from those underlying declarative
memory and episodic memory. Perceptual priming depends on sensory regions of the cortex,
such as the visual regions of the occipital lobe.
Best when perceptual stimuli stay the same in encoding and retrieval phases.
reduced when shift in symbols (from pictures to words)
reduced when changes in modality (auditory to visual presentation)
The greater the perceptual change, the greater the attenuation (failure) of perceptual priming
Levels of processing = the way of processing, semantic vs. perceptual. The reason why you
think about the information you’re reading instead of the font it’s written in.
perceptual priming is not affected by the levels of processing manipulations
double dissociation between perceptual priming and episodic memory: these two forms
depend on different brain systems.
