Neural Basis of Cognition Flashcards
Capgras Syndrome:
• Can recognize other people, but is convinced these people are not who they appear to be (imposters)
• Facial recognition involves 2 separate systems in the brain
◦ Cognitive appraisal (I know what they look like, and I know you look like him)
◦ Emotional appraisal (You look familiar and trigger a warm response in me)
• Emotional processing disrupted (recognition without emotional response, therefore you must be someone else)
Brain and Capgras Syndrome:
- Right temporal lobe damage disrupts circuits involving the amygdala, resulting in lack of emotional response
- Right prefrontal cortex also damaged (important for planning or analysis), results in Capgras patients not being able to keep track what is real, what is sensible
Hindbrain:
• On top of spinal cord
• Important for controlling automatic functions (heart rate, breathing), balance, alertness
• Cerebellum
◦ Largest part of hindbrain
◦ Important for coordination and balance
Midbrain:
Important for coordinating movements, relating auditory information, pain perception
Forebrain:
Longitudinal fissure separates left and right cerebral hemispheres
Limbic System
Corpus Callosum
Limbic System
System of connected structures important for learning and memory
Hypothalamus
Thalamus
Thalamus
◦ Underneath cortex of forebrain
◦ Relay station for sensory information
Hypothalamus
◦ Right under thalamas
◦ Important for motivated behaviours
Corpus callosum
Thick bundles of fibers that carry info between 2 hemispheres
Neuropsychology:
• Study of brain structures and how to relate to brain function
• Clinical neuropsychology
◦ Study of function of intact, undamaged brains from case studies
Computerized Axial Tomography:
- CT scans
- Studies brain’s structure
- Uses X-rays
Positron Emission Tomography:
- PET scan
- Studies brain activity
- Involves tracking a radioactive tracer through the brain
Magnetic Resonance Imaging:
- MRI
* Uses magnetic properties of atoms in brain tissue to create pictures of brain
Functional Magnetic Resonance Imaging:
- fMRI
- Measures oxygen in content in blood flowing through each region of brain
- Can’t tell you when exactly activity took place
Electroencephalography:
- Recording of voltage changes occurring at the scalp that reflects activity in the brain underneath
- Creates electroencephalogram (EEG)
Electroencephalogram
EEGs used to study broad rhythms in brain activity
Alpha rhythm
Delta rhythm
Event related potential
an’t tell you where the activity took place precisely
Alpha rhythm
◦ Activity level rising and falling 7-10 times per second
◦ Observed when someone is awake but calm and relaxed
Delta rhythm
◦ Activity level rising and falling 1-4 times per second
◦ Observed when someone is sleeping
Event-related potential
Measure changes in EEG before, during, and after event to measure brain activity over a shorter period of time
Fusiform Face Area:
- FFA
* Part of brain that becomes active whenever a face is being perceived
Transcranial Magnetic Stimulation:
- TMS
* Strong magnetic pulse at specific location causes a temporary disruption in brain region (temporary disabled)
Primary sensory projection areas
Arrival points for signals coming into the cortex
Somatosensory area
◦ Info from skin projected to parietal lobe
◦ Stimulation results in tingling sensation
Temporal area
Stimulation results in hearing clicks, buzzes, hums
Sensory area
Visual area
Info projected to occipital lobe
Stimulation results in seeing flashes of lights or visual patterns
Sensory Area
Similarities between sensory areas
◦ Provides a map of the sensory environment
◦ Cortical space is governed by function not anatomical proportions
◦ i.e. Touch- sensitive areas get more cortical area than less sensitive areas even if they cover more area on the body
Primary motor projection areas
Departure points for signals leaving the cortex
Contralateral control
Stimulation to left hemisphere leading to movements on right side of body, and vice versa
Association Areas:
- Portion of cerebral cortex that is not motor or sensory areas
- Consists of frontal, temporal, parietal, and occipital lobes
Apraxias:
- Disruptions in ability to identify familiar objects due to lesion in parietal or occipital lobe
- Usually only affects either vision or touch (can recognize a fork by touch but not by looking)
Neglect Syndrome:
Lesion in parietal lobe that results in the individual ignoring half the visual world
Aphasia:
Lesion in areas near lateral fissure (fissure that separates frontal and temporal lobe) results in disruption in language capabilities
