Neuropsychology and psychopharmacology – Noa Daems
NEUROPSYCHOLOGY AND
PSYCHOPHARMACOLOGY
LES 1 : INTRODUCING COGNITIVE NEUROSCIENCE + THE LESIONED BRAIN
HF 1 : INTRODUCING COGNITIVE NEUROSCIENCE
MIND AND BRAIN : AN EMPIRICAL EXAMPLE
- Wilder Penfield (1891–1976) was a famous neurosurgeon and neuroscientist.
- He pioneered brain surgery techniques for epilepsy treatment.
➔ During operations, he electrically stimulated parts of the cerebral cortex while
patients were awake (under local anesthesia) to identify and spare regions of the
brain involved in movement and sensation
- Patients reported vivid sensations, memories, or movements depending on the
stimulated area
➔ From this, Penfield mapped the “cortical homunculus”..
COGNITIVE NEUROSCIENCE
- Cognitive neuroscience aims to provide a brain-based account of
cognitive and behavioral processes (perceiving, remembering etc.)
- Made possible by technological advances in studying the brain that
are safer and less crude than, say, Penfield’s method
- The term cognition refers to a variety of higher mental processes such as thinking,
perceiving, imagining, speaking, acting and planning
HISTORICAL FOUNDATIONS
- Do mental experiences arise in the heart (e.g., Aristotle) or brain (e.g., Plato)?
- Mind-body problem: How can a physical substance (brain/body) give rise to mental
experience?
1. dualism : mind and body are separate substances (René Descartes)
➔ He believed that the mind was nonphysical and immortal, whereas the body was
physical and mortal
Physical and non-physical interact in pineal gland. Sense organs, then
vibrations in brain, and creates non-physical sense of awareness
2. dual-aspect theory : mind and body are two levels of explanation of the same thing
(Spinoza)
1
,Neuropsychology and psychopharmacology – Noa Daems
3. reductionism : mind eventually explained solely in terms of physical/biological theory
(Churchland) – the belief that mind based concepts will eventually replaced by
neuroscientific concepts
➔ Our current level of understanding is closest to dual-aspect theory.
SCIENTIFIC APPROACHES TO MIND AND BRAIN
- Aristotle noted that the ratio of brain size tot body size was greatest in more
intellectually advanced species, such as humans
➔ Made an error of claiming that cognition was a product of the heart rather than
the brain
Believed that the brain acted as a coolant system: the higher the intellect, the
larger the cooling system needed
- Galen, in the Roman age, observed brain injury in gladiators and noted that
nerves project to and from the brain
➔ Believed that mental experiences themselves resided in the ventricles of
the brain
This idea went essentially unchallenged for well of 1,500 years
- Vesalius published his plates of dissected brains → the ventricles were drawn
in exacting detail, whereas the cortex was drawn crudely and schematically
- Early anatomists believed ventricles were important
- Cortex was often schematically drawn (top) or misrepresented like intestines
until 18th century
- Gall and Spurzheim (1810) provide an accurate depiction of the features of
the brain → invention of phrenology
PHRENOLOGY
- Different parts of cortex serve different functions
- Differences in personality traits manifest in differences in cortical size and
bumps on skull
➔ Taking these two ideas in turn, the notion of functional specialization within
the brain has effectively endured into modern cognitive neuroscience
- Crude division of psychological traits (e.g. "love of animals")
None of these was grounded in science but the first turned out to be
correct
- Although phrenology is discredited, the notion that different regions of the brain serve
different functions has stood the test of time
- Modern cognitive neuroscience uses empirical NEUROSCIENCE methods to ascertain
different COGNITIVE functions.
- It does not assume that each region has one function, or that each function has a
discrete location (unlike phrenology), but does assume and empirically shows some
degree of functional specialization
-
FUNCTIONAL SPECIALIZATION : BROCA’S OBSERVATIONS
- Paul Broca (1861) : reported two brain-damaged patients
➔ Documented these two cases in which acquired brain damage had impaired the
ability to speak but left other aspects of cognition relatively intact
➔ Concluded that language could be localized to a particular region of the brain
2
,Neuropsychology and psychopharmacology – Noa Daems
- Subsequent studies argued that language itself was not a single entity but could
further subdivided intro speech recognition, speech production and conceptual
knowledge
➔ This suggests that there are at least two speech faculties in the brain and that
each can be independently impaired by brain damage
FUNCTIONAL SPECIALIZATION : AFTER BROCA
- Wernicke later observed a patient with poor speech comprehension, but good
production
- Suggests at least two language faculties in the brain (comprehension vs production)
that can be independently affected by brain damage
- This inference can be made without necessarily knowing where in the brain they are
located
- The notion that the brain contains different regions of functional specialization has
been around in various guises for 200 years
FODOR’S THEORY OF MODULARITY
- He makes a distinction between two different classes of cognitive processes : central
systems and modules
➔ the key difference between them relates to the type of information they can
process
1. modules are held to demonstrate domain specificity in that they process only
one particular type of information
2. central systems are held to be domain independent in that the type of
information is notspecific
LOBES OF THE BRAIN
- The sphenoid bone is: a complex, butterfly-shaped bone at the base of the skull,
behind the eyes and above the nasal cavity
MAPS OF THE BRAIN
3
, Neuropsychology and psychopharmacology – Noa Daems
MINDS WITHOUT BRAINS : THE COMPUTER METAPHOR
- Much of twentieth-century psychology was concerned with observations of behavior,
rather than observations of the brain during behavior.
