Psychology: Attention and Sensation

 

(ITP-09) Attention and Sensation

Attention

Attention is the cognitive process of selectively focusing on specific aspects of our environment while ignoring others. It is an essential aspect of human perception and plays a crucial role in our ability to learn, remember, and make decisions.

Types of attention: voluntary and involuntary.

• ·         Voluntary attention involves a conscious effort to focus on a particular stimulus or   task.
• ·          Involuntary attention is automatic and reflexive.

Attention is a limited resource, and our ability to sustain it over time can decline if we are exposed to prolonged or distracting stimuli. Attention can also be affected by factors such as fatigue, stress, and mood.

Senses by Sensation Process: Vision, Audition, Smell, Taste, and Touch

As a psychology student, it is important to understand how our senses work and how they are processed by our brain. In this blog, we will be discussing the five senses: vision, audition, smell, taste, and touch. We will explore how these senses work and the sensation process that occurs when we experience them.

1. Vision

Vision is the sense that allows us to see the world around us. It is a complex process that involves the eyes, brain, and nervous system. The sensation process of vision begins when light enters the eye through the cornea, a clear layer at the front of the eye. The light then passes through the pupil, a small opening in the center of the iris. The iris adjusts the size of the pupil to control the amount of light that enters the eye.

2. Audition

Audition is the sense of hearing, which allows us to perceive sound. Sound waves entering the outer ear and ear canal start auditioning. Eardrums vibrate with sound. The three middle-ear ossicles boost these vibrations. Amplified sound waves trigger inner ear cochlear hair cells. Hair cells provide auditory nerve signals to the brain from sound waves. The brain produces sounds from these signals.

3.    Smell

Smell is the sense that allows us to perceive odors. The sensation process of smell begins when odor molecules enter the nose and bind to receptors in specialized tissue in the nasal cavity. These receptors then send signals to the brain through the olfactory nerve. The brain then processes these signals and creates the sensations of smell.

4. Taste

Taste is the sense that allows us to perceive flavors. The sensation process of taste begins when taste buds on the tongue and in the mouth detect chemicals in food and beverages. These chemicals then bind to receptors on the taste buds, which send signals to the brain through the facial, glossopharyngeal, and vagus nerves. The brain then processes these signals and creates the sensations of taste.

5. Touch

Touch is the sense that allows us to perceive pressure, temperature, and pain. The sensation process of touch begins when sensory receptors in the skin detect stimuli such as pressure, temperature, or pain. These receptors then send signals to the brain. The brain then processes these signals and creates the sensations of touch.

While each sense works independently, they also work together to give us a more comprehensive experience of the world. For example, the taste of food can be influenced by its aroma (smell) and texture (touch), and the perception of a sound can be influenced by the direction it came from (vision).

Factors affecting sensations:

1. Age: As we age, our sensory abilities may decline. For instance, our vision and hearing may become less acute, and our sense of taste and smell may become less sensitive.
2. Genetics: There are genetic differences in how individuals perceive and process sensory information. For example, some people may have a heightened ability to detect certain tastes or smells.
3. Environment: Our surroundings can also affect our sensations. For example, background noise can make it more difficult to hear sounds, and strong odors can mask other smells.
4. Attention: Our level of attention can also affect our sensations. For instance, if we are focused on a particular sound, we may be less likely to notice other sounds in the environment.
5. Expectations: Our expectations can also influence our sensations. For example, if we are told that a particular food is spicy, we may perceive it as being hotter than it actually is.

 

Thresholds in Sensory Perception: Lower, Upper and Differential Threshold (JND)  

Sensory perception is the process of detecting and interpreting stimuli in our environment. These thresholds vary depending on the type of stimulus and the individual's sensory abilities. There are three main types of thresholds: Differential, lower, and upper.

1.    Lower Threshold

The lower threshold is the minimum amount of stimulation required for a person to detect a stimulus. For example, the lower threshold for taste might refer to the minimum amount of a particular substance required for a person to detect a specific taste, such as saltiness. The lower threshold can be affected by various factors such as age, genetics, and environmental factors.

2.    Upper Threshold

The upper threshold is the maximum amount of stimulation that can be perceived before it becomes overwhelming or painful. For example, the upper threshold for touch might refer to the maximum amount of pressure that can be applied before it becomes painful.

3.    Differential Threshold (JND)

The Differential threshold, also known as the just noticeable difference (JND), is the smallest difference in stimulation between two sensory inputs that can be detected at time. For example, if you were to listen to two tones of slightly different frequencies, the difference threshold would be the minimum frequency difference required for you to detect a change in pitch.

