module 4 Flashcards
Left hemisphere
Language/speech
Right hemisphere
- Tone of voice/prosody
- Face perception
Perceptual grouping
- Face perception
brocas area
a patient who was unable to speak after damage to the left frontal lobe (Broca’s area)
Contralateral function: vision
- Each side of visual space mapped to contralateral visual cortex (opposite side of body)
- Left side of vision to right hemisphere
Right side of vision to left hemisphere
- Left side of vision to right hemisphere
corpus callosum
- Connects the left and right hemispheres
- Axons of neurons (nerve fibres) crossing to the opposite (contralateral) hemisphere
- Neurons send their axons via the corpus callosum to connect with neurons in the opposite hemisphere
- Allows transfer of information between the two hemispheres
hippocampus
- medial temporal lobe
- memory
- spatial navigation
memory and H.M
H.M had his hippocampus removed. causes sever memory loss. could not form new memorys or recall anything after surgery. Could remember things before. could learn new skills but not remember them.
declarative long-term memory
conscious recollection (things you can declare)
episodic memory
emory of past events or “episodes” things you’ve seen and done, e.g. what you had for lunch yesterday, what you did on your birthday last year
semantic memory
facts and basic knowledge you can recall and declare e.g. Paris is the capital city of France
procedural memory
not for conscious recall, skills you learnt e.g. how to ride a bike, how to sign your name
encoding
laying down new memories for long-term storage
Bottom-up processes
driven by external stimuli or unconscious states
Top-down processes
cognitive control or volitional choice: modulation by prior knowledge and experience
Parietal lobe
- Posterior to the central sulcus
- Attention: directing attention (eye-movements) to explore visual world
Spatial neglect (parietal lobe damage)
- Attention: directing attention (eye-movements) to explore visual world
Spatial awareness
- Linking vision to action
- Represents spatial location of objects around us for guiding actins
(map reading and mathematics ability)
- Represents spatial location of objects around us for guiding actins
Attention
- “select” and prioritise stimuli based on location or features (whatever is relevant for goal)
- Moving “spotlight” (location)
Relevant features (colour, shape, etc.)
- Moving “spotlight” (location)
Conscious controlled - top down
- Selecting and prioritising according to task or goal
- Voluntary shifting visual attention (spotlight) to search
- Choosing features for selection, or “focus of attention”
Automatic attention - bottom- up
- Attention “captured” involuntarily by highly salient stimuli
- Things that “stand out” or pop-out
Advertisers know how to capture your intention involuntarily, draw your eyes to particular things
- Things that “stand out” or pop-out
spatial neglect
eficit in directing attention to one side of space ( side contralateral to brain lesion)
- “ignore things on one side: unable to perceive stimuli on side contralateral to brain lesion
- Not due to any sensory deficit (i.e. normal vision)
simultagnosia
can’t perceive multiple object simultaneously
executive functions:
- Reasoning, planning, problem-solving
- Inhibitory control
Working memory
- Inhibitory control
Executive and inhibitory control
ucial for control of behaviour
- Selection of appropriate actions
- Inhibition or suppression of inappropriate actions or usual responses (task-switching)
disorders associated with impaired inhibitory control:
- Attention deficit hyperactivity disorder (ADHD): impulsive behaviours, difficulty preventing distraction to maintain attention on task
- Obsessive compulsive disorder (OCD): repetitive compulsive behaviour (washing, cleaning and checking)
Fronto-temporal dementia
- Degeneration (loss of neurons) in the frontal and temporal lobes
- 2nd most common dementia (after Alzheimer’s disease)
Early symptoms difficult to distinguish from Alzheimer’s disease
- 2nd most common dementia (after Alzheimer’s disease)
Disinhibition
increasingly inappropriate actions e.g. impulsive behaviour, overeating, overly-sexual behaviour, lack of social “tact”. Lack of care for appearance and personal hygiene
apathy
ack of motivation, emotional distant, withdrawn (may appear like depression)
loss of empathy
unaware of the emotions of others, lacking social skills, may become socially withdrawn
