Week 1: intro
Assumptions
- Neural acitivty underlies behavior
- Cognitive functions can be localized in the brain
- Mental representations are stable over time
- The system (brain) is stable over time
Mind-body
- If neural acitivty underlies behavior, how can mind and body relate?
- Dualism: mind and body are separate
- Monism: mind and body are linked
Perspetives on linking mind and body
- Parallelism: mind and brain and two aspects of the same reality. There is a 1-1
correspondence between reality and brains states.
- Epiphenomenalism: the mind is a by-product of the brain; mental states are caused by
physical states. Mental states do not influence physical states.
- Isomorphism: cognition and the brain share a pattern rather than being connected in 1-
1 correspondence
o Mental representation: brain representation of external world
- Emergent interactionalism: cognition are emergent properties of the brain, which both
exist on their own and modify the underlying functional organization of the brain.
- Mental events are functional derivatives from the brain circuits and their connections.
They are emergent.
- Roger Sperry: studies of split brain patients.
Modularity
- Enough specilizaion in the system to allow for modulairyt and functional specification
(parts of the brain uniquely engaged in mediating certain function.
Forward vs reverse inference
- Forward inference is that you put them in a task and you see certain brain areas light up.
So you conclude that oh yes this brain area is for this task
- Reverse inference is when you see brain activity, you think oh I think theyre doing face
detection
o Default mode network. Scanner do nothing and we know the mode.
o Brain fingerprinting: decide to see if a person is guilty or innocent based on EEG
form. Used in steven avery (making a murder) case
Statistical power
- Probability of a test to detect the effect if it exists.
- Generally, probability of about 80% is considered sufficient
, - If we test more participants, does it make hypotheses stets more likely to detect the
effect?
Statistical power refers to the ability of a study to detect an effect when it is present. In single
patient testing, statistical power is especially important because these studies typically involve
a small sample size, often just one individual, making it difficult to detect effects that may be
present.
Week 2: methods
Definitions:
- Cognitive neuroscience: a field of study that seeks to uncover the links between
cognitions and the brain using interdisplinary methodologies
- Fuelled in early 1990s by the rise of neuroimaging methods that allowed for imaging of
LIVE human brain in action
- Two key principles of cognitive neuroscience:
o Cognitions arise from the brain.
o Applications of interdisplianry investigations
Neuropsychology:
- A field of study that is concerned with understanding the structure and the function of
the brain and how they relate to cognitions and behavior.
- It is also concerned with understanding and describing neurological conditions, as well
as developing diagnostic, assessments, and rehabilitation methods.
- Neuropsychology is a broad term and includes not only single case patient studies, but it
also applies in lesion studies in human and animals, and recording of brain activity from
various parts of the brain.
Methods
- Neuroanatomy
o Post-mortem analysis of the nervous system
o Gross neuroanatomy (general structural divide)
o Fine neuroanatomy (cell structure and connections)
- Neurophysiology
o In vivo technique for manipulating and measuring neuronal activity
o Microelectrodes and macroelectrodes
o Stimulating/measuring
- Lesion studies
o How removal or alteration of particular brain structure changes/affects resulting
behavioral/cognitions
o Human and animal, irreversible and reversible
o Human: result of brain injury are rare cases specialized surgery (H.M)
Irreversible lesions: vascular disorders (Stroke, hypoxia, aneurysms)
Tumors (mass impeding pushing on brain)
, Degenerative disorder (Alzheimer’s parkinsons)
Head trauma (open, closed, TBI)
o Caramazza and McCloskey
Analysis of impaired performance after brain damage contributes to our
understanding of the typical functional organization of the brain.
One reason for this is because its brain damage to areas usually do not
result in undifferentiated but rather circumscribed (strict) loss of
function. Thinks 1-1 correlation with brain and behavior.
o Single vs double dissociation logical methods
Single dissociation, I test Y and I test for damage in specific input,
something is lost.
Double dissociation, I have two people, they each have a damaged part
and they do test and find its different deficiencies.
o Human reversible lesions:
TMS (Transcraanial magnetic simulation)
tDCS (Transcranial direct-current stimulation)
o neuroimaging
fMRI: excellent spatial resolution, poor temporal resolution. Anatomical
and functional changes, connectivity analysis
EEG: poor spatial resolution, excellent temporal resolution. Voltage and
frequency of neuronal firing.
o Behavioral tests
Critical component of brain-behavioral links
Elicit and measure behaviors.
Chronometric investigation (response time, accuracy)
Eye tracking investigations (movement and position) attention,
implicit behavior, info processing, visual perception
Paper and pencil test (neuropsychological tools) relies on
interpretation.
Subjective reports -> becoming more popular.
o How do behavioral tests inform neuroimaging and psychological investigations?