References:

1. Bell, A. H., & Buchner, A. (2012). Perceptual learning in sensory substitution. Neuroscience & Biobehavioral Reviews, 36(10), 2202-2213. https://doi.org/10.1016/j.neubiorev.2012.08.004
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Cognitive Psychology: Information coding in visual cells

(CP-06) Information coding in visual cells

Abstract: The process of information coding in visual cells is a fundamental topic in Cognitive Psychology, providing insights into how the brain processes visual information and how we perceive the world. The process begins with sensation and vision, where sensory receptors in the eyes receive and interpret visual stimuli. The photoreceptors in the retina translate visual information into neural signals that are then sent to the brain via the optic nerve. Factors that impact information coding include illumination, spatial frequency of visual stimuli, color vision, and top-down processing. The eye plays a vital role in the process, with structures like the cornea, lens, and retina responsible for receiving and focusing light onto the photoreceptors. Understanding information coding in visual cells provides a better understanding of cognitive processes like attention, perception, and memory.

Introduction: One of the most important topics in Cognitive Psychology is information coding in visual cells. This topic is important because it helps us understand how the brain processes visual information and how we perceive the world around us. In this blog, we will discuss the process of sensation, vision, and the role of the eye in information coding.

Sensation: Sensation is the process of receiving information through the senses. The process of sensation starts with the reception of stimuli by sensory receptors. The sensory receptors are specialized cells that are located in the sense organs. For example, the eyes contain sensory receptors called photoreceptors, which are responsible for the reception of visual stimuli.

Vision: Vision is the process of interpreting visual information received by the eyes. The process of vision starts with the reception of light by the photoreceptors in the retina. The retina is the layer of tissue at the back of the eye that contains the photoreceptors. There are two types of photoreceptors: rods and cones. Rods are responsible for low-light vision, while cones are responsible for color vision.

Information coding in visual cells: The process of information coding in visual cells is the process by which the visual information is translated into neural signals that can be interpreted by the brain.

The photoreceptors in the retina are responsible for this process. When light hits the photoreceptors, it triggers a chemical reaction that causes a change in the membrane potential of the photoreceptor. This change in the membrane potential leads to the generation of an action potential, which is a neural signal that can be transmitted to the brain.

The photoreceptors are arranged in such a way that they form a pattern in the retina. This pattern is called the receptive field of the photoreceptor. The receptive field is the area of the retina that is sensitive to a particular visual stimulus. When a visual stimulus is presented in the receptive field of a photoreceptor, it triggers an action potential in that photoreceptor.

Optic nerve: The information from the photoreceptors is then transmitted to the brain via the optic nerve. The optic nerve is a bundle of nerve fibers that carries the neural signals from the retina to the brain. The neural signals are then interpreted by the brain to form a visual image.

Role of the eye: The eye plays a crucial role in the process of information coding in visual cells. The eye is responsible for the reception of visual stimuli, which is the first step in the process of vision. The eye contains several structures that are important for this process, including the cornea, the lens, and the retina.

The cornea is the transparent outer layer of the eye that helps to focus light onto the retina. The lens is a flexible structure located behind the iris that helps to further focus the light onto the retina. The retina contains the photoreceptors that are responsible for the reception of visual stimuli.

Factors affecting the process of information coding:

There are several factors that affect the process of information coding in visual cells. One of these factors is the level of illumination. Photoreceptors are more sensitive to light when the level of illumination is low. This is why we have better night vision in low light conditions.

Another factor that affects information coding in visual cells is the spatial frequency of the visual stimulus. The spatial frequency refers to the number of cycles per degree of visual angle in a visual stimulus.

·         Visual stimuli with high spatial frequency (i.e., fine details) are coded by the retina, which contains a high density of cones.

·         Visual stimuli with low spatial frequency (i.e., coarse details) are coded by the peripheral region of the retina, which contains a higher density of rods.

Color vision is also an important aspect of information coding in visual cells. Cones are responsible for color vision, and there are three types of cones that are sensitive to different wavelengths of light (i.e., red, green, and blue). The combination of these cones allows us to perceive a wide range of colors.

The process of information coding in visual cells is also influenced by top-down processing. Top-down processing refers to the use of prior knowledge and expectations to interpret sensory information. For example, if we expect to see a particular object, our brain may use this expectation to influence the interpretation of the visual information.

In conclusion, the process of information coding in visual cells is a complex and dynamic process that is influenced by several factors. By understanding this process, Cognitive Psychology students can gain a deeper understanding of how we perceive the world around us and how the brain processes visual information. Information coding in visual cells is a fascinating topic that has significant implications for our understanding of cognitive processes such as perception, attention, and memory. Through continued research in this area, we can gain a deeper understanding of how the brain processes visual information and how we perceive the world around us.

