Neurocognition lectures
Lecture 1 – the brain and cognition over the lifespan
Rebecca Schaefer
Brain structures and anatomy
!Be able to identify different parts of a neuron!
Different types of neurons are categorized by shape and function
- Sensory
- Interneurons
- Motor
Action potentials non-decremental: either there is an action potential
or there is not.
Synapse action potential leads to neurotransmitter release into synaptic
cleft
Receptor cells in the postsynaptic membrane can adapt to under- or over-
use
The distribution of synapses connecting to a cell influences its excitability
Glia cells
- Astrocytes
- Oligodendrocytes myelin for CNS neurons
- Microglial cells fight infections & waste disposal
- Ependymal cells ventricular surface epithelium, create CSF
- Schwann cells myelin for peripheral neurons
Cortical cell layers Where you are in the brain dictates how thick the
layers are
Bundles of myelinated axons
- Association fibres connect areas within a hemisphere
- Commissural fibers crossing to other hemisphere (homotopic or
heterotopic)
- Projection fibres connect outward to subcortical regions
Major components of the CNS
- Forebrain
- Hindbrain
o Medulla
o Pons
o Cerebellum
- Midbrain
o Colliculi
o Substantia nigra
, - Diencephalon thalamus, hypothalamus and pituary gland
Thalamus everything passes through
Un humans the forebrain has become exceptionally big.
- Subcortical structures
o Basal ganglia
Caudate nucleus
Putamen
Globus pallidus
Subthalamic nucleus (STN)
Substantia nigra
o Limbic system
Cingulate part of cortex
Hippocampus
Hypothalamus
Amygdala
Grey matter cell bodies
White matter connections
Basal ganglia circuits
- Motor circuit
- Associative circuit learning
- Reward circuit
Telencephalon cortical
- Frontal lobes movement, attention, reward, short-term memory,
planning, impulse control
- Parietal lobs sensory integration, association processes, language
functions, spatial processing, sense of touch, some visual processes
- Occipital lobes visual areas
- Temporal lobes memory, emotion association, primary auditory
areas, some visual
Functional asymmetries
- Language left-lateralized
- Global perception right lateralized
- Local perception left lateralized
Gyrus: bumps in the wrinkels
Sulcus: grooves in the wrinkels
recognizable landmarks
Open spaces in brain imaging ventricles of the brain
- lateral ventricles
- 3rd ventricle
- Aqueduct
, - 4th ventricle
- Central canal
Ventricular system and CSF
CSF runs through the
- Ventricles,
- Subarachnoid space
- Venous sinus
And is created in the
- Choroid plexus
- Ependymal cells
Membranes. Covering the brain and spinal cord
- Dura mater
- Arachnoid
- Pia mater
Naming conventions
- Brodmann areas histological: set up based on the kind of cells in
the areas, NOT what they are doing
- Functional names assumes one function per area
- Relative locations directional planes
- Coordinate systems most precise!
o X, y and z coordinates
o MNI coordinates based on “standard” brain
Brain development & plasticity
Cortical thickness relates to cognitive functioning according to studies
Cell development
- Dendritic spine formation sensitivity
- Neurogenesis allows new cells to come into existence into the
living brain, but only in specific places
, - Apoptosis pre-programmed cell-death (pruning)
Changes in healthy aging
- Cortical thinning/ atrophy
- Neuronal loss
- White matter lesions
- Inflammations
- Decrease in cerebral blood flow
- Beta-amyloid plaques
Fjell et al (2015) lot of change in young years compared to older
Stronger activation in older people compared to younger people
Gazzeleu et al (2005)
Cabeza et al (2004) reduced occipital activity and stronger parietal
and prefrontal activity for elderly
Bangert & Schlaug (2006) comparing string players (highly
developed motor skills in one hand) to pianists (two hands)
Functional pathways
- Visual
- Auditory
- Somatosensory
- Motor
Functional plasticity function can reorganize dynamically (visual
cortex is activated in blind individuals when reading braille)
Brain damage
- Normal aging
- Vascular stroke
- Trauma
- Tumors
- Developmental disorders
- Toxicity
- Infections
Most common occlusion site middle cerebral artery
Stroke:
- Ischemic: lack of oxygen
- Hemorrhagic: “leak”
Many TIAs white matter leasions
Trauma
Lecture 1 – the brain and cognition over the lifespan
Rebecca Schaefer
Brain structures and anatomy
!Be able to identify different parts of a neuron!
