Hand Function 7-24 Month Period

Original Editor - Robin Tacchetti based on the course by Pam Versfeld
Top Contributors - Robin Tacchetti, Jess Bell, Tarina van der Stockt, Kim Jackson, Ewa Jaraczewska and Jorge Rodríguez Palomino

Intro

. The authors observed that between 9- and 19-months of age, infants showed increasing evidence of planning ahead of the action they were actually performing

Being able to transport the hand to the mouth or more generally, contact a stimulus on the face, is only one element of the reaching act. Successful reaching to a stimulus, whether it is located on the body or in external space, typically involves the coordination of at least two different action systems: reaching and grasping (Jeannerod, 1996). Effective reaching requires individuals not only to extend their hands to the location of a stimulus, but open and orient the hand to prepare to grasp the stimulus. Developmentally, research indicates that the reaching system comes online before the grasping system (Piaget, 1952;

Development of Hand Function

Development of hand function for infants occurs in two processes; cascades in development and perception-action loops with embedded exploration and selection.

Cascades in Development

Hand development in infancy is formed by previous learned skills. New skills are a combination of established development with new skill acquistion. Hand function begins by spontaneous movement transitioning into intentional goal-directed play.

Perception-Action Loops with Embedded Exploration and Selection

Infants will use repeated trials to learn new skills. With each opportunity they learn how to vary their movement to attain success. Some patterns of movements will be fruitful than others. Performing an action repetitively allows for different sensory feedback as a consequence of their movement. This process of executing various movement patterns over repetitive trials refers to the perception-action loop.

Perception

The way in which we gather information about the events within the environment (the physical structure and the events occuring) is referred to as perception. We attain this information through an active process of the brain recognising patterns from the steady flow of sensory information. Some of the ways in which we perceive sensory information is through tasting, feeling, looking and listening. The use of hands provides the sensory function of feeling to learn about properties of the object.

7-12 Month Period

The purposes of the hand during this period is trifold:

1. As part of the postural and locomotor systems
   • learning to balance in sitting, crawling and buttock shuffling, cruising
2. For communication and in social interactions
3. For picking up, moving and manipulating objects
   • to explore their different properties and what can be done with them

Hand-Object Actions

During the 7-12 month time period, infants will use their hands to interact with objects with the varied complex actions:

• shaking
• banging
• patting, poking, stroking, flapping with the fingers
• turning objects over
• passing from one hand to the other
• throwing and dropping objects
• picking up, moving and dropping small and large objects

** By 12 months, infants reach and grasping motion are similar to that of an adult

Grasp Patterns

itting. This change frees up the upper extremities, resulting in improvements with reaching efficiency, and the child progresses from a reflexive palmar grasp, to a radial palmar grasp, and on to a pincer grasp. These advances in fine motor skills allow infants to interact with their environment, manipulate objects, self-feed finger foods, and play with simple toysAt 7 to 8 months, infants begin to voluntarily release objects from their hands, starting with an awkward and uncoordinated release and developing into a purposeful and accurate release. At 8 to 9 months, infants begin to show increased visual regard and accuracy of reach and grasp of small objects, fostering their ability to integrate visual and tactile information using both senses simultaneously. At approximately 12 months, infants use their visual system to recognize the physical properties of objects and act accordingly. Additionally, at this age, infants primarily use fingering and hand-to-hand manipulation during object exploration

As the infants learn to manipulate objects with the above hand-object actions, they also learn which grasp is best suited for each object. Repetitive trials allows them to find a finger pattern that is best suited to the size and shape of different objects.

Grasp patterns commonly seen during this period:

• Hook grasp
• Power grasp
• Palmar grasp,
• Circular grasp
• Chuck grasp
• Key grasp    

Ball Activities

The use of a ball play in infancy creates a variety of experience about how balls function. Infants learn to visually track moving balls as well as predict where the ball will stop. Anticipating the future location of a moving ball is an important skill for learning to catch a ball. Ball play with partners allows the infants to discover different ways balls move, how to catch and throw and to observe their partners actions.

Small Objects

Around 10-11 months, infants begin to poke and pick up small objects. Poking entails using an extended foreginger while picking up involves bending and extending the fingers using a raking action. As time progresses, infants will transition to a pincer or key grip to pick up small objects.

Social interaction and communication gestures

During the 7-12 month period, infants use their hands to communicate and for social interaction. Some of the various gestures you might see during this time are listed below:

• waving
• arm pointing
• clapping hands
• raising hands for hooray
• high five
• copying actions

12-24 Months

At approximately 15 to 18 months, toddlers have improved spatial relations and visual perceptual skills that contribute to an improved ability to manipulate objects in hand (e.g., single-handed management of food, toys). This improvement contributes to the development of bilateral hand use (e.g., self-feeding, toys, simple clothing

Task Structure

During the 12-24 month stage, toddlers use their hands in a more goal-directed action. They will explore objects manipulating and moving it comparing it other objects. Goal-oriented tasks requires an understanding of the series of actions needed to complete the task otherwise known as task structure. Three main components needed to complete a task structure are listed below:

1. visual information gathered for planning movements
2. predict and adapt posture in response to limb movements
3. complete a sequence of movements

Toddlers learn to perform tasks with greater accuracy over time and through repeated experiences. During play activities, toddlers will adapt their grip, their body position and the pulling force applied through their arms to accommodate for the specific task. They quickly learn how to plan, execute and adapt their movements to attain their goal.

Posting Activities

Posting or inserting refers to an activity where the toddler places objects through small openings. Often times, posting activities include small balls, rods or flat disks inserted into holes in the lids of a container. Through the undertaking, toddlers learn the size and shape of objects that can fit through the various holes.

Duration of Play

Toddlers age 12-24 months, have brief sustained periods of focused attention to a task before moving onto another activity. These quick bursts of focused play are not a sign of poor attention span but one of using the most effective way to learn about properties and affordances of many different objects. A study by Herzberg et al.2022 showed that toddlers object interactions were on (average 9.8 seconds) and varied, with transitions among dozens of toys and non-tpys.

Resources

https://babynavigator.com/resources/

https://babynavigator.com/wp-content/uploads/2021/04/Milestones-that-Matter-Mo