Brain Regions Flashcards
6 Brain Regions in Visual Cognition
IT - Inferior Temporal Cortex
PPC - Posterior Parietal Cortex)
FFA/PPA - Fusiform Face Area / Parahippocampal Place Area
OFA - Occipital Face Area
LOC - Lateral Occipital Complex
STS - Superior Temporal Sulcus
PPA: Parahippocampal Place Area
Function: Specialized area in the
inferotemporal cortex associated with the
perception and processing of scenes/places
OFA: Occipital Face Area
Function: Specialized area in the occipital
cortex associated with early processing of
facial features.
LOC: Lateral Occipital Complex
Function: Involved in object recognition and
processing of complex visual stimuli, including
shapes and objects.
STS: Superior Temporal Sulcus
Function: Associated with processing social
cues such as facial expressions, eye gaze, and
biological motion, as well as aspects of language
processing and multisensory integration.
Posterior Parietal Cortex (PPC):
Integrates visual information with
spatial awareness and plays a role in
guiding actions based on visual input
(e.g., reaching for an object).
Inferior Temporal Cortex (IT):
Critical for object recognition and the
association of visual input with stored
memories and concepts. Lesions result in
visual agnosia
Describe what is meant with contralateral control of vision
Fact that left side
of the brain is being stimulied by right hemifield
and vice versas.
However, only the information from the left h
emifield of the left eye has to cross and the right
hemifield of the right eye has to cross
Describe the flow of vision in the brain
A. Left Hemretina**
B. Optic Nerve
C. Optic Chiasma
D. LGN
E. Primary Visual Cortex
What are simple cells
Respond to oriented edges or bars of light within a specific receptive field. They have a characteristic receptive field
structure with distinct regions of excitatory and inhibitory response to light stimuli oriented at specific angles.
Selective for the orientation, spatial frequency, and location of visual stimuli.
What are complex cells
Unlike simple cells, complex cells do not have distinct regions of excitatory and inhibitory response within their receptive
fields. They respond to oriented edges or bars of light moving in a particular direction within a larger receptive field.
● exhibit properties such as spatial and temporal integration, allowing them to respond to moving visual stimuli in specific
orientations.
● less sensitive to the exact location of visual stimuli
● more tuned to motion direction and speed.
Difference between single and double association
Single
● this is done by demonstrating that a lesion to brain
structure A disrupts function X but not function Y
(Some Lesion disrupts one region but not clear what else is happening;
e.g. Broca’s aphasia -> cant speak but comprehension is intact, so we
know that comprehension is somewhere but we dont know where until
we investigate that region)
Double
● If one can demonstrate that a lesion in brain
structure A impairs function X but not Y,
and further demonstrate that a lesion to
brain structure B impairs function Y but
spares function X, one can make more
specific inferences about brain function and
function localization
(Wernicke: speak totally fine but cant comprehend
-> we combine Broca and Wernicke and know that
two brain regions are responsible for different topics)
V1 and V2
Receives raw visual input from the
eyes.
Responsible for basic processing of
visual stimuli, such as edge detection
and simple feature recognition
V2 Receives processed information from
V1.
Describe the Dorsal Stream
V3: Further processes visual information,
including motion detection.
V3A: Involved in the perception of object shape
and size.
V5/MT (Middle Temporal Area): Specializes in
motion perception and the analysis of visual
motion cues.
Describe the Vental Stream
V4: Responsible for color perception and object
recognition, including the identification of
complex shapes and colors.
V8: Involved in the processing of visual illusions
and complex visual stimuli.
Describe Depolarization, Repolarization and Hyperpolarization
–P- re-Post Synaptic
Neurotransmitter in synaptic cleft create EPSP or IPSP
–Change in Ion Channel Structure
NA+ (EPSP, depolarized) or CL- (IPSP hyperpolarized) channel are open
–Sum of exotatory inputs (Na+ go in the cell through Ion gates) lead to reach threshold of -50mV and create action potential
Change in Volt up to 40mV.
– Sodium Channels close and Repolarisation starts
– At -70mV Potassium channels close, however takes a bit of time and hyperpolarization occurs until resting state is achieved
6 Brain Methodologies
fMRI Functional Magnetic Resonance Imaging
EEG Electroencephalography
TMS Transcranial Magnetic Stimulation
ERP Event-Related Potentials
PET Positron Emission Tomography
MEG Magnetoencephalography
fMRI Functional Magnetic Resonance Imaging
BOLD signal measures changes in the ratios of oxygenated to deoxygenated hemoglobin in the brain. Low temporal resolution
(compared to EEG or MEG). High spatial resolution. Low invasivity.
EEG Electroencephalography
Records electrical activity generated by neurons in the brain using electrodes placed on the scalp. Good temporal resolution.
Moderate spatial resolution. Non-invasive.
TMS Transcranial Magnetic Stimulation
Applies brief magnetic pulses to the scalp to induce electrical currents in the brain. Can modulate brain activity. Temporal
resolution depends on application. Low spatial resolution.
ERP Event-Related Potentials
Measures brain responses to specific events or stimuli by analyzing EEG data time-locked to the event. Good temporal
resolution. Moderate spatial resolution. Non-invasive.
PET Positron Emission Tomography
Positron Emission Tomography
Measures metabolic activity (including Neurotransmitters) in the brain by detecting radioactive tracers injected into the bloodstream. Low temporal
resolution. Moderate spatial resolution. Invasive
MEG Magnetoencephalography
Records magnetic fields produced by neural activity in the brain. Good temporal resolution. Moderate spatial resolution.
Non-invasive.
Describe the Brain Atlas
X = Sagittal
Y = Horizontal
Z = Coronal
Where is Sylvian Fissure and Central Sulcus
Sylvian Fissure: Between Prefontral Cortex and Temporal Lobe
Central Sulcus: Between Motor Cortex and Primary Somatosensory Cortex
Brocas Aphasia
Brocas - nonfluent or expressive aphasia
● nonfluent aphasia
● damage that primarily affects the frontal lobe
● limited language. You might only be able to say
single words or very short sentences
● when people find it very difficult to find and say
the right words, although they probably know
exactly what they want to say.
● People with Broca’s aphasia may only be able to
say single words or very short sentences
● TAN
Wernicke’s - receptive aphasia
● causes you to speak in a jumbled “word
salad” that others can’t understand.
● when someone is able to speak well and use
long sentences, but what they say may not
make sense.
● may not know that what they’re saying is
wrong, so may get frustrated when people
don’t understand them.
Sprachstörung
Patient TAN
Wernicke’s - receptive aphasia
causes you to speak in a jumbled “word
salad” that others can’t understand.
● when someone is able to speak well and use
long sentences, but what they say may not
make sense.
● may not know that what they’re saying is
wrong, so may get frustrated when people
don’t understand them.
