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Attention and Executive Function

Clinical Assessment and Intervention

College of Occupational Therapy

Specialist Section Neurological Practice

National Conference 9-10 September 2010

Charlie Chung

Content of Workshop

Part 1: Theory

►Overview of cognition

►What is attention?

►What are executive functions?

►Working memory

Content of Workshop

Part 2: Assessment considerations

►The use of screens and standardised assessment batteries.

►The use of functional assessments.

►Assessing the patient with severe attention difficulties using informal methods.

Content of Workshop

Part 3: Intervention

►Process, strategy and functional training.

►The impact of cognitive loading.

►Examples of interventions (research and video).

►Case studies (practical exercise).

►Summary.

Theory

Part 1

The Cognitive Hierarchy

Executive Function

Working Memory

Memory

Attention

WHAT IS ATTENTION?

“Attention is a cognitive brain mechanism that enables one to process relevant inputs, thoughts or actions...” (Gazzaniga 2002)p.247

Some attentional concepts:

►Covert attention: the ability to direct attention without adjusting external sensory devices.

► Activity 1: Keeping gaze directed at one point and attending to other objects in the room.

►Activity 2: Attending to each read statement without moving your head.

Some attentional concepts:

►Voluntary (endogenous) attention: the ability to intentionally attend to something.

►Reflexive (exogenous) or automatic attention: where something catches our attention.

►Inhibition of return: recent location becomes inhibited to reflexive attention.

►Activity 3: Examples of voluntary and reflexive attention.

WHAT IS SELECTIVE ATTENTION?

“Attention is a cognitive brain mechanism that enables one to process relevant inputs, thoughts or actions while ignoring irrelevant or distracting ones” (Gazzaniga 2002)p.247

Disengagement Function of Temporal-Parietal Junction

1) Disengagement of attention from its current focus.

2) Movement or shifting of attention to a new location or object.

3) Engagement of attention on the new location or object to facilitate perceptual processing of the stimuli.

Three Stage Model of Attention (Posner et al 1984)

Directing Attention

The pulvinar nucleus appears to be responsible for directing attention and does this through connections with the dorso-lateral prefrontal cortex and posterior parietal cortex.

Attentional Circuits:►Alerting network: establishes a vigilant state and

readiness to act (right frontal lobe, superior region of Brodmann area 6).

►Orienting network: orients to sensory, particularly visual signals (extrastriate regions, fusiform gyrus).

► Executive control network: control of goal directed behaviour, target detection, error detection, conflict resolution and inhibition (anterior cingulate, supplementary motor area and parts of the basal ganglia).

(Posner and Petersen 1990)

Clinical Implications► Attention work should not be limited to observable

functions, but should include internal thoughts and mental processes.

► If a patient’s gaze does not follow an instructed location, covert attention may still be possible.

► If working on directing attention, sharp auditory or visual stimuli may be eliciting reflexive attention rather than the intended voluntary attention, and in turn, may facilitate inhibition.

► It may be valuable to work on patients’ disengagement as movement and engagement of attention may be limited without being able to disengage.

► Attention work may draw upon executive function.

Executive Function

“..a set of skills or processes required for effective problem-solving, planning and organisation, self-monitoring, initiation, error correction and behavioural regulation.” (Evans 2003) p.53

WORKING MEMORY

Transient representations of task-relevant information

Working Memory Activity

Answer the previous question after the current question.

Working Memory

Central Executive

Phonological Loop

Visual-Spatial

Sketchpad

(Baddeley and Hitch 1974)

Prefrontal Cortex

Goal-Oriented Behaviour

►Goal planning

►Task control

►Attention monitoring

►Supervisory Attentional System (SAS)

Goals as a hierarchyIndependently

complete morning shower and

dressing

Step in and out of the shower

independently

Dress upper body independently

Orient shirt in preparation for

donning

Retrieve shirt from side locker

independently

Independently fasten buttons

Independently place affected arm into shirt sleeve

Independently sequence washing and dressing tasks

A series of sub goals is important to inform specific task selection.

Model of Response Selection

Shallice et al (1989)

Task Selection from Supervisory Attentional System

Clinical Implications

► Executive functions are central for goal directed behaviour and it is important to determine patients’ goal awareness.

