Somatosensory System Flashcards
Sensory information arising from receptors that are distributed across wide areas of the body, primarily tactile and prop
Somatosensory, Will affect what is happening in the entire body
A collection of several systems that provides info about the body
Somatosensory system
Three main functions of __________ include Prop, exteroception, and interoception
Somatosensation
One function of somatosensation which allows us to sense our own body, involving sensations from muscles, joints, tendons and skin
Proprioception
Why do we include “skin” as one of the sources of sensation (under prop) when discussing somatosensation?
Add skin in prop because in order to figure out that you have something very small in your hand, you close your small joints and stretch skin over joints, which tells you how far you bend that joint. Also stretching skin over the joint
T/F: Deep pressure and prop use the same receptors
False. Different receptors are used to interpret prop vs deep pressure
One function of somatosensation: the sense of direct interactions with the external world as it impacts on the body including touch, heat, cold and pain
Exteroception
Where are the receptors for prop located?
Receptors located in the joints and ligaments
T/F: In tx, we want the client to use prop via passive movement e.g., joint compressions
False. We want client to perform active movement with resistance. If you move someone’s arm or do joint compressions, prop receptors will act, but not active. If have kid weight bare on hands on table, adding prop b/c not something he normally does
Function of somatosensation; sense of the functions and state of internal body organs
Interoception.
T/F: A child with low tone often has decreased interoception
True. With low tone, affects the info they’re receiving. Often has bowel, GI problems
Perception of information from touch receptors in the skin; includes pressure (static and dynamic), vibration, localization of touch, point discrimination, stereognosis
Tactile Perception
Perception of body and limb position
Proprioception
A special category of proprioception; a perception of body and limb positions during movement, sometimes defined as conscious awareness of body and limb position
Kinesthesia. Receptors are the same, but processed in diff. parts of CNS and carried through different pathways
The following is not a function of tactile perception and proprioception (somatosensation)? A. Physical Safety B. Connection with the social world C. Development of body scheme and praxis D. Motor Learning E. Development of motor skills F. Refinement of movement G. Language development H. Influence on state regulation (arousal & activation)
G. Language development
How does tactile perception and prop aid in a connection with the social world for infants?
Through touch newborns are calmed down
T/F: children have more tactile receptors throughout their limbs than their mouth
False. They have more receptors in the oral area
Why do children often put items in or around their mouth?
- They have more receptors in the oral area.
- They may also be seeking prop, but must look at force with which one is putting objects in mouth. If just moving around lightly, seeking touch. But if clenching jaw, seeking prop.
- However, exploring with mouth is normal behavior
Why is tactile perception important as a child explores his environment?
Children do everything through touch e.g., putting objects in/around mouth
T/F: When we observe a child moving, we are seeing motor planning, whereas we cannot see body scheme
True. Body scheme is intermediate process between senses and praxis (motor planning)
T/F: Children with decreased tactile discrimination often have increased motor planning
False. Children with decreased tactile discrimination often have decreased motor planning–well studied in SI.
If you are treating a child with autism and motor planning problems, how do we find out if this is related to poor SI (tactile discrimination specifically) in a clinical setting?
- Give light touch and see if the child reacts to input–if he is underresponsive or responds only once in a while, will have a tactile discrimination problem
- If he cries, he is overresponsive–not linked to motor planning
T/F: Exteroception is critical, although not often assessed in the field of SI
False. Interoception is critical, although not often assessed in the field of SI. May be related to bowel or bladder control among children with SI problems.
T/F: Chemoreceptors monitor and contribute to regulation of organ functions (e.g., blood gasses and pH) while mechanoreceptors detect pressure (e.g., gastric, bowel, and bladder distention)
True. Part of interoception
What is the first sensory system to mature in utero and the most mature system at birth?
The tactile system: Phylogenetically old system for gathering info from the environment
T/F: We are conscious of tactile sensations most of the time
False. We are NOT conscious of tactile sensations most of the time
General Tactile System Functions include all except which of the following:
A. Emotional bonding: contact comfort
B. Emotion and arousal regulation
C. Detection and perception of objects and materials that contact skin
D. Evokes protective as well as exploratory action
E. Contributes to development of body scheme and praxis
F. Associated with gross motor coordination
F. associated with FINE motor, not gross motor coordination. Important role in object manipulation, such as tool use. With decreased tactile discrimination, feel like you have glove on–influences fine motor
What are qualitative vs. quantitative aspects of tactile stimuli?
- Qualitative: nature of stimulus; WHAT is it? What are its properties? WHERE is it?
- Quantitative: intensity of stimulus; HOW intense?
- Qual, Quant, and affective are affected in children with problems
Aspects of tactile stimuli that refer to the amount of pleasure or displeasure that one experiences
Affective aspects. Most perceptions don’t have affective rxns. Children with problems may put emotional quality on stimuli that doesn’t have emotional aspect with it. Overresponsiveness is related to the emotional responses and qualities you give to something. BUT need to look at environment–what else is going on when you see affective quality–could be there is too much going on around
Many reflexes are elicited by _______ input at birth
Many reflexes are elicited by tactile input at birth e.g., rooting, sucking, grasp
One of the first means of environmental interactions is elicited via this system
Tactile System. Emotional and sensorimotor interactions with the environment. It is one of the first ways a child interacts with the outside world
Why is it important to look at systems that develop early on e.g., tactile system?
