[W5] - CH10 Flashcards
Why do SNP evaluations assess sensorimotor functions@
The inclusion of the assessment of sensory-perceptual and motor functions is unique to an SNP evaluation compared to a psychoeducational evaluation.
In the integrated SNP model sensory motor functions serve as a prerequisite
baseline for all of the higher order processes.
School neuropsychologist should routinely investigate whether higher order
processing deficits are caused by underlying deficits in sensorimotor problems.
Define Sensory processing disorder
Umbrella term for a variety of neurological
disabilities that interfere with the normal ability to use sensory information to function
smoothly in daily life.
Dysfunction in any one sensory system can have a dramatic effect on a child’s
learning capabilities and behavioral regulation.
Define Sensory Functions
Our ability to process visual, auditory, kinesthetic, and olfactory
information.
Types of Sensory Dysfunctions: Overstimulated vs. Understimulated
Overstimulated: Sensory input my be painful (e.g., hypersensitivity to touch)
Understimulated: Does not respond to pain or injury (sensation seekers)
How do sensory-motor integration problems manifest?
Difficulties with balance, movement, using
both sides of the body in a unified fashion, confusion over right vs left sided
movements.
The role of the primary visual cortex in sensory functions
Primary visual cortex:
- Regulates sense of sight
- Located in the striate cortex of the Occipital Lobe
- Retina in the back of the eye transmits info via the optic nerve
- Optic nerve splits in 2 before reaching higher cortical regions of the brain [Temporal (lateral) part continues to higher cortical regions on the same side of the body / Nasal (medial) part continues to higher cortical regions by
crossing to the opposite side of body at the optic chiasm] - Both parts stop in the lateral geniculate nuclei or the pulvinar nucleus of the
thalamus and the superior colliculus of the midbrain - Final pathway for visual info is from lateral geniculate nuclei to primary visual
area of the occipital lobe
The role of the primary auditory cortex in sensory functions
Primary Auditory Cortex:
- Regulates sense of hearing
- Located in the superior part of the Temporal Lobe and buried within the sylvian
fissure. - Cochlea is auditory sense organ in the ear
- Projections from cochlea pass through the subcortical relays of the medial
geniculate of the thalamus, then onto the supratemporal cortex.
The role of the primary somatosensory cortex in sensory functions
Primary Somatosensory Cortex:
- Regulates sense of touch, pain, temperature sense, and limb proprioception
(limb position). - Located in the Postcentral Gyrus.
Two pathways for information:
- Anterolateral system- Pain and temperature sense.
- Dorsal column-medial lemniscal system- Touch, proprioception and
movement.
The role of the primary olafactory cortex in sensory functions
Primary Olafactory Cortex:
- Regulates sense of smell
- Located in the ventral region of the anterior temporal lobe
- Secondary area is in the lateral parts of the orbitofrontal cortex
- It is the only sense not processed by the thalamus, pathways go directly to the cortex.
Contralateral vs. Lateral Projections for the Senses
Vision, hearing and touch have contralateral projections:
- Someone with a deficit in a right sided sense organ will show as
damage in the left side of the brain that controls that sense organ
Sense of smell doesn’t have a contralateral projection:
- A lesion in the right ventral region of the temporal lobe will
produce a severe deficit when an odor is smelled in the right nostril.
Define Achromatopsia; Ageusia; Anosmia; Asterognosia; Autopagnosia; Graphestheia; Hemianopia; Hypesthesia; Kinesthesia; Pallinopsia; Parosmia; Proprioception; Tactile defensiveness; Two-point discrimination disorder.
Achromatopsia: A rare disorder in which color is not recognized.
Ageusia. Loss of the sense of taste.
Anosmia. Impaired sense of smell.
Asterognosia. Inability to recognize an object on the basis of its three-dimensionality through palpation (a.k.a., tactile agnosia/dysnosia).
Autotopagnosia. Disturbed body scheme that manifests itself by the inability to
identify the parts of one’s body.