- This led to models of cognition that do not make direct reference to the brain, e.g.
the information-processing models popular from the 1950s onwards
- The models were inspired by thinking of the mind as a series of routines, like those
found in computers
4
NEUROPSYCHOLOGY AND
PSYCHOPHARMACOLOGY
LES 1 : INTRODUCING COGNITIVE NEUROSCIENCE + THE LESIONED BRAIN
HF 1 : INTRODUCING COGNITIVE NEUROSCIENCE
MIND AND BRAIN : AN EMPIRICAL EXAMPLE
- Wilder Penfield (1891–1976) was a famous neurosurgeon and neuroscientist.
- He pioneered brain surgery techniques for epilepsy treatment.
➔ During operations, he electrically stimulated parts of the cerebral cortex while
patients were awake (under local anesthesia) to identify and spare regions of the
brain involved in movement and sensation
- Patients reported vivid sensations, memories, or movements depending on the
stimulated area
➔ From this, Penfield mapped the “cortical homunculus”..
COGNITIVE NEUROSCIENCE
- Cognitive neuroscience aims to provide a brain-based account of
cognitive and behavioral processes (perceiving, remembering etc.)
- Made possible by technological advances in studying the brain that
are safer and less crude than, say, Penfield’s method
- The term cognition refers to a variety of higher mental processes such as thinking,
perceiving, imagining, speaking, acting and planning
HISTORICAL FOUNDATIONS
- Do mental experiences arise in the heart (e.g., Aristotle) or brain (e.g., Plato)?
- Mind-body problem: How can a physical substance (brain/body) give rise to mental
experience?
1. dualism : mind and body are separate substances (René Descartes)
➔ He believed that the mind was nonphysical and immortal, whereas the body was
physical and mortal
Physical and non-physical interact in pineal gland. Sense organs, then
vibrations in brain, and creates non-physical sense of awareness
2. dual-aspect theory : mind and body are two levels of explanation of the same thing
(Spinoza)
1
,Neuropsychology and psychopharmacology – Noa Daems
3. reductionism : mind eventually explained solely in terms of physical/biological theory
(Churchland) – the belief that mind based concepts will eventually replaced by
neuroscientific concepts
➔ Our current level of understanding is closest to dual-aspect theory.
SCIENTIFIC APPROACHES TO MIND AND BRAIN
- Aristotle noted that the ratio of brain size tot body size was greatest in more
intellectually advanced species, such as humans
➔ Made an error of claiming that cognition was a product of the heart rather than
the brain
Believed that the brain acted as a coolant system: the higher the intellect, the
larger the cooling system needed
- Galen, in the Roman age, observed brain injury in gladiators and noted that
nerves project to and from the brain
➔ Believed that mental experiences themselves resided in the ventricles of
the brain
This idea went essentially unchallenged for well of 1,500 years
- Vesalius published his plates of dissected brains → the ventricles were drawn
in exacting detail, whereas the cortex was drawn crudely and schematically
- Early anatomists believed ventricles were important
- Cortex was often schematically drawn (top) or misrepresented like intestines
until 18th century
- Gall and Spurzheim (1810) provide an accurate depiction of the features of
the brain → invention of phrenology
PHRENOLOGY
- Different parts of cortex serve different functions
- Differences in personality traits manifest in differences in cortical size and
bumps on skull
➔ Taking these two ideas in turn, the notion of functional specialization within
the brain has effectively endured into modern cognitive neuroscience
- Crude division of psychological traits (e.g. "love of animals")
None of these was grounded in science but the first turned out to be
correct
- Although phrenology is discredited, the notion that different regions of the brain serve
different functions has stood the test of time
- Modern cognitive neuroscience uses empirical NEUROSCIENCE methods to ascertain
different COGNITIVE functions.
- It does not assume that each region has one function, or that each function has a
discrete location (unlike phrenology), but does assume and empirically shows some
degree of functional specialization
-
FUNCTIONAL SPECIALIZATION : BROCA’S OBSERVATIONS
- Paul Broca (1861) : reported two brain-damaged patients
➔ Documented these two cases in which acquired brain damage had impaired the
ability to speak but left other aspects of cognition relatively intact
➔ Concluded that language could be localized to a particular region of the brain
2
,Neuropsychology and psychopharmacology – Noa Daems
- Subsequent studies argued that language itself was not a single entity but could
further subdivided intro speech recognition, speech production and conceptual
knowledge
➔ This suggests that there are at least two speech faculties in the brain and that
each can be independently impaired by brain damage
FUNCTIONAL SPECIALIZATION : AFTER BROCA
- Wernicke later observed a patient with poor speech comprehension, but good
production
- Suggests at least two language faculties in the brain (comprehension vs production)
that can be independently affected by brain damage
- This inference can be made without necessarily knowing where in the brain they are
located
- The notion that the brain contains different regions of functional specialization has
been around in various guises for 200 years
FODOR’S THEORY OF MODULARITY
- He makes a distinction between two different classes of cognitive processes : central
systems and modules
➔ the key difference between them relates to the type of information they can
process
1. modules are held to demonstrate domain specificity in that they process only
one particular type of information
2. central systems are held to be domain independent in that the type of
information is notspecific
LOBES OF THE BRAIN
- The sphenoid bone is: a complex, butterfly-shaped bone at the base of the skull,
behind the eyes and above the nasal cavity
MAPS OF THE BRAIN
3
, Neuropsychology and psychopharmacology – Noa Daems
MINDS WITHOUT BRAINS : THE COMPUTER METAPHOR
- Much of twentieth-century psychology was concerned with observations of behavior,
rather than observations of the brain during behavior.
- This led to models of cognition that do not make direct reference to the brain, e.g.
the information-processing models popular from the 1950s onwards
- The models were inspired by thinking of the mind as a series of routines, like those
found in computers
4
