What is Homo ?

 

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Homo (from Latin homō 'human') is the genus that emerged in the genus Australopithecus that encompasses the extant species Homo sapiens (modern humans), along with several extinct species classified as either ancestral to or closely related to modern humans, including Homo erectus and Homo neanderthalensis. The oldest member of Homo is Homo habilis with records of just over 2 million years ago.[a] Homo, together with the genus Paranthropus, is probably sister to Australopithecus africanus, which itself had previously split from the lineage of Pan, the chimpanzees.

Homo erectus appeared about 2 million years ago and, in several early migrations, spread throughout Africa (where it is dubbed H. ergaster) and Eurasia. It is likely that the first human species lived in a hunter-gatherer society and was able to control fire. An adaptive and successful species, H. erectus persisted for more than a million years and gradually diverged into new species by around 500,000 years ago.

Anatomically modern humans (Homo sapiens) emerged close to 300,000 to 200,000 years ago,in Africa, and H. neanderthalensis emerged around the same time in Europe and Western Asia. H. sapiens dispersed from Africa in several waves, from possibly as early as 250,000 years ago, and certainly by 130,000 years ago, the so-called Southern Dispersal beginning about 70–50,000 years ago leading to the lasting colonisation of Eurasia and Oceania by 50,000 years ago. Both in Africa and Eurasia, H. sapiens met with and interbred with archaic humans. Separate archaic (non-sapiens) human species are thought to have survived until around 40,000 years ago (Neanderthal extinction).

The Latin noun homō (genitive hominis) means "human being" or "man" in the generic sense of "human being, mankind".[d] The binomial name Homo sapiens was coined by Carl Linnaeus (1758).Names for other species of the genus were introduced beginning in the second half of the 19th century (H. neanderthalensis 1864, H. erectus 1892).

Even today, the genus Homo has not been strictly defined. Since the early human fossil record began to slowly emerge from the earth, the boundaries and definitions of the genus Homo have been poorly defined and constantly in flux. Because there was no reason to think it would ever have any additional members, Carl Linnaeus did not even bother to define Homo when he first created it for humans in the 18th century. The discovery of Neanderthal brought the first addition.

The genus Homo was given its taxonomic name to suggest that its member species can be classified as human. And, over the decades of the 20th century, fossil finds of pre-human and early human species from late Miocene and early Pliocene times produced a rich mix for debating classifications. There is continuing debate on delineating Homo from Australopithecus—or, indeed, delineating Homo from Pan. Even so, classifying the fossils of Homo coincides with evidence of: (1) competent human bipedalism in Homo habilis inherited from the earlier Australopithecus of more than four million years ago, as demonstrated by the Laetoli footprints; and (2) human tool culture having begun by 2.5 million years ago.

From the late-19th to mid-20th centuries, a number of new taxonomic names including new generic names were proposed for early human fossils; most have since been merged with Homo in recognition that Homo erectus was a single species with a large geographic spread of early migrations. Many such names are now dubbed as "synonyms" with Homo, including Pithecanthropus, Protanthropus, Sinanthropus, Cyphanthropus, Africanthropus, Telanthropus, Atlanthropus, and Tchadanthropus.

Classifying the genus Homo into species and subspecies is subject to incomplete information and remains poorly done. This has led to using common names ("Neanderthal" and "Denisovan"), even in scientific papers, to avoid trinomial names or the ambiguity of classifying groups as incertae sedis (uncertain placement)—for example, H. neanderthalensis vs. H. sapiens neanderthalensis, or H. georgicus vs. H. erectus georgicus. Some recently extinct species in the genus Homo have only recently been discovered and do not as yet have consensus binomial names (see Denisova hominin). Since the beginning of the Holocene, it is likely that Homo sapiens (anatomically modern humans) has been the only extant species of Homo.

John Edward Gray (1825) was an early advocate of classifying taxa by designating tribes and families. Wood and Richmond (2000) proposed that Hominini ("hominins") be designated as a tribe that comprised all species of early humans and pre-humans ancestral to humans back to after the chimpanzee–human last common ancestor; and that Hominina be designated a subtribe of Hominini to include only the genus Homo — that is, not including the earlier upright walking hominins of the Pliocene such as Australopithecus, Orrorin tugenensis, Ardipithecus, or Sahelanthropus. Designations alternative to Hominina existed, or were offered: Australopithecinae (Gregory & Hellman 1939) and Preanthropinae (Cela-Conde & Altaba 2002); and later, Cela-Conde and Ayala (2003) proposed that the four genera Australopithecus, Ardipithecus, Praeanthropus, and Sahelanthropus be grouped with Homo within Hominini 

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Memory and stress

Stress has a significant effect on memory formation and learning. In response to stressful situations, the brain releases hormones and neurotransmitters (ex. glucocorticoids and catecholamines) which affect memory encoding processes in the hippocampus. Behavioural research on animals shows that chronic stress produces adrenal hormones which impact the hippocampal structure in the brains of rats. An experimental study by German cognitive psychologists L. Schwabe and O. Wolf demonstrates how learning under stress also decreases memory recall in humans. In this study, 48 healthy female and male university students participated in either a stress test or a control group. Those randomly assigned to the stress test group had a hand immersed in ice cold water (the reputable SECPT or ‘Socially Evaluated Cold Pressor Test’) for up to three minutes, while being monitored and videotaped. Both the stress and control groups were then presented with 32 words to memorize. Twenty-four hours later, both groups were tested to see how many words they could remember (free recall) as well as how many they could recognize from a larger list of words (recognition performance). The results showed a clear impairment of memory performance in the stress test group, who recalled 30% fewer words than the control group. The researchers suggest that stress experienced during learning distracts people by diverting their attention during the memory encoding process.

However, memory performance can be enhanced when material is linked to the learning context, even when learning occurs under stress. A separate study by cognitive psychologists Schwabe and Wolf shows that when retention testing is done in a context similar to or congruent with the original learning task (i.e., in the same room), memory impairment and the detrimental effects of stress on learning can be attenuated. Seventy-two healