Assisted Decision-Making:A medical perspective DR.SELEMANI S.

Transcription

1 Assisted Decision-Making:A medical perspective DR.SELEMANI S.

2 Cognitive Function Definition:mental process of knowing and becoming aware,function closely associated with judgement Information-Processing Memory Thought,language and cognition Social Cognition Discourse and Narrative Medical and Neuropsychiatric conditions

3 Useful Concepts:Mind & Brain Mind:Emanates from a portion of the activity of the brain Human experiences of sensation,thought,emotion,attention,self reflection and memory Brain:composed of about 100 billion neurons.an average neuron is connected to +/-10 thousand other neurons at synaptic junctions Neural net profile is the fundamental way in which mental processes are created

4 Mind & Brain Activation of neurons can lead to further neural processes that produce a range of internal events and external behaviors The essential components of the mind come directly from how these neural events create the flow of energy and information Energy is contained within the activation of neural circuits Information is contained within the patterns of activation termed neural net profile or mental representation

5 Information Processing These representations serve as symbols that cause further effects in the mind leading to the processing of information A symbol carries information about another object in the world. Examples of representational forms include perceptual,sensory,linguistic and more abstact representations of concepts and categories

6 Information Processing(1) Within the cognitive function,these information-processing events can be seen as the contrasting,comparing,genera lizing,chunking,clustering,differentiating and extracting processes that lead to a more highly interwoven set of mental representations

7 Memory A:Energy lead to Neural response B:Input lead to Mental representation leading to Effect C:Input triggers (1)Sensory Memory that activates working memory whose output is expressed in behavior or mental representational process D:Input triggers sensory that impacts on working memory.the information is transferred to Longterm memory(permanent memory)

8 Memory(1) Within the working memory:representation can be consciously manipulated,contrasted,clustered and reassembled Thus,consciousness may be intimately related to this aspect of mental functioning Cognitive processes group bits of information into large chunks

9 Memory(2) Attention:process that controls the flow of information processing.it involves 3 compo nents:(1)selectivity,(2)capacity,(3)sustained concentration Selectivity has 3 dimensions:(1)filtering, focusing on specific attributes,(2)categorizing,based on stimulus class,(3)pigeonholing,reducing perceptual information needed into a specific category(schizophrenia)

10 Memory Systems Neurons which fire together,wire together Implicit or nondeclarative memory:in place after the first years of life and remains active throughout the lifespan.implicit memory involves a wide range of systems including behavioral,emotional and perceptual memory When these circuits are activated in retrieval,they do not have the sensation of something being recalled

11 Memory systems(1) Explicit or Declarative Memory:involves the conscious sensation of something being recalled at the time of retrieval and allows for the awareness of the autobio- graphical or factual knowledge to be shared The Explicit memory requires the involvement of focal attention and the activation of the hippocampus for encoding and retrieval. Episodic/semantic or declarative memory is expressed in words or drawing

12 Memory Systems(3) The existence of intact implicit recollection in the absence of explicit memory is found in various conditions:(1)surgical anesthesia,(2)hypnotic amnesia,(3)adverse effects of some benzodiazepines,(4)korsakoff s syndrome,(5)post-traumatic Stress Disorder

13 Consciousness The vast majority of mental processes are outside of conscious awareness.these processes can impact thinking,feeling and behavior despite lack of awareness Consciousness includes 2 elements: (1)awareness and(2) sentience,the quality of experience One essential issue is that the effective processing of mental representaions does not require conscious awareness

14 Consciousness(1) However,the intentional,strategic alteration in patterns of processing may necessitate the involvement in order to achieve a new outcome Conscious awareness is a specialized aspect of some cognitive processes

15 Thought,Language & Cognition Thinking involves the mental representa- tion of some aspect of the world or of the self and the manipulation of these representations Thinking depends on explicit memory and implicit memory for prior experiences Thought processes can be influenced by a person s emotional state and mental models Basic components of thinking:categorization, judgement,decision making and general problem solving

16 Thought,Language&Cognition(1) The ability to judge the probability of uncertain events is a fundamental aspect of the rationality of thought The lack of conformity of thinking to the rules of logic is one aspect of disordered thought processing Thinking is important in choice(decision to choose among various options)

17 Thought,Language&Cognition(3) Each of these processes contributes to the goal of problem solving:data are assessed classified,transformed and compared on the basis of logical rules to produce a choice that solves a problem Failures in these steps can result in limitations and distortions in normal thought processes. The earlier mode of thought(narrative cognition is present by age 2,later mode:scientific,logical, paradigmatic

18 Social Cognition The domains include:empathy,interpersonal communication,person perception,relationship scripts and group processes Social Cognition uses informationprocessing theory to asssess the compo nents of attention,perception,encoding, memory,retrieval and schemata

19 Discourse & Narrative Discourse is thought to involve a sense of intention or plan Normal discourse follows a set of rules that ensure the coherence and effectiveness of communication:what is intended to be stated by the sender is understood by the receiver(listener) Incoherent discourse is the hallmark of some psychiatric conditions

20 Discourse & Narrative Narrative:way in which a person creates a verbal account of a sequence of events and the internal subjective experience of the characters of the story Narrative helps to record and make sense of the past,interpret the present and anticipate the future

21 Medical & Neuropsychiatric Disorders Cognitive Development:(1)arrested patterns of normal cognition:mental Retardation,(2)deviant developmental pathways:autistic Disorder,(3)specific cognitive impairments schizophrenia Cognitive Disorders:Delirium,Dementia, Amnestic disorder

22 Illustrative Case:Dementia Development of multiple cognitive deficits manifested by:(1)memory impairment(ina bility to learn new information&to recall previously learned information,(2)at least one of the following cognitive disturbances :aphasia,apraxia,agnosia,disturbance in executive functions:abstraction,sequencing,planning,problem solving

23 Dementia:clinical stages Mild Stage:MMSE 21-26: 1.Cognition:(1)recall/learning,(2)word finding (3)problem solving,(4)judgement,(5)calculation 2.Function:(1)work,(2)money/shopping,(3)cooking, housekeeping,(4)reading,(5)writing, (6)hobbies 3.Behavior:(1)apathy,(2)withdrawal,(3)depression (4)irritability

24 Dementia:clinical stages(1) Moderate stage:mmse: Cognition:(1)recent memory,(2)language: names,paraphasias,(3)insight,(4)orientation (5)visuospatial ability 2.Function:(1)IADL loss,(2)misplacing object (3)getting lost,(4)difficulty dressing:sequence,selection 3.Behavior:delusions,depression,wandering,insom nia,agitation,social skills unaffected

25 Dementia:clinical stages(2) Severe:MMSE:<10 1.Cognition:attention,difficulty performing familiar activities,language 2.Function:basic ADLs:dressing,grooming, bathing,eating,continence 3.Behavior:agitation,delusions

26 Clinical Dementia Rating Memory Orientation Judgement and problem solving Community affairs Home and hobbies Personal care Scoring:0:healthy,0.5:questionnable,1:mild 2:moderate,3:severe

27 Conclusion Cognitive function is the key to any sound informed decision making Information-processing is the pivotal factor in cognitive function Different degrees of impairment can be encountered in daily practice Taking into account the complexity of the mind,the ability to understand or retain information as well as the aptitude to make informed,rational decision are the cornestone of our practical approach to incapacity