References:

1. Alilovic, J., & Brkanovic, M. (2019). Top-down processing in visual perception: An overview. International Journal of Psychophysiology, 137, 1-8. https://doi.org/10.1016/j.ijpsycho.2018.11.007
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7. Kastner, S., & Ungerleider, L. G. (2000). Mechanisms of visual attention in the human cortex. Annual Review of Neuroscience, 23(1), 315-341. https://doi.org/10.1146/annurev.neuro.23.1.315
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Cognitive Psychology: Organization of brain and cognitive function

 

(CP-04) Organization of brain and cognitive function

Abstract: This article discusses the organization of the brain and its cognitive functions, which is essential for psychology students. The human brain is divided into three main parts: the forebrain, midbrain, and hindbrain, each responsible for specific cognitive functions such as sensation, perception, emotion, motivation, and memory. The forebrain is the largest and most complex part and includes the cerebral cortex, limbic system, basal ganglia, and thalamus. The midbrain is responsible for vision, hearing, movement, and arousal, while the hindbrain regulates physiological functions necessary for survival, including heart rate, blood pressure, and respiration, as well as sensory processing, movement, and coordination of movement and balance. These areas work together to maintain overall health and well-being, and also play a role in cognitive functions such as learning and memory.

Top of Form

Introduction: As a psychology student, it is essential to understand the organization of the brain and its cognitive functions. The brain is one of the most complex organs in the human body, and it is responsible for many cognitive functions that are essential to our everyday life. In this blog post, we will discuss the organization of the brain and the cognitive functions that take place in its different parts. In this blog post, we will discuss the organization of the brain and the cognitive functions that take place in its different parts.

Organization of the Brain:

The human brain is divided into three main parts: the forebrain, the midbrain, and the hindbrain.

The forebrain is the largest and most complex part of the brain. It is divided into several areas, each of which is responsible for specific cognitive functions. Here are some of the main areas of the forebrain and the cognitive functions that take place in these areas:

1. Cerebral cortex: The cerebral cortex is the outermost layer of the forebrain and is responsible for many cognitive functions, including sensation, perception, movement, reasoning, and language. The cortex is divided into four lobes, each of which is associated with specific functions.

a. Frontal lobe: The frontal lobe is located in the front of the brain and is responsible for cognitive functions such as problem-solving, decision-making, and planning.

b. Parietal lobe: The parietal lobe is located in the top and back of the brain and is responsible for processing sensory information from the body. It is also involved in spatial awareness and attention.

c. Temporal lobe: The temporal lobe is located on the side of the brain and is responsible for processing auditory information and memory.

d. Occipital lobe: The occipital lobe is located in the back of the brain and is responsible for processing visual information.

2. Limbic system: The limbic system is a group of structures located in the center of the brain that is involved in emotional processing, motivation, and memory.

a. Amygdala: The amygdala is responsible for processing emotional information and generating appropriate emotional responses.

b. Hippocampus: The hippocampus is involved in the formation and retrieval of memories.

c. Hypothalamus: The hypothalamus is responsible for regulating bodily functions such as hunger, thirst, and temperature.

3. Basal ganglia: The basal ganglia are a group of structures located deep within the forebrain that are involved in motor control, learning, and reward processing.
4. Thalamus: The thalamus is located in the center of the forebrain and is responsible for relaying sensory and motor information to the cortex.

 

The midbrain:

The midbrain, also known as the mesencephalon, is a small but important part of the brainstem. It is located between the forebrain and hindbrain and is responsible for several important functions, including vision, hearing, and movement. The tectum is responsible for processing visual and auditory information, while the tegmentum is responsible for motor control, pain perception, and arousal.

Here are some of the main areas of the midbrain and the cognitive functions that take place in these areas:

1. Tectum: The tectum is the dorsal (upper) part of the midbrain and is responsible for processing visual and auditory information.

2. Tegmentum: The tegmentum is the ventral (lower) part of the midbrain and is responsible for several important functions, including motor control, pain perception, and arousal.

In addition to these areas, the midbrain is also involved in several important reflexes, including the pupillary light reflex, which controls the size of the pupil in response to changes in light, and the startle reflex, which is involved in the response to sudden stimuli.

The hindbrain:

The hindbrain is the lower part of the brainstem, which is responsible for many basic physiological functions necessary for survival.

1. Medulla oblongata: The medulla oblongata is located at the base of the brainstem and is responsible for several important functions, including regulation of heart rate, blood pressure, and respiration.

2. Pons: The pons is located above the medulla oblongata and is involved in several functions, including sensory processing, movement, and sleep.

3. Cerebellum: The cerebellum is located at the back of the brain and is involved in the coordination of movement and balance.

In addition to these areas, the hindbrain is also involved in several important reflexes, including the gag reflex and the swallow reflex.

The hindbrain is a critical part of the brainstem that is responsible for several basic physiological functions necessary for survival. The medulla oblongata is responsible for regulating heart rate, blood pressure, and respiration, while the pons is involved in sensory processing, movement, and sleep. The cerebellum is responsible for the coordination of movement and balance and may also play a role in cognitive functions. These areas work together to help us navigate the world and maintain our overall health and well-being.

Conclusion:

In conclusion, as a psychology student, it is important to understand the organization of the brain and its cognitive functions. The brain is responsible for many essential cognitive functions, including sensory processing, perception, memory, emotion, conscious thought, and language. Understanding the different parts of the brain and their cognitive functions can help us better understand the complexities of human behavior and the workings of the mind.

References:

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