► Contention scheduling can occur spontaneously and could result in a less appropriate task selection if the SAS is impaired.

► Activities such as dressing, which were previously routine, may now represent a novel task if sensorimotor abilities have been lost. This may require strategising and inhibition of habitual responses to return to independence.

► Hospital environments and structured therapy sessions, by their nature, restrict opportunities for patients to demonstrate and practise executive functioning.

Assessment

Part 2

List of Assessments

► Abbreviated Mental Test (Hodkinson 1972)

► Addenbrooke’s Cognitive Examination (Mioshi et al 2006)

► Chessington Occupational Therapy Neurological Assessment Battery (COTNAB) (RAF Chessington Rehabilitation Unit 1986)

► Test of Everyday Attention (TEA) (Ward and Ridgeway 1994)

► Hayling and Brixton Tests (Burgess and Shallice 1997)

► Behavioural Assessment of the Dysexecutive Syndrome (BADS) (Wilson et al 1996)

► The Clock Drawing Test (Ploenes et al 1994)

► 3 Dimensional Block Construction

► Apraxia Test (van Heugten 1999)

CONSIDERATIONS

Where assessments are significantly beyond the ability of the patient, informal methods can be valuable.

Questions to be answered

► Is the task initiated without assistance?

► Does the patient sustain attention on the task without cueing?

► Are appropriate items selected from a number of options?

► Are task items sorted appropriately?

► Is the patient able to move from one task to the next without problem?

► Does the patient identify errors and act to correct them?

► Are difficulties encountered as the task becomes more complex?

► Does the patient appear to plan an approach to the task?

► Is there a self-evaluation of performance?

Informal Assessment

►Video

►Demonstration

Assessment Task

Jean is a 74 year old female admitted to the acute stroke unit with a left CVA. She presents with dense right weakness, is unable to speak and does not have a safe swallow. You see her on the second day of admission and she is sitting awake in a Delta Chair which she was transferred into by full hoist.

Please list 10 things you can do to assess Jean’s attention and/or executive function.

Assessment Task (10 possible actions)

1. Check comprehension by giving a simple verbal command, e.g. “close your eyes.”

2. Use non-verbal commands if required, e.g. Indicate patient’s hand and therapist’s hand to touch.

3. Check reading ability using large print and instruct the patient to indicate which address belongs to her.

4. Use a simple jigsaw, e.g. Six pieces, remove one piece and give the patient an opportunity to place the one piece into the space to check visual and spatial attention.

5. Draw a noughts and crosses game on paper, make the first move and hand the pen to the patient to await a response. If able to respond, look for evidence of strategy formation.

Assessment Task (10 possible actions)

6. Provide 10 balls to be dropped into a bucket. Start by handing one ball at a time to the patient’s unaffected hand and allow him to drop it in. Place the container of balls into the patient’s lap and check iifattention can be sustained on this task.

7. Throw a soft ball into the patient’s arms to determine a catch response then wait to see if an attempt is made to return the ball. This will provide the opportunity to observe response selection.

8. Use two pictures, place them vertically in front of the patient and instruct selection of one of them, e.g. “take the telephone”.

9. Set up two containers and put a red block in one and a blue block in the other. Instruct the patient to sort a remaining group of blocks into the red and blue containers to observe for directing of attention.

10. Set out a number of numeric playing cards with one queen. Instruct the patient to find the queen.

FUNCTIONAL ASSESSMENT

Provide opportunities for the patient to initiate the task, plan, locate required items, organise the materials and sequence, identify and correct errors, and reflect on performance.

Intervention

Part 3

Intervention

Assessment findings

Goals

Intervention

Goal Level

Greater Number of Task Components

Moderate Number of Task Components

Few

Level of Independence

Goals with a greater number of task components can be set for patients with a higher level of independence

Very Few Task Components

►Will sustain attention on verbal number task for 30 seconds – 1 week

►Will independently find 5 playing cards laid out in a row on the overbed table – 1 week

Moderate Number of Task Components

►Will plan a trip to the High Street using local bus time tables with minimum cognitive assistance – 1 week

►Will independently prepare tea and toast in the occupational therapy kitchen – 2 weeks

