exam 1 Flashcards
Better ratio of photoreceptors to ganglion cells in the fovea than in the periphery
The fovea is the part of the retina that contains a high density of _______, which is why this is the region of the retina with the greatest visual acuity.
Cones
The optic nerve projects to the
lateral geniculate nucleus of the thalamus
Transcranial Magnetic Stimulation (TMS)
Temporarily activates or deactivates brain regions on the surface of the brain using a magnetic pulse
Single-Unit Recording
Electrode records electrical activity from specific neurons in the brain during activity/behavior
Magnetoencephalography (MEG)
Magnetometer at the scalp measures magnetic fields generated by active neurons
Magnetic Resonance Imaging (MRI)
Hydrogen atoms aligned by powerful magnet
Radio frequency pulse disrupts alignment of unmatched atoms
As atoms re-align they emit energy
Because tissues differ in hydrogen concentration they emit different amounts of energy resulting in acquired images
fMRI (functional magnetic resonance imaging)
Measures changes in blood oxygenation
Active areas of the brain require more oxygen from blood
TMS cannot stimulate subcortical structures
MRI scans detect brain structures, not activity
Patients with lesions may not respond the same way as typical adults
fMRI detects location but is not time sensitive
PET is invasive and has very poor temporal resolution
ERPs are sensitive to time, not location
A disadvantage of ERP compared to functional neuroimaging is that with ERPs it is hard to:
determine the exact brain region where changes in activity originate from
A researcher wants to know if the size of the hippocampus correlates with spatial navigation abilities. What method should the researcher use?
MRI
Cortical organization is contralateral
The left side of the body or perceptual world has more representation on the right side of the brain, and vice versa
If a researcher applies mild electric current to a specific area of an animal’s right hemisphere primary motor projection area, which of the following is likely to happen?
A specific movement of a body part on the side of the animal
Joe is a split brain patient. He is presented with a picture of a pencil in his right visual field. Which of the following can Joe do?
Reach for the pencil with his left hand
Reach for the pencil with his right hand
Perceptual qualities of color
Hue
Saturation
Brightness
Cerebral Achromatopsia
Damage to V4
Disrupted color perception and imagery
Interposition
Nearer objects hide more distant ones
Familiar size
We can use the size of familiar objects to judge distance
Motion parallax
Objects in the foreground appear to move more than objects in the background
Convergence
The eyes turn inward more to focus on close than distant objects
Stereopsis
The difference in the retinal image between the eyes serves as a depth cue
Visual Imager
Top-down
Representation imagery
Damage to temporal lobe can selectively disrupt imagery
Visual Perception
Bottom-up
Stimulus perception
Damage to visual cortex
can selectively disrupt perception
cognitive psychology
an approach that aims to understand human cognition by the study of behaviour.
cognitive neuroscience
an approach that aims to understand human cognition by combining information from behaviour and the brain.
positron emission tomography (PET):
a
brain-scanning technique based on the detection of positrons; it has reasonable spatial resolution but poor temporal resolution
functional magnetic resonance imaging (fMRI
a technique based on imaging blood oxygenation using an MRI machine; it provides information about the location and time course of brain processes.
bottom-up processing
processing that is directly influenced by environmental stimuli
Cognitive neuropsychology
an approach that involves studying cognitive functioning in braindamaged patients to increase our understanding of normal human cognition
ecological validity
the extent to which experimental findings are applicable to everyday settings.
serial processing
processing in which one process is completed before the next one starts
top-down processing
stimulus processing that is influenced by factors such as the individual’s past experience and expectations
parallel processing:
processing in which two or more cognitive processes occur at the same time
paradigm specificity
this occurs when the findings obtained with a given paradigm or experimental task are not obtained even when apparently very similar paradigms or tasks are used.
sulcus
a groove or furrow in the brain.
gyri (“gyrus” is the singular),
ridges in the brain
cytoarchitectonic map
a map of the brain based on variations in the cellular structure of tissues.
single-unit recording
an invasive technique for studying brain function, permitting the study of activity in single neurons
electroencephalogram (EEG)
a device for recording the electrical potentials of the brain through a series of electrodes placed on the scalp.
event-related potentials (ERPs):
the pattern of electroencephalograph (EEG) activity obtained by averaging the brain responses to the same stimulus presented repeatedly.
BOLD: blood oxygen-level-dependent contrast;
this is the signal that is measured by fMRI
event-related functional magnetic imaging (efMRI):
this is a form of functional magnetic imaging in which patterns of brain activity associated with specific events (e.g., correct versus incorrect responses on a memory test) are compared.
magneto-encephalography (MEG):
a non-invasive brain-scanning technique based on recording the magnetic fields generated by brain activity.
transcranial magnetic stimulation (TMS):
a technique in which magnetic pulses briefly disrupt the functioning of a given brain area, thus creating a short-lived lesion; when several pulses are administered one after the other, the technique is known as repetitive transcranial magnetic stimulation (rTMS)
repetitive transcranial magnetic stimulation (rTMS
the administration of transcranial magnetic stimulation several times in rapid succession
functional specialisation
the assumption that each brain area or region is specialised for a specific function (e.g., colour processing; face processing).
modularity
the assumption that the cognitive system consists of several fairly independent processors or modules
domain specificity
the notion that a given module or cognitive process responds selectively to certain types of stimuli (e.g., faces) but not others.
dissociation
as applied to brain-damaged patients, normal performance on one task combined with severely impaired performance on another task.
double dissociation
the finding that some individuals (often brain-damaged) do well on task A and poorly on task B, whereas others show the opposite pattern
association
concerning brain damage, the finding that certain symptoms or performance impairments are consistently found together in numerous brain-damaged patients
syndromes
labels used to categorise patients on the basis of co-occurring symptoms
computational cognitive science
an approach that involves constructing computational models to understand human cognition. Some of these models take account of what is known about brain functioning as well as behavioural evidence
computational modelling
this involves constructing computer programs that will simulate or mimic some aspects of human cognitive functioning
connectionist networks
these consist of elementary units or nodes, which are connected; each network has various structures or layers (e.g., input; intermediate or hidden; output).
back-propagation
a learning mechanism in connectionist networks based on comparing actual responses to correct ones.
retinotopic map
nerve cells occupying the same relative positions as their respective receptive fields have on the retina.
achromatopsia
this is a condition involving brain damage in which there is little or no colour perception, but form and motion perception are relatively intact.
akinetopsia
this is a brain-damaged condition in which stationary objects are perceived reasonably well but objects in motion cannot be perceived accurately.
binding problem
the issue of integrating different kinds of information during visual perception.
optic ataxia
a condition in which there are problems with making visually guided limb movements in spite of reasonably intact visual perception.
visual agnosia
a condition in which there are great problems in recognising objects presented visually even though visual information reaches the visual cortex.
microspectrophotometry
a technique that allows measurement of the amount of light absorbed at various wavelengths by individual cone receptors.
dichromacy
a deficiency in colour vision in which one of the three basic colour mechanisms is not functioning.
negative afterimages
the illusory perception of the complementary colour to the one that has just been fixated for several seconds; green is the complementary colour to red, and blue is complementary to yellow.
colour constancy
the tendency for any given object to be perceived as having the same colour under widely varying viewing conditions
chromatic adaptation
reduced sensitivity to light of a given colour or hue after lengthy exposure.
blindsight
the ability to respond appropriately to visual stimuli in the absence of conscious vision in patients with damage to the primary visual cortex.
Emmert’s law
the size of an afterimage appears larger when viewed against a far surface than when viewed against a near one.
monocular cues
cues to depth that can be used with one eye, but can also be used with both eyes.
binocular cues
cues to depth that require both eyes to be used together
oculomotor cues:
kinaesthetic cues to depth produced by muscular contraction of the muscles around the eye.
motion parallax
movement of an object’s image across the retina due to movements of the observer’s head.
convergence
one of the binocular cues, based on the inward focus of the eyes with a close object.
accommodation
one of the binocular cues to depth, based on the variation in optical power produced by a thickening of the lens of the eye when focusing on a close object.
stereopsis:
one of the binocular cues; it is based on the small discrepancy in the retinal images in each eye when viewing a visual scene
binocular disparity
the slight discrepancy in the retinal images of a visual scene in each eye; it forms the basis for stereopsis.
wallpaper illusion
a visual illusion in which staring at patterned wallpaper makes it seem as if parts of the pattern are floating in front of the wall.
autostereogram:
a complex two-dimensional image that is perceived as three-dimensional when it is not focused on for a period of time.
size constancy
objects are perceived to have a given size regardless of the size of the retinal image
Amygdala
Emotion (especially fear) processing
Cerebellum
Motor coordination, posture, some cognitive functions (e.g., memory)
Hypothalamus
Homeostatic functions (hunger, thirst, sleep, fighting, mating, ANS regulation)
Hippocampus
memory
Frontal lobe
Higher order cognitive functions (e.g., planning, executive functions, judgment)
Occipital lobe
Vision
Parietal lobe
Attention, somatosensation, spatial processing, memory
Temporal lobe
Audition, object recognition, language
Thalamus
Sensory relay station
