Категории: Все - rehabilitation - modeling - cognitive - lesions

по Joerg Bauer 11 лет назад

681

Cognitive Neuropsychology

Cognitive neuropsychology has evolved significantly through modern technological advancements like fMRI, providing a deeper understanding of brain functions and representations. It has shifted from merely localizing functions to more complex modeling approaches, which is crucial for applications such as guiding surgeries.

Cognitive Neuropsychology

Cognitive Neuropsychology

Success of CNP

But problems with central systems (problem solving)
Treatment / rehab of amnesics (JS)
Models of face recognition vs. emotinal express
Colthearts Model of dyslexia by testing lesioned brains (surface dyslexia= damage to lexical route)
vs Developemental dysl: difficulties learning

Cognitive Modelling: If lesioned do react the same?

Goals of CNP

Create / Support models
How to build models

Infer normal funcions from damaged systems

Double Dissotiation (different subsystems?)

Problems with Double Dissot.

damaged connnectionist models (single system) behaves like doulbe dissoti.

Could the patient use a compensatory strategy?(not really function on one task)

Normal functioning

not both below normal: otherwise perhaps one impaird function

What is normal performance?

How much degradation is impairment

differnt stimuli (tests) might lead to errors

Living / non living in two labs

It is therefore important to ensure that a patient is tested in a variety of ways to ensure that seemingly normal performance is being produced in a normal fashion

Why

Single disotiations: A but not B: --> A harder B?

Amisics loose A declarative but have B procedural

Where

Blindsight

Double Dis. in one Pateint: Differnt deficits blindsight vs. of intact vision

Memory

Amnesia

HM has deficient LTM but intact STM

KF has defective STM but intact LTM

Speech

Broca / Wernecke

Recognition

Face Reogniton vs. Emotional Expression Recogntion

Face Regocnition

Prosopagnosia

Not recognizing familiar persons

Capgras Delusion

Looks like wife but is imposter

Agnosia: (Object recog)

Goodale

Patient DFDorsal/ Ventral

Implicit OK: grasping diretion or hand size

Explicit No! Could not recognize even simple shapes

Humphreys & Riddoch: Recog. happening in stages

JF: semantics clear but cannot name

maybe more diffiuclt not different subsystems

single dissotiations

HJA: object: percept - doesn't look familiar

Split Brain

Ramachandran: Higher order lang. mean. trasf. cortically

Left analytical, right emotional

Sperry & Gazzaniga: Patients Left brain saw nothing: language / Right Spatial can draw object

Is model consistent with behaviour?

Data from other patients
Former:Localization of Function: Now Understanding Processes
Providing Treatments /How
Helping amnesics

HMs mirror drwaing improved (implicit learing)

Neuropage: implicitly learn to check the messenger to be reminded of...

Train procedural memory (JC ran own business)

Understanding lesions deficits
Assessment of deficit/What

Comp. data from other patients

Normal -Cog. Metods

Coltheart: Model IAC Modil based on errors shown by dyslexics

Memory tasks: Amnesics show recency effect/ not primacy

Standardised Tests

Birmingham Object Recognition

Wechsler Intelligence

Wechsler Memory

Brain Imaging:

Images: Determine the level of when sth. is coloured

Problem: Images will not show the "how"

Damasio: difficulity in recognition: tools (a glove: "appears to have 5 outpoutchings ...") / animals/ people: reduction in brain areas

Subtopic

Inteviews

Localization/where

Methods

Post Mortem brain examination (TAN)

Wisconsin Card Sorting Task: -sort cards to constanly new rules--> Difficulty =Frontal lobes?

Neuroimaging

Validity of CNP

Problems with group
Same symptoms but other behavioural differenes might be overlooked
Are individuals (lesions) comparable?
Problems with single case
Select a single patient because he confirms theory
Abilities vary over time? (test different times)
No correlations possilbe (size of area and ability)
Hard to find double dissotiatian in one case
Is he representative

Split brains may develop different

General Problems
We have comparable brains - no should be no martian among us
deep dislexia brain may not form normally/ genetic issues
Single case enough - there should be no martian
Subtractivity: The brain is modular

Functions can move

Brain is plastic and can repair

Patients develope compensatory strategies

Fodor says only for input and output - not i.e. problem solving

Similiar damage=similiar deficits

But brains and lesions differ

Deficits are because of lesion

There might have been deficits before

Modern Cog. Neuropsychology

Relevance Today through Technical Developements: fMRI
Away from localizatino to modeling(like diagramm makers)
Important to guide Surgery (destroy language center)
Only input and output seems localized/ not higher functions
Provided Language of representatinos and processes

History

Concept of localisation
Localizationists

Wernecke:

Wernickes Area: Imp. for storing sound patterns (phonemes)

Pationent could speak but not understand speech

Paul Broca:

Brocas Area: Imp. for coordinating speech musculature

Patient: TAN TAN TAN: unterstand but not speak

CASE of Phineas Gage

Harlow (1868): Disrupted G. ability to plan and maintain acceptable behaviour

Iron shot through frontal lobes altered social skills

Noted patterns of behaviour related to certain lesions

diagramm (process) makers: Lichteim

Case of phineas gage

Fell out of favour

Inconsistencies with localization

Beavourism: we cannot know what is going on

modelling cog. processes

Phrenologists

Brain is Modular: Processes have locations: Fundamental for CNP

Identifying those locations important objective

Abilities localized in the brain

Gall: Bumps /shape of skull hint to character