Greater Number of Task Components

►Will demonstrate independent meal preparation – 2 weeks

►Will dress self independently including choosing and retrieving clothing – 1week

►Will take the bus to travel to the day centre – 2 weeks

►Will independently buy the weekly groceries at Asda – 2 weeks

Intervention categories

►Process activities (Sohlberg and Mateer 1987)

►Functional activities

►Strategies

Intervention Research: Attention

► Computerised training of non-specific attention (Ponsford and Kinsella 1988) (Sohlberg and Mateer 1987)(Gray and Robertson 1989) varied from multiple baseline single case studies to matched controls investigating reaction time, vigilance, selectivity and working memory tasks. Outcome: Some limited effects on working memory but others had no effect.

► Specific attention studies (Wood and Fussey 1987)(Sturm et al 1997) on sustained attention found some improvement on specifically targeted measures but no generalisation.

► Studies investigating internal strategies for improving sustained attention have shown promise (Wilson and Robertson 1992)(Robertson et al 1997)(Manly et al 2002) with the goal of bringing attention under voluntary control.

Intervention Research: Initiation

► Prompts and alerts for initiation.

► Song lyrics and music (Gervin 1991).

► Graded self instructional method (Cicerone and Wood 1987).

► Work based initiation checklist (Burke et al 1991).

► Electronic devices.

Intervention Research: Disinhibition

► Response-cost approaches.

► Self monitoring (Alderman et al 1995).

Intervention Research: Problem solving

► Breaking down a multi-stage problem (Von Cramon and Mathes-von Cramon 1991).

► Making specific procedures routine to reduce load on SAS. (Crepeau et al 1995).

► Goal management training (Levine et al 2000).

Intervention Research: Self-awareness

► Self rating scales of anticipated and experienced difficulty.

► Video-feedback (Tham and Tegner 1997)

Intervention Task

Jack is a forty six year old photographer who was admitted

to a rehabilitation unit from the acute stroke unit with a right CVA. He presents with spatial neglect, left visual field loss and a left upper limb weakness with increased tone. He can transfer between chairs with supervision.

Jack’s current goal is to put on his T shirt without assistance. He can verbalise the whole process in detail but is unable to resolve problems of the T shirt tangling and setting it up with the wrong orientation. When in difficulty, he appears to be unaware of the cause and continues regardless.

Please outline an executive function training strategy to address Jack’s problem.

Intervention Task (possible strategy)

Jack’s initial issue is a decreased awareness of how the

problems are arising and a type of awareness training is required. The use of video-feedback would enable him to view what is happening on his neglected side when he is unaware of T-shirt falling onto his forearm or getting caught on his shoulder.

Armed with this awareness, the issue of him continuing regardless requires addressing and the goal management training strategy of Levine et al (2000) could be useful as Jack has the potential to retain the stages of the approach.

The initial stage of stopping and thinking about what is happening is a crucial one for Jack.

SummaryAlthough there is little conclusive research evidence to support

attention and executive function training techniques, a number of single case studies and matched designs have investigated some potentially valuable approaches.

Three principles are evident:

1. Specific attention training appears more effective than general attention training.

2. Internal executive function approaches appear to provide the best opportunity for generalisation to other tasks.

3. The use of external strategies can be valuable for specific situations.

References

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Burgess, P. W. & Shallice, T. The Hayling and Brixton Tests. 1997. London, Thames Valley Assessment.

Burke, W. H., Zenicus, A. H., Wesolowski, M. D., & Doubleday, F. 1991, "Improving Executive Function Disorders in Brain Injured Clients", Brain Injury, vol. 5, pp. 25-28.

Cicerone, K. D. & Wood, J. C. 1987, "Planning disorder after closed head injury: a case study", Archives of Physical Medicine & Rehabilitation, vol. 68, no. 2, pp. 111-115.

Crepeau, F., DeCourcy, R., Scherzer, P., & Charette, G. "Toward a Remediation Approach to Improve Strategic Time Sharing", in Baycrest Conference on Frontal Lobe Functions 1995.

Gervin, A. P. 1991, "Music Therapy Compensatory Technique Using Song Lyrics During Dressing to Promote Independence in the Patient With Brain Injury", Music Therapy Perspectives, vol. 9, pp. 87-90.

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