How they necessary?
Single patient studies
- CaraMazza and mcClosey
o We can use the pattern of impaired performance observed in neuropsychological
patients to infer the structure and function of a normal cognitive system
o Why? Because both impaired and typical cognitive function results from the
same underlying brain function
o Furthermore, brain damage does not result in an undifferentiated loss of
function but a selective loss of a particular ability.
How to make this link?
o Power: how many suggests find the likelihood
, Power analysis: bigger effects don’t need that many participants, smaller
effect needs more participants.
- Must use single patient only and as a result avoid clumping patients into disorder
categories
o Look for commonality, take individual and imply group function. Lesion is not
under experiment control, usually we average the data but then we’re clumping.
Look at differences rather than commonalities.
- Fractionality: selective brain damage results in a selective not undifferentiated loss of
ability
- Modularity: complex function is represented in terms of more basic components of
processing.
- Transparency: pathological performance will provide a basis for interfering which
module is affected
- Universality: the model is true of normal human brain in general
-
Week 3: Phantom Limb
plasticity: changes in typical neural organisation (Synapses, pathways) as a function of
behavior, environment, injury
- Umbrella term that covers multitude of phenomena and changes (normal development,
long and short term changes in brain organization, brain chemistry)
- Includes both functional and structural changes occurring in the brain as result of
reorganization.
- may (2011) defines neuroplasticity as the environmentally driven constant
rearrangement of network homeostasis balancing the integration of neuronal activity,
neurotransmitter release, neuronal (perhaps glial) morphogenesis and changes in
network formation including formation and elimination of synaptic structures.
example:
- typical development: the brain rapidly reorganizes itself in the first few years of life
- expertise: musicians, evidence that the brain dedicates more space to those fingers that
play the instrument
- injury: loss of vision, evidence indicating that the brain may rededicate visual processing
areas to other sensory modalities (tactile)
o evidence of plasticity in sensory, motor, and occipital cortex in blind participatns
learning braille
after learning braille, the visual cortex becomes switched
- TMS can be used to examine the effects of visual and somatosensory cortex disruptions
of braille reading in blind indivudals to study the time course of information processing
o rTMS applied over the visual cortical area disrupts braille reading in blind
persons
o it can also induce tactile sensations in finger of braille readers
if inhibit sensorimotor cortex, cannot even detect so cant read
Assumptions
- Neural acitivty underlies behavior
- Cognitive functions can be localized in the brain
- Mental representations are stable over time
- The system (brain) is stable over time
Mind-body
- If neural acitivty underlies behavior, how can mind and body relate?
- Dualism: mind and body are separate
- Monism: mind and body are linked
Perspetives on linking mind and body
- Parallelism: mind and brain and two aspects of the same reality. There is a 1-1
correspondence between reality and brains states.
- Epiphenomenalism: the mind is a by-product of the brain; mental states are caused by
physical states. Mental states do not influence physical states.
- Isomorphism: cognition and the brain share a pattern rather than being connected in 1-
1 correspondence
o Mental representation: brain representation of external world
- Emergent interactionalism: cognition are emergent properties of the brain, which both
exist on their own and modify the underlying functional organization of the brain.
- Mental events are functional derivatives from the brain circuits and their connections.
They are emergent.
- Roger Sperry: studies of split brain patients.
Modularity
- Enough specilizaion in the system to allow for modulairyt and functional specification
(parts of the brain uniquely engaged in mediating certain function.
Forward vs reverse inference
- Forward inference is that you put them in a task and you see certain brain areas light up.
So you conclude that oh yes this brain area is for this task
- Reverse inference is when you see brain activity, you think oh I think theyre doing face
detection
o Default mode network. Scanner do nothing and we know the mode.
o Brain fingerprinting: decide to see if a person is guilty or innocent based on EEG
form. Used in steven avery (making a murder) case
Statistical power
- Probability of a test to detect the effect if it exists.
- Generally, probability of about 80% is considered sufficient
, - If we test more participants, does it make hypotheses stets more likely to detect the
effect?
Statistical power refers to the ability of a study to detect an effect when it is present. In single
patient testing, statistical power is especially important because these studies typically involve
a small sample size, often just one individual, making it difficult to detect effects that may be
present.
Week 2: methods
Definitions:
- Cognitive neuroscience: a field of study that seeks to uncover the links between
cognitions and the brain using interdisplinary methodologies
- Fuelled in early 1990s by the rise of neuroimaging methods that allowed for imaging of
LIVE human brain in action
- Two key principles of cognitive neuroscience:
o Cognitions arise from the brain.
o Applications of interdisplianry investigations
Neuropsychology:
- A field of study that is concerned with understanding the structure and the function of
the brain and how they relate to cognitions and behavior.
