Jan 14th 2014 Ch2/3: Cognitive Neuroscience and Perception Week 2
Describe structure and function of a neuron
Review major anatomical divisions of the brain
Introduce theories of object recognition
Compare object vs. facial recognition
KEY THEMES OF ANATOMY
1. Structure vs. Function
2. Localization vs. Distributed Processing
Soma – cell body, live sustaining
Dendrites- receives info.
Axon: info travels down through
Myelin: insulates the action
- The range and size of axon varies.
Electrical signals reaches terminal button,
release neurotransmitters across the synapse.
They neurotransmitters bind to the post synapse.
This causes an excited or inhibitory
Information is conveyed chemically at the
The majority of neurotransmitters can be
classified into 3 categories:
Amino acids (e.g. GABA-
inhibitory neurotransmitter- ON single; glutamate-
Primary excitatory neurotransmitter- ON single
Monoamine (e.g. DA, NE, 5-
HT)- get the brain ready to response.
(enkephalins- stopping feeling of pain; substance
P- signals pain)
Stimulus intensity is represented by the Spontaneous firing
firing rate of neurons Excitatory activity
inhibitory Jan 14th 2014 Ch2/3: Cognitive Neuroscience and Perception Week 2
All cells have some action if they receive
signals or not. There are action potentials
happening even when at rest.
A very strong signal is indicated by a lot of
Techniques used to investigate structure:
Post-mortem investigation: oldest and only way at one point in time. Wait for
someone to die.
CT: an X-ray of different angles that gives us an image of the brain.
MRI: Much clearer (high spatial resolution) picture than a CT.
Techniques used to investigate function:
Single-cell recording/stimulation/lesions/TMS- exclusively on humans, allows
temp lesion. Handheld device of magnetic devise and it lesions a certain part of
the brain: record activity from an individual brain cell. Insert electrode and record
brain wave. ONLY DONE IN ANIMALS.
EEG- measures the electrical potential of the brain as a whole. / ERP- measure
EEG with an event related change. Looking for when the change occur. Can tell
WHEN the brain is processing, but not WHERE (Spatial resolution) /MEG-
measures magnetic fields. Excellent temporal and spatial resolution
PET: measures blood flow/ metabolic function. Insert radioactive die to enter
blood system. Active part of the brain requires more blood and will show up more
on the scan. Relatively poor spatial and temporal resolution.
FMRI: causes hydrogen to wiggle and you measure the energy produced. Takes
advantages of the fact that oxygenated and deoxygenated have different
residence. Much better spatial than pet but still not good temporal resolution.
When brain activity is measured, it need to be compared to baseline activity.
The subtraction technique used to interpret the results of brain imaging experiments. (a)
Colored area indicates activation when a person is holding a small object. (b) Colored
areas indicate activation when the person begins manipulating the object. (c) Subtracting
the activation in (a) from the activation in (b) indicates the activation due to manipulation
of the object.
BRAIN STRUCTURE & FUNCTION
There are a number of ways we can
discuss brain structure:
Developmental areas Jan 14th 2014 Ch2/3: Cognitive Neuroscience and Perception Week 2
We describe different parts of the brain
based on directions from the spinal cord.
An imaginary line running down the middle
of the spinal cord is called the midline
Imagine a rat:
The same system applies in humans
The brain is divided into sections based on
how it develops
Cerebellum: fine motor control- finger
control or reaching/ posture imbalance-
Pons: relay station. Conveys between
cerebellum and cerebral.
Medulla: Important for basic life
sustaining system- muscle tone/ cardio
vascular Jan 14th 2014 Ch2/3: Cognitive Neuroscience and Perception Week 2
Tectum (“roof”): groups of cells important for visual and auditory reflexes
Tegmentum (“floor”): contains groups of cells that releases dopamine and motor control.
FOREBRAIN: Diencephalon (red)
Hypothalamus: endocrine functions , involved in autonomic system: thirst, hunger,
Thalamus: Sensory station- modueling sensory info. Important for arousal: alert and
• Basal ganglia: important for
Limbic system: emotions.
Hippocampus is also part of limbic
system, it is important for memory.
Cerebral cortex: grey matter outside of
brain. Responsible for higher level of
The cerebral cortex is folded over
itself to create gyri (bumps) and sulci
The cortex is divided into 4 lobes
Parietal: Sense of touch and attention.
Temporal: Auditory cortex, language
comprehension, object recognition.
Frontal: motor cortex, broca’s area for speech
production, highest level of thinking: planning,
thinking, decision making.
Cortex can be
according to physical
arrangement of gyri
and sulci Jan 14th 2014 Ch2/3: Cognitive Neuroscience a