Task Load Index

The NASA-TLX (Task Load Index) questionnaire is a tool developed by NASA to assess the workload and subjective workload experienced by individuals performing a task. Though initially designed for pilots, it is widely used across various industries including autism research 

The questionnaire has 6 subscales/submeasures, that assess different dimensions of workload. 

• Mental Demand: mental effort and cognitive load required to perform the task.
• Physical Demand: physical effort and exertion involved in performing the task.
• Temporal Demand: perceived time pressure and the amount of time available to complete the task.
• Performance: individual's perception of their own performance during the task.
• Effort: perceived level of effort and energy expenditure required to complete the task.
• Frustration: degree of annoyance, stress, and dissatisfaction experienced during the task.

Scoring and Interpretation

Participants rate each submeasure on a scale of 0 to 100. Scoring and interpretation vary depending on the specific study or context. Generally, higher scores indicate a higher perceived workload in the respective submeasure. 

Researchers often analyze the individual submeasure scores and the overall workload score to gain insights into the specific dimensions of workload that are most significant in a given task or situation. The questionnaire can help identify areas where workload can be optimized or where additional support or resources may be required.

Examples of use in Autism Research in evaluating workload and cognitive demands 

Study: "Task load and verbal responses to questions in children with autism spectrum disorder"Citation: Nishida, T., Yuhi, T., Kaneoke, Y., Kurosawa, K., & Dan, I. (2014). Task load and verbal responses to questions in children with autism spectrum disorder. Frontiers in Human Neuroscience, 8, 937.
Link: https://doi.org/10.3389/fnhum.2014.00937

Study: "Measurement of cognitive workload in individuals with high-functioning autism spectrum disorder using a virtual reality task"Citation: Park, S. M., Chong, S. C., Lim, S. L., Kim, J. S., & Kim, J. S. (2020). Measurement of cognitive workload in individuals with high-functioning autism spectrum disorder using a virtual reality task. Applied Sciences, 10(2), 581.
Link: https://doi.org/10.3390/app10020581

 Creativity is the antidote to monotony.

- Hari Srinivasan

Simultaneity Window

[Concepts in Sensorimotor Research]

Simultaneity Window (SW) refers to a temporal window within which the brain perceives stimuli from different sensory modalities as occurring simultaneously. It represents the temporal range over which the brain integrates sensory inputs from different modalities into a coherent percept.

If stimuli from different modalities fall within the SW, they are likely to be perceptually integrated, whereas if they fall outside the SW, they may be perceived as separate events.

Commonly used research tasks to measure SW

• Temporal Order Judgment (TOJ): participants are presented with 2 stimuli, one in each sensory modality (e.g., a flash of light and a beep), and they have to determine the order in which the stimuli occurred.
• Simultaneity Judgment (SJ): Participants are presented with 2 stimuli, from different modalities, and they have to judge whether the stimuli were perceived as simultaneous or not.
• Temporal Alignment Task: Participants are presented with a stimulus in one modality and have to adjust the timing of a stimulus in the other modality until it is perceived as synchronous with the first stimulus. This helps in determining the temporal window of integration.
• Temporal Recalibration Task: Participants are exposed to a consistent asynchrony between stimuli from different modalities over a period of time. Following this exposure, their perception of simultaneity is tested to see if it has been recalibrated.

The perception of simultaneity can vary across individuals and is influenced by various factors such as attention, age, disability, the specific sensory modalities involved, and distance of stimuli (as determined by, say the PPS).

 To create is to be fully human.

- Hari Srinivasan

 Creativity is the art of making something out of nothing.

- Hari Srinivasan

EEG Capping

 

EEG capping from a neuroimaging researcher perspective at the Vanderbilt EEG research lab 

(rather than as a half sedated patient in a hospital clinic).

Felt like a soggy swim cap. Not the most comfortable feeling but tolerable.

To clarify, in this photo I'm trying on the cap to see what it feels like as I will likely be using neuroimaging methods (EEG, fMRI etc) in my own research design and I will be studying issues in autism.

 Creativity is the energy that drives progress.

- Hari Srinivasan

 Creativity is the power to inspire and transform.

- Hari Srinivasan

Summer Soltice

Sun's longest sojourn

Heat waves dance in the daylight

Melting ice cream dreams.

The summer solstice is an astronomical event that occurs annually around June 20th or 21st in the northern hemisphere and around December 21st or 22nd in the southern hemisphere. It marks the longest day and shortest night of the year.

Astronomically, the summer solstice happens when the Earth's axial tilt is most inclined towards the sun. This means that the North Pole is tilted directly towards the sun, resulting in the sun appearing at its highest position in the sky, and the rays of sunlight falling more directly on the northern hemisphere. Conversely, in the southern hemisphere, the South Pole is tilted away from the sun, leading to shorter days and longer nights.

During the summer solstice, the sun reaches its highest point in the sky at noon, and the length of daylight is at its maximum. This phenomenon occurs because the Earth's axis is tilted approximately 23.5 degrees relative to its orbit around the sun. As the Earth orbits the sun, this tilt causes the amount of sunlight received by each hemisphere to vary throughout the year, leading to the changing seasons.

Many western european cultures celebrate the summer solstice. Some examples. 

• Stonehenge, England:  People gather to witness the sunrise aligned with the ancient stone monument.
• Midsummer's Eve  in Scandinavia (countries like Sweden, Denmark, and Norway) is celebrated with bonfires, traditional dances around maypoles, and feasts. It is a significant holiday in these cultures, often associated with fertility, love, and the celebration of nature.
• Sankthans (St Johns Eve), Norway: is celebrated on June 23rd in Norway. People gather around bonfires, sing songs, and enjoy traditional food and drinks. It is a time for community bonding and merriment.
• Fête de la Musique (Music Day), France:  musicians of all genres perform in the streets, parks, and public spaces. It is a day of music appreciation and open-air concerts.