- It is also concerned with understanding and describing neurological conditions, as well
as developing diagnostic, assessments, and rehabilitation methods.
- Neuropsychology is a broad term and includes not only single case patient studies, but it
also applies in lesion studies in human and animals, and recording of brain activity from
various parts of the brain.
Methods
- Neuroanatomy
o Post-mortem analysis of the nervous system
o Gross neuroanatomy (general structural divide)
o Fine neuroanatomy (cell structure and connections)
- Neurophysiology
o In vivo technique for manipulating and measuring neuronal activity
o Microelectrodes and macroelectrodes
o Stimulating/measuring
- Lesion studies
o How removal or alteration of particular brain structure changes/affects resulting
behavioral/cognitions
o Human and animal, irreversible and reversible
o Human: result of brain injury are rare cases specialized surgery (H.M)
Irreversible lesions: vascular disorders (Stroke, hypoxia, aneurysms)
Tumors (mass impeding pushing on brain)
, Degenerative disorder (Alzheimer’s parkinsons)
Head trauma (open, closed, TBI)
o Caramazza and McCloskey
Analysis of impaired performance after brain damage contributes to our
understanding of the typical functional organization of the brain.
One reason for this is because its brain damage to areas usually do not
result in undifferentiated but rather circumscribed (strict) loss of
function. Thinks 1-1 correlation with brain and behavior.
o Single vs double dissociation logical methods
Single dissociation, I test Y and I test for damage in specific input,
something is lost.
Double dissociation, I have two people, they each have a damaged part
and they do test and find its different deficiencies.
o Human reversible lesions:
TMS (Transcraanial magnetic simulation)
tDCS (Transcranial direct-current stimulation)
o neuroimaging
fMRI: excellent spatial resolution, poor temporal resolution. Anatomical
and functional changes, connectivity analysis
EEG: poor spatial resolution, excellent temporal resolution. Voltage and
frequency of neuronal firing.
o Behavioral tests
Critical component of brain-behavioral links
Elicit and measure behaviors.
Chronometric investigation (response time, accuracy)
Eye tracking investigations (movement and position) attention,
implicit behavior, info processing, visual perception
Paper and pencil test (neuropsychological tools) relies on
interpretation.
Subjective reports -> becoming more popular.
o How do behavioral tests inform neuroimaging and psychological investigations?
How they necessary?
Single patient studies
- CaraMazza and mcClosey
o We can use the pattern of impaired performance observed in neuropsychological
patients to infer the structure and function of a normal cognitive system
o Why? Because both impaired and typical cognitive function results from the
same underlying brain function
o Furthermore, brain damage does not result in an undifferentiated loss of
function but a selective loss of a particular ability.
How to make this link?
o Power: how many suggests find the likelihood
, Power analysis: bigger effects don’t need that many participants, smaller
effect needs more participants.
- Must use single patient only and as a result avoid clumping patients into disorder
categories
o Look for commonality, take individual and imply group function. Lesion is not
under experiment control, usually we average the data but then we’re clumping.
Look at differences rather than commonalities.
- Fractionality: selective brain damage results in a selective not undifferentiated loss of
ability
- Modularity: complex function is represented in terms of more basic components of
processing.
- Transparency: pathological performance will provide a basis for interfering which
module is affected
- Universality: the model is true of normal human brain in general
-
Week 3: Phantom Limb
plasticity: changes in typical neural organisation (Synapses, pathways) as a function of
behavior, environment, injury
- Umbrella term that covers multitude of phenomena and changes (normal development,
long and short term changes in brain organization, brain chemistry)
- Includes both functional and structural changes occurring in the brain as result of
reorganization.
- may (2011) defines neuroplasticity as the environmentally driven constant
rearrangement of network homeostasis balancing the integration of neuronal activity,
neurotransmitter release, neuronal (perhaps glial) morphogenesis and changes in
network formation including formation and elimination of synaptic structures.
example:
- typical development: the brain rapidly reorganizes itself in the first few years of life
- expertise: musicians, evidence that the brain dedicates more space to those fingers that
play the instrument
- injury: loss of vision, evidence indicating that the brain may rededicate visual processing
areas to other sensory modalities (tactile)
o evidence of plasticity in sensory, motor, and occipital cortex in blind participatns
learning braille
after learning braille, the visual cortex becomes switched
- TMS can be used to examine the effects of visual and somatosensory cortex disruptions
of braille reading in blind indivudals to study the time course of information processing
o rTMS applied over the visual cortical area disrupts braille reading in blind
persons
o it can also induce tactile sensations in finger of braille readers
if inhibit sensorimotor cortex, cannot even detect so cant read
