chapter 12 13 14 easy TF

Literacy

• Literacy is the ability to read and write, enabling communication without face-to-face contact.
• It is an expert system derived from a core set of other skills such as visual recognition, manipulation of sounds, learning, and memory.
• Visual word recognition involves processing letter strings as a whole, not one by one, and takes similar time for long and short words.
• The visual lexicon is a storage for how words are written, and the word superiority effect makes it easier to detect a letter in a word or nonsense letter string than in a random letter string.
• The visual word form area is a dedicated cognitive mechanism for visual lexicon, located in the left mid fusiform gyrus, and also responds to visual objects and Braille reading.

Acquired Reading Deficiencies

• Central dyslexia: disruption of reading arising after computation of a visual word form.
  • Surface dyslexia: reading nonwords and regularly spelled words better than irregularly spelled words.
  • Phonological dyslexia: reading real words better than nonwords.
  • Deep dyslexia: real word reading prone to semantic error.
• Peripheral dyslexia: disruption of reading arising up to the level of computation of a visual word form.
  • Pure alexia: acquired difficulty in reading words, leading to letter-by-letter reading, with reading time increasing proportionately to the length of the word.

fMRI Studies

• Multiple areas involved in literacy, predominantly left-lateralized.
• Inferior frontal lobe (Broca's area), inferior parietal lobe (Wernicke's and angular gyrus), and anterior and mid-temporal lobes (semantic memory) are involved in literacy.
• Reading uses similar brain regions across different languages, albeit to varying degrees.

Spelling and Writing

• Dysgraphia: difficulties in spelling, similar to central dyslexia.
  • Deep dysgraphia: real word spelling prone to semantic error.
• Dysgraphia is generally multimodal, with patients producing the same kinds of errors in writing, typing, or oral spelling.
• Some evidence shows separate written versus oral letter name output codes in spelling, indicating involvement of motor codes in writing.

Numeracy

• Universal numeracy is not limited to math and is present in humans and other species, enabling them to estimate quantity and perform basic calculations.
• Fundamental sense of numeracy is universal, except for dyscalculia.

Numbers

• Non-symbolic number processing is universal and allows us to perform tasks, such as subitizing (enumerating an exact quantity of objects without counting them) for 4 items and less.
• Numbers above 4 can only be processed approximately rather than exactly in the absence of language.
• When we write in Arabic digits, we symbolize numbers.

Processing Symbolic Numbers

• Distance effect: faster to decide which number is larger when the distance between two numbers is large.
• Size effect: easier to judge which of two numbers is larger when the numbers are small, compared to when they are large.

Neural Substrates

• Number meaning involves not only countable quantities but also continuous and uncountable quantities, such as length, area, and brightness.
• Restle's MNL (Mental Number Line) and Walsh's ATOM (A Theory of Magnitude) are theories of number processing.

Numbers and Space

• SNARC effect: Spatial-Numberical Association of Response Codes, where numbers are associated with spatial locations.
• Cultural SNARC and SNARC-like effects have been observed in various studies.

Triple Code Model

• Abstract (semantic) magnitude
• Verbal store of numbers and operations
• Visual representation for numerals (digits) and workbench for certain calculations

Executive Functions

• Executive functions are complex processes that optimize performance in situations requiring multiple cognitive processes, involving a meta-cognitive, supervisory, or controlling role.
• Not tied to a specific domain (memory, language, perception, etc.), but related to the prefrontal cortex.

Problem-Solving

• Problem-solving involves generating a solution to a goal, often tested with tasks like the Tower of London, FAS test, and Cognitive Estimates Test.
• Prefrontal cortex lesions can lead to poor problem-solving abilities.

Inhibition

• Inhibition involves reducing the likelihood of a particular thought or action.
• There are two types: overcoming habitual responses (e.g., Stroop task) and overcoming potent responses (e.g., Go/No-Go task).
• Related to medial PFC, specifically anterior cingulate cortex and pre-SMA.

Task Switching

• Task switching requires discarding a previous schema and establishing a new one, involving PFC activation.
• Damage to the PFC can lead to perseveration (failure to shift).
• The Wisconsin Card Sorting Test assesses task switching abilities.
• Switch cost: a slowing of response time due to discarding a previous schema and setting up a new one.

Multi-Tasking

• Multi-tasking involves carrying out several tasks in succession, requiring task switching and maintaining future goals while dealing with current goals.
• Patients with anterior prefrontal cortex lesions may be impaired at multi-tasking, despite performing well on individual tasks.
• The Six Element Test assesses multi-tasking abilities.

Decision Making

• Decisions are not solely based on rationality, and can be influenced by factors like framing or social justice perception.
• The anterior cingulate cortex (ACC) and orbitofrontal cortex (OFC) are involved in decision making.

Somatic Marker Hypothesis

• Somatic markers form the link between past experiences stored in the cortex and emotional responses stored in regions like the amygdala and insula.
• Stored in the ventromedial prefrontal cortex (vmPFC), somatic markers play a role in controlling ongoing behavior, especially in situations involving feelings.

Decision Making and Reward

• The Iowa Gambling Test assesses decision making and reward processing.
• Delay discounting involves choosing between current and future rewards, with lateral PFC involved in evaluating different rewards at two future points.

Multiple Demand Network

• The multiple demand network comprises the lateral PFC, ACC, and intraparietal sulcus, involved in cognitive control.
• Fluid vs. crystallized intelligence are related concepts.

Hemispheric Differences

• Lateralization is more pronounced in humans compared to other primates.
• Left lateral PFC is specialized for problem-solving, while right lateral PFC is involved in task monitoring.

Anterior Cingulate Cortex (ACC)

• ACC is part of the limbic system and can be functionally divided into two regions: dorsal ACC (cognitive division) and rostral ACC (affective division).
• ACC is involved in error detection and behavioral adjustment, with activity on error trials and increased activity on subsequent trials.