However, summer solstice festivities tend to be less common or less significant in regions closer to the equator (eg: parts of Africa, South America, and Southeast Asia). This is because the equatorial regions experience relatively consistent day lengths and sunlight throughout the year, with only minor variations so the seasons are less pronounced. As a result, the solstices do not bring about significant changes in the length of the day or the angle of the sun, as they do in regions farther from the equator. 

There are however some festivals in these regions that somewhat align and happen around the time of summer solstice. 

• The Massai of East Africa (Kenya and Tanzania): A traditional  warrior dance called Adumu (jumping dance) is performed during special occasions, including the solstices, as a way to celebrate and mark important events in their calendar.
• The Kukuya of Central Africa (Congo): have a solstice ritual called the "Iboundji" ceremony where people gather around a sacred tree and engage in traditional dances and songs to honor the sun and its role in their lives.
• The Dayak of Borneo: The  "Gawai" festival is held around June 1st coincides with the rice planting season and the beginning of the rainy season, and includes various rituals and celebrations that pay homage to the sun, earth, and spirits for a bountiful harvest.
• The T'boli of the Philippines:  During the summer solstice, people perform ceremonies and rituals related to the T'nalak art form (traditional weaving of abaca fibers into intricate patterns), which is believed to have spiritual and cosmic significance. 

 The world needs more dreamers who can turn their dreams into reality.

- Hari Srinivasan

Psychophysics and Autism

The field of psychophysics explores how humans perceive and interpret sensory information, including vision, hearing, touch, taste, and smell. It investigates how changes in physical stimuli result in changes in perception, allowing researchers to measure and quantify the relationships between physical stimuli and perceptual experiences.

Psychophysical experiments often involve participants making judgments or providing responses to stimuli under controlled conditions. These experiments use psychophysical techniques to measure and analyze perceptual thresholds, discrimination abilities, response biases, and other aspects of sensory perception.

Some common psychophysical methods and measures include:

• Threshold determination: Identifying the minimum or maximum level of a stimulus that can be detected or discriminated.
• Scaling: Estimating subjective perceptions using rating scales or magnitude estimation.
• Difference thresholds: Assessing the smallest detectable difference between two stimuli.
• Response time measures: Examining the speed of processing or decision-making in response to stimuli.

Psychophysics has contributed to our understanding of sensory perception, including concepts such as Weber's Law, Stevens' Power Law, and Fechner's Law. It has applications in various fields, such as vision science, auditory perception, psychopharmacology, and the study of human factors in design and technology.

Use of Psychophysics in  Autism Research

• Sensory processing differences at various levels, such as visual, auditory, and tactile domains. Researchers have utilized psychophysical methods to measure thresholds, discrimination abilities, and response biases related to sensory perception. This helps in identifying specific sensory sensitivities, hypo- or hyper responsiveness, and atypical processing patterns in individuals with autism
• Perceptual integration and binding of perceptual features, such as color, motion, or shape, in autistics. By examining how autistics perceive and integrate different sensory information, researchers gain insights into potential difficulties in integrating and perceiving coherent perceptual representations.
• Face and emotion perception studies investigate perceptual thresholds, discrimination abilities, and biases related to facial features, expressions, and emotional cues. They can provide insights into the specific challenges  in perceiving and interpreting social cues.
• Multisensory processing: Psychophysics has been utilized to explore how autistics integrate information from multiple sensory modalities. By measuring sensory integration and cross-modal processing abilities, researchers gain a better understanding of how individuals combine information from different sensory channels, which can contribute to their overall perceptual experiences.

 Creativity is the spark that ignites change.

- Hari Srinivasan

Looking at the Self

In the context of disability and autism, all the terms discussed below takes on a unique significance as individuals may grapple with challenges that affect their physical, cognitive, emotional, and social attributes. Understanding one's own abilities, limitations, and unique traits can be an integral part of developing a positive self-perception and fostering self-acceptance and empowerment within the disability and autism communities.

Self-Perception: refers to how we perceive themselves, including our physical, cognitive, emotional, and social attributes. It involves forming an understanding of one's own characteristics, abilities, and behaviors. Self-perception can encompass both internal aspects, such as thoughts and emotions, and external aspects, such as appearance and social roles. It involves recognizing oneself as a distinct entity separate from others and the environment.

Self-Reflection: involves the process of introspection and examining one's thoughts, feelings, and experiences. It entails looking inwardly and exploring one's own inner world. Self-reflection allows individuals to gain insight into their beliefs, values, motivations, and behaviors. It often involves asking oneself questions, considering personal experiences, and analyzing one's own actions and their consequences. Self-reflection facilitates self-understanding, personal growth, and the ability to learn from past experiences.

Self-Evaluation: refers to the process of assessing one's own abilities, performance, and worth. It involves comparing oneself to internal or external standards and making judgments about one's strengths, weaknesses, and accomplishments. Self-evaluation can be influenced by various factors, including personal goals, social comparisons, and feedback from others. It plays a crucial role in shaping self-esteem, as positive self-evaluation can enhance feelings of self-worth and competence, while negative self-evaluation can lead to self-doubt and low self-esteem.

Self-Awareness: is the conscious knowledge and recognition of one's own existence, thoughts, feelings, and sensations. It involves being cognitively and emotionally attuned to oneself. Self-awareness allows individuals to monitor and reflect upon their own internal states, behaviors, and reactions in relation to themselves and their environment. It involves recognizing one's own strengths, weaknesses, values, and beliefs. Self-awareness is a fundamental aspect of self-consciousness and is essential for introspection, self-regulation, and social interactions.