Graphestheia. Difficulty recognizing shapes or letters written on the hand.
Hemianopia. A loss of vision for one-half of the visual field of either one or both eyes.
Hypesthesia. Diminished capacity for physical sensation.
Kinesthesia. The conscious awareness of joint position and body
movement in space.
Pallinopsia. Visual perseveration of a stimulus no longer present.
Parosmia. An abnormal sense of smell.
Proprioception. The unconscious awareness of sensations coming from one’s
muscles and joints that helps regulate our position in three-dimensional space.
Tactile defensiveness. The tendency to react negatively to unexpected,
light touches.
Two-point discrimination disorder. The inability to discriminate between
sensations arising from a single touch versus two simultaneous and
nearby touches
A brief summary on DCD
- Exhibit substantially below expected levels of motor coordination compared to
same aged peers and measured cognitive abilities (clumsy/awkward) - Marked impairment in the development of motor coordination
(i.e., delays in reaching developmental motor milestones (crawling, walking,
sitting))
Have difficulty mastering gross motor tasks (catching a ball, jumping) and fine motor tasks (Tying shoelaces, buttoning a shirt)
Often have developmental delays in expressive and receptive language (in
isolation or combined) or in phonological processing - and frequently comorbid with ADHD, conduct disorder and pervasive developmental
disorder.
Prevalence as high as 6% for children aged 5-11.
Males more affected than females (ratio between 2:1 and 7:1)
At risk for secondary problems in academic achievement and social-emotional
functioning.
The Neuroanatomy of Motor Functions - the premotor and primary motor cortex
The frontal regions of cortex are involved in planning movements: - Ventral Stream (what is happening - terminating in
the inferior temporal cortex)
- Dorsal Stream
(where its happening - terminating in the posterior
parietal lobe)
- Premotor cortex: Regulates preprogrammed or sequential motor responses and
involved in learning and executing complex movements. - Primary Motor Cortex: Regulates the motor movements of our body.
- Cerebellum plays an important role in motor coordination
The neuroanatomy of motor functions - pyramidal vs. extrapyramidal systems
Pyramidal and extrapyramidal system- Semi independent neural systems that help regulate motor activity in humans.
Pyramidal system:
- Executive system responsible for the Initiation of Voluntary
Skilled Movements involving rapid and precise control of the extremities.
- Composed of precentral motor cortex and corticospinal tract plus its
connections to the spinal motor neurons
[Disorders: Cerebral palsy, diplegia, paraplegia, hemiparesis,
hemiplegia]
Extrapyramidal system:
- Helps regulate Motor Coordination and maintain Posture.
- Formed by cerebellum, basal ganglia, red nucleus
and substantia nigra regions of the brainstem.
[Disorders: Choreas, dystonias, postural disruptions, tics, Tourette
syndrome]
Sensorimotor Items from the Neuropsychological Processing
Concerns Checklist for Children and Youth
(NPCC-3)
Basic Sensory Deficits:
* Difficulty with pitch discrimination (tone deaf).
* Difficulty with simple sound discrimination.
* Known or suspected hearing acuity problems.
* Difficulty identifying basic colors (color blind).
* Difficulty smelling or tasting foods
* Less sensitive to pain and changes in temperature.
* Complains of loss of sensation (e.g., numbness)
Motor Functioning Difficulties:
* Muscle weakness or paralysis.
* Muscle tightness or spasticity.
* Clumsy or awkward body movements.
* Walking or posture difficulties.
Visual-Motor Functioning Difficulties:
* Difficulties with drawing or copying.
* Difficulties with fine motor skills (e.g., using a pencil).
Neurologically-Related Sensorimotor Symptoms:
* Displays odd movements (e.g., hand flapping, toe walking).
* Displays involuntary or repetitive movements.
* Ignores one side of the page while drawing or reading.
* Difficulty with dressing (e.g., buttoning and zippering).
Sensory Sensitivity Issues:
* Does not like loud noises.
* Overly sensitive to touch, light, or noise