Need to look at systems that develop early b/c they impact how the CNS develops. B/c tactile develops early, many reflexives we test early on are tactile
T/F: Hand to mouth motor pattern occurs only after birth
False. Occurs very early in utero and within 6 hours after birth
How may overresponsiveness to touch affect an infant’s predictable developmental sequence of tactual exploration?
If child is developing typically, explores body with hands and puts hands to knees, hands to toes, and developing abdominal. If he has an overresponsiveness to touch while exploring, not going to have same pleasure that would normally have, so will stop doing. So, if he stops exercising, will have decreased abdominal work. In tx, often see hanging abdomin and decreased flexion. If stop doing, will affect motor development
T/F: Emergence of tactile recognition memory for objects occurs by 5 years of age
False. occurs within 1 year of age.
T/F: Sucking-swallowing, rooting, foot grasp, stepping, and hand grasp are all early sensory reflexes
True
T/F: Results of the stereognosis determine the presence of a tactile discrimination problem
False. Need to assess in many different ways:
-Does he localize? Steoreognosis?
T/F: According to data from the SIPT, by the age of 4-5, a child has the ability to accurately identify the location of a single tactile stimulus similar to adult ability. Stereognosis occurs around the same time.
False. Stereognosis is more complex, and continues to develop through childhood
In multiple studies, Ayres found significant associations between scores on _______________ tests and motor planning tests.
In multiple studies, Ayres found significant associations between scores on tactile perception tests and motor planning tests. This led her to theorize that tactile perception is an important contributor to the development of praxis
In the groundbreaking studies of Harry Harlow, infant monkeys preferred a cuddly surrogate mother without food, not a wire mother with food. What did these studies show?
“Contact-comfort” is critical to social-emotional development
- Importance of early SI
- With children with sensory issues, going to be deprived of sensations not b/c of parental enrichment, but because nervous system deprives of sensory experiences.
- Monkeys’ experiences stayed with them for life
- Mary Schreider did similar studies using alcohol
Studies show that rats and monkeys raised in isolation experienced increased anxiety, heightened emotional reactivity to stressful events, and impaired learning. This shows that _________ is critical in infancy
Nurturing tactile contact with caregiver is critical in infancy. Mice separated from their mothers show long-term changes in behavior and brain development. Early caregiver neglect may change the way the brain is wired.
T/F: We sometimes see children from an environment that is not rich in different types of sensory experience. We can then assume that these sensory deprivations are due to developmental issues that we see.
False. Need to be able to differentiate if problems are due to secondary issues related to the environment or if a child is born with them
What kind of interventions had positive physiological effects on infants?
Gentle tactile interventions.
- Rats separated from mother have student growth; human simulation of maternal stroking led to production of growth hormone and catch-up of physical growth
- Human premature infants benefit from tactile interventions in NICU: physiologically (weight, respiration); behaviorally (improved state regulation, attentiveness, decreased crying)
T/F: As OTs, we can implement tactile stimulation via massage therapy to make behavioral/developmental changes for the long run.
False. Results from massage are temporary (not what we do). We work on tactile related to movement–active. We need to incorporate touch in tx while kid is moving.
Research on effects of touch therapy for healthy preterm infants (Tiffany Field and colleagues) displayed which of the following improvements in infants?
A. Facilitates weight gain in preterm infants
B. Reduces stress hormones
C. Alleviates depressive symptoms
D. Reduces pain
E. Improves immune function
F. Alters EEG in the direction of heightened awareness
G. Reduces length of hospitalization
H. A and C
I. All of the above
I. All of the above.
Note: We need to incorporate touch into tx while kid is moving–active
T/F: Touch effects brain development
True. Brain scans of infant rodents who were deprived of physical contact with their mothers appear different from those who had physical contact
Human children deprived of what kind of input present in the following ways:
- Have significant developmental delays
- Often present autistic-like behaviors, which emerge at about 6 months of age
- Very often have severe sensory modulation problems, usually involving the tactile system
Human children deprived of a nurturing caregiver. These findings suggest that nurturance, including touch, enables the infant to have a normally developing system emotionally
The DCML tract is responsible for ________ touch
The DCML tract is related to discriminative touch, touch pressure, and proprioceptive info. Related to problems with tactile discrimination.
Where does discrimination occur in the brain?
Discrimination (DCML tract) occurs at the primary sensory cortex–travels from thalamus
The STT tract is responsible for what kind of touch responses?
STT:
- Pain, temp, diffuse (spread over wide area) touch
- Affective touch, sexual communication
- Role in social communication, emotional responses
- Related to problems with tactile overresponsiveness/defensiveness
Where does tactile defensiveness occur in the brain?
Tactile defensiveness (STT) occurs at the reticular formation
T/F: The DCML tract is responsible for tactile overresponsiveness/defensiveness, whereas the STT tract is responsible for tactile discrimination
False. The DCML tract is responsible for tactile discrimination, and the STT tract is responsible for tactile overresponsiveness/defensiveness (affective touch)