Different types of neurons are categorized by shape and function
- Sensory
- Interneurons
- Motor
Action potentials non-decremental: either there is an action potential
or there is not.
Synapse action potential leads to neurotransmitter release into synaptic
cleft
Receptor cells in the postsynaptic membrane can adapt to under- or over-
use
The distribution of synapses connecting to a cell influences its excitability
Glia cells
- Astrocytes
- Oligodendrocytes myelin for CNS neurons
- Microglial cells fight infections & waste disposal
- Ependymal cells ventricular surface epithelium, create CSF
- Schwann cells myelin for peripheral neurons
Cortical cell layers Where you are in the brain dictates how thick the
layers are
Bundles of myelinated axons
- Association fibres connect areas within a hemisphere
- Commissural fibers crossing to other hemisphere (homotopic or
heterotopic)
- Projection fibres connect outward to subcortical regions
Major components of the CNS
- Forebrain
- Hindbrain
o Medulla
o Pons
o Cerebellum
- Midbrain
o Colliculi
o Substantia nigra
, - Diencephalon thalamus, hypothalamus and pituary gland
Thalamus everything passes through
Un humans the forebrain has become exceptionally big.
- Subcortical structures
o Basal ganglia
Caudate nucleus
Putamen
Globus pallidus
Subthalamic nucleus (STN)
Substantia nigra
o Limbic system
Cingulate part of cortex
Hippocampus
Hypothalamus
Amygdala
Grey matter cell bodies
White matter connections
Basal ganglia circuits
- Motor circuit
- Associative circuit learning
- Reward circuit
Telencephalon cortical
- Frontal lobes movement, attention, reward, short-term memory,
planning, impulse control
- Parietal lobs sensory integration, association processes, language
functions, spatial processing, sense of touch, some visual processes
- Occipital lobes visual areas
- Temporal lobes memory, emotion association, primary auditory
areas, some visual
Functional asymmetries
- Language left-lateralized
- Global perception right lateralized
- Local perception left lateralized
Gyrus: bumps in the wrinkels
Sulcus: grooves in the wrinkels
recognizable landmarks
Open spaces in brain imaging ventricles of the brain
- lateral ventricles
- 3rd ventricle
- Aqueduct
, - 4th ventricle
- Central canal
Ventricular system and CSF
CSF runs through the
- Ventricles,
- Subarachnoid space
- Venous sinus
And is created in the
- Choroid plexus
- Ependymal cells
Membranes. Covering the brain and spinal cord
- Dura mater
- Arachnoid
- Pia mater
Naming conventions
- Brodmann areas histological: set up based on the kind of cells in
the areas, NOT what they are doing
- Functional names assumes one function per area
- Relative locations directional planes
- Coordinate systems most precise!
o X, y and z coordinates
o MNI coordinates based on “standard” brain
Brain development & plasticity
Cortical thickness relates to cognitive functioning according to studies
Cell development
- Dendritic spine formation sensitivity
- Neurogenesis allows new cells to come into existence into the
living brain, but only in specific places
, - Apoptosis pre-programmed cell-death (pruning)
Changes in healthy aging
- Cortical thinning/ atrophy
- Neuronal loss
- White matter lesions
- Inflammations
- Decrease in cerebral blood flow
- Beta-amyloid plaques
Fjell et al (2015) lot of change in young years compared to older
Stronger activation in older people compared to younger people
Gazzeleu et al (2005)
Cabeza et al (2004) reduced occipital activity and stronger parietal
and prefrontal activity for elderly
Bangert & Schlaug (2006) comparing string players (highly
developed motor skills in one hand) to pianists (two hands)
Functional pathways
- Visual
- Auditory
- Somatosensory
- Motor
Functional plasticity function can reorganize dynamically (visual
cortex is activated in blind individuals when reading braille)
Brain damage
- Normal aging
- Vascular stroke
- Trauma
- Tumors
- Developmental disorders
- Toxicity
- Infections
Most common occlusion site middle cerebral artery
Stroke:
- Ischemic: lack of oxygen
- Hemorrhagic: “leak”
Many TIAs white matter leasions
Trauma
