Lecture 9.1: Higher Brain Functions Flashcards
Cortical Association Areas of the Brain
- Pre-frontal lobe
- Premotor cortex
- Broca’s area
- Wernicke’s area
- Temporal lobe
- Somatosensory association area
- Auditory association area
- Visual association area
The pefrontal cortex accounts for …% of total cortex in humans
29
Role of the Prefrontal Cortex
- Learning, memory & planning
- Personality (appreciation of self in the world that
allows actions to be planned and executed)
What is the Parietal Lobe involved in?
Attention and perceptual awareness
What is the Temporal Lobe involved in?
Recognition and identification of complex stimuli
What happens if the Temporal Lobe is damaged?
- Difficulty recognising, identifying and naming objects
= Agnosias - Acknowledge the stimulus but cannot say what it is
- Can describe face but not recognise the person =
damage to inferior RIGHT temporal cortex =
prosopagnosia - LEFT inferior temporal cortex damage: poor recall of
verbal and visual content (e.g music recognition)
What is Lateralisation of Function?
Tendency for some neural functions/cognitive processes to be specialised to one side of the brain
Functions of Left Brain (4)
- Processes logical tasks/analytical
- Language: spoken/heard, written/read,
gestured/seen - Maths
- Motor Skills (handedness)
Functions of Right Brain (5)
- Processes non-verbal tasks/spatial relationships
mental imagery - Emotion of Language
- Music/Art
- Visuospatial
- Body Awareness
What is Aphasias?
Disruption in the comprehension and/or generation of language
Role of Wernicke’s Area
Interpretation of written and spoken words
Language comprehension
Role of Broca’s Area
Formulation of language components and sends information to motor cortex Motor function
What connects the Broca’s and Wernicke’s Areas?
Arcuate fasciculus as subcortical white matter tracts
What happens in Wernicke’s Aphasia?
- Receptive/sensory
- Language expression is normal but comprehension
and repetition impaired - Language produced but it lacks meaning and
contains paraphrasic errors and neologisms - Written language similarly incoherent
- Unable to follow spoken or written commands
- Usually unaware and hence unaffected
What happens in Broca’s Aphasia?
- Expressive, non-fluent
- Paucity of spontaneous speech, telegraphic and
minimal - Can follow instructions as long as no need to
verbalise ‘close your eyes’ - Patient typically aware and frustrated by it
What part of the brain is damaged in Conductive Aphasia?
Arcuate fasciculus
What happens in Conductive Aphasia?
Repetition impaired but comprehension and expression intact
What happens in Global Aphasia?
Combines features of Broca’s and Wernicke’s
What is the Role of the Right hemisphere in speech?
- Adds ‘colour’ to speech
- Tone, stress, rhythm
What is Dysarthria?
Inability to correctly use muscles to verbalise
What is the Limbic System?
Complex set of cortical structures that deal with emotions, memory and arousal
Where is the Limbic System found?
Found either side of the thalamus, underneath the cerebrum
What parts of the brain are part of the Limbic System? (5)
- Hypothalamus
- Hippocampus
- Amygdala
- Cingulate gyrus – wraps around the corpus callosum
- Para hippocampal gyrus – medial temporal lobe
Roles of the Hypothalamus (4)
- Homeostasis
- ANS
- Endocrine
- Hunger
Roles of the Hippocampus (3)
- Short Term Memory
- Emotion
- Spatial Navigation
Roles of the Amygdala (3)
- Emotions
- Fear
- Aggression
Role of the Limbic System
- High level processing of sensory information and
output to homeostasis planning of behaviours and
motor responses - Attaches a behavioural significance and response to
a stimulus
What is Memory?
Ability to register (encode), store and retrieve information
Damage to what parts of the brain can cause memory issues? (2)
Impaired by diffuse cerebral injury or temporal lobe disease
Types of Memory (6)
a) Motor and non-motor
b) Declarative and nondeclarative
c) Working – current, problem solving
d) Explicit – events and factual knowledge
e) Working memory – material maintained in
consciousness
f) Long-term memory – stored unconsciously
Declarative vs Non-Declarative Memory
- Declarative memory allows us to consciously
recollect events and facts - Non-Declarative memory, in contrast, is accessed
without consciousness or implicitly through
performance rather than recollection
What is Working Memory?
- Ability to hold something in the mind for seconds to
minutes - Limited capacity (7 items) to store items/chunks of
information in conscious memory before it rapidly
disappears when attention diverted
What is Long Term Memory?
Storage of potentially unlimited capacity
What parts of the Brain are involved in Long Term Memory? (5)
- Hippocampus
- Amygdala
- Mammillary Bodies
- Thalamus
- Prefrontal Cortex
What are the 2 subsections of Long Term Memory?
- Explicit
- Implicit
What is Explicit Long Term Memory?
- Memories that are accessible to consciousness
- Episodic – autobiographical content
- Semantic – facts
What is Implicit Long Term Memory?
- Memories not consciously accessible (typically
motor memory) - Motor skills – riding a bike
- Conditioning – Pavlovian responses
- Priming – name a city
What is Amnesia?
Inability to learn new information or to retrieve information already acquired
Why is forgetting is essential?
‘Buffers’ useless information from our brains to avoid
overcrowding/distractions
What is Anterograde Amnesia?
- A type of memory loss that occurs when you can’t
form new memories - Temporal lobe dependent
What is Retrograde Amnesia?
- Amnesia where you can’t recall memories that were
formed before the event that caused the amnesia - It usually affects recently stored past memories, not
memories from years ago - More diverse throughout cerebral cortex
What is Transient Global Amnesia?
A temporary, anterograde amnesia with an acute onset that usually occurs in middle-aged and older individuals, patient’s usually wake and don’t recall the preceding 24-48hrs
What can cause Transient Global Amnesia? (5)
- Idiopathic
- Minor Head Trauma
- Sexual Intercourse
- Heavy Exercise
- Brief Shock
Which hemisphere of the Parietal Lobe is more dominant?
Right
What is Korsakoff Syndrome?
A memory disorder that results from vitamin B1 deficiency and is associated with alcoholism
