An Introduction to human cognition Flashcards
Cognitive Psychology:Explain the information processing approach
the assumption human processing is similar to computers
Cognitive Psychology:Explain the bottom-up serial processing
processing is directly influenced by environmental stimuli (serial=1 process at a time) and is emphasised
Cognitive Psychology:Explain the Top-Down processing
processing is influenced by knowledge and expectations (is de-emphasised)
What are the strengths of cognitive psychology?
-it’s the first systematic approach
-it led to several theories/tasks adopted by other approaches
-flexible and can be applied to any aspect of cognition
-more efficient + less likely to have errors made
What are the limitations of cognitive psychology?
-some cognitive tasks impure and lack ecological validity
-indirect evidence of underlying processes
-vague hard to test theories
-findings often paradigm specific
-lack of an overarching theoretical framework
Define cognitive neuropsychology
the evaluation of cognitive performance in brain-damaged patients which can provide direct evidence of brain-cognition linkages. (but can’t fully predict what an individual can do)
What are the key assumptions of cognitive neuropsychology?
1.functional modularity
2.anatomical modularity
3.universality assumption
4.subtractivity
Define functional modularity
the independent processing units which exhibit domain specificity (response to one class of stimuli only)
Define anatomical modularity
each cognitive module is located in a specific brain region
Define universality assumption
the organisation of cognitive functions are similar across all individuals
Define subtractivity
brain damage only disrupts modules or connections between them and new modules are NOT developed to compensate in patients
How does cognitive neuropsychology use correlational evidence?
via associations which occur when a patient is impaired on both tasks and can often be used to identify syndromes(where certain sets of symptoms or impairments are found)
How does Cognitive neuropsychology use single case studies?
-single patient used
-are they an outlier or representative?
-useful for rare forms of brain damage
How does Cognitive neuropsychology use case-series studies?
-studies several patients with similar symptoms/damage
-much richer data
-can identify extent of variation across patients
Define network organisation in cognitive neuroscience
the human brain has complex topology with moderate cost control + efficiency
Define cognitive neuroscience
the study of how the brain enables the mind biologically and cognitively
Explain the principle of cost-control and efficiency
CC-few long distance connections
E-the ability to integrate information across the brain
Explain the technique of single-unit recording
a micro electrode is inserted into the brain and records activity from a single neuron.
Give an advantage of single-unit recordings
has high temporal and spatial resolution
Give three disadvantages of single-unit recordings
-highly invasive and requires surgery which could damage the cells across the electrodes path
-expensive
-too narrow to assess the most higher cognitive processes
What is the technique used for ERPs?
-most common is the electrodes on the scalp which captures changes in potential allowing where/when the brain is active (300ms)
What are the advantages of ERPs?
-Electrical activity on scalp is recorded during repeated events where brain waves are segmented and then averaged
-good temporal resolution
-provides a detailed continous record of brain activity
What are the disadvantages of ERPs?
-limited spatial resolution as skull/brain tissue distorts electrical fields
-numerous trials required
-hard to study complex cognition as processes/strategies change over trials
Explain the technique used PET scans
water containing a radioactive tracer emits positrons where water rushes to an active brain region and the scanning device measures the positrons emitted.
Give an advantage of PET scans
spatial is reasonable (5-10mm)
Give 2 disadvantages of PET scans
-poor temporal resolution as it detects regional blood flow changes on the order of 30-60s
-invasive as introduction of radioactive substances has limited its frequency of usage
Explain the technique used in fMRI
non-invasive measure of brain activity (where it’s happening whereas EEG/ERP is when it’s happening) and in efMRI(event-related fMRI) patterns of brain activity associated with specific events are compared. (doesn’t measure neural activity but correlator activity i.e. the response of blood to magnetic fields spotting neurons location where oxygen is delivered)
Give an advantage of fMRI scans
good spatial resolution (approx 1mm)
Give 5 disadvantages of fMRI scans
-expensive
-poor temporal resolution (2-3s)
-indirect measure of brain activity
-distortions in some brain regions
-constraints on stimuli that can be presented
Explain the technique used in TMS
a brief pulse is emitted by a coil next to the skull where magnetic field disrupts the brain activity/neurons in the underlying cortex to determine whether certain brain areas responsible for certain tasks prevented=yes
Give 5 limitations of TMS
-could cause visual hallucinations
-TMS effects complex and not fully understood
-it can enhance performance due to compensatory flexibility recruiting other brain areas
-brain areas not directly targeted by TMS may also be affected
-limited to brain areas lying beneath the skull + with overlying muscle
Give an advantage of TMS
one of the techniques where you can prove causality (better scientifically wise)
Give 5 strengths of cognitive neuroscience
-combo of techniques gives good spatial/temporal resolution
-provides rich info to add to behavioural measures
-helped to resolve many theoretical controversies
-meta-analysis 10,000+ have clarified brain-cognition relationships
-limitations of functional specialisation assumption identified
Explain the MEG technique
uses a superconducting quantum interference device aka SQUID and measures the magnetic fields produced by brain activity
Give an advantage of MEG technique
good spatial/temporal resolution
Give 3 limitations of MEG
-very expensive
-requires patients to be in a potential uncomfortable body position for long periods of time
-technology and analysis relatively new and complicated
Give 6 limitations of Cognitive neuroscience
-deterministic
-over-interpreted findings (not necessarily direct evidence to cognitive processes)
-“neuroenchantment” (exaggerated respect for findings in CN)
-underpowered studies
-false reported positive studies
-difficulty relating brain activation to cognitive processes
Explain how visual information is processed
Visual information forwarded primarily to visual areas located in the back of the brain (visual areas) to then starts being processed
-destruction of neurons in visual areas=blindness
what are some neurons/areas of the cortex responsive too?
neurons=lines (thought to store visual shapes of objects)
cortex=objects e.g. buildings,faces
How do we know the shape of objects?
-perception/knowledge is stored in memory
-recognising the object is matching what we see with what we know so we detect visual patterns to structure a visual scene
Why can’t we change what we see?
we automatically detect patterns AND because of the few ms needed to create this but partly an illusion BUT as a result pattern recognition might make people believe things are wrong
How can we get differing experiences?
we pay attention to different things in a different state/mindset
Define biased perception
perceptual info is used to create knowledge used to interpret the world so perception/knowledge is not perfect but we still use this biased knowledge to interpret reality.
What are the conclusions?
■ Cognitive psychology uses scientific methods to create theories explaining human behaviour
■ Theories should be tested to be proven valid
■ Our interpretation of reality depends upon what we know
■ We can see things that do not exist!
■ We must have an objective method to develop theories of the human mind
■ Cognitive psychology provides a mechanistic approach to
explaining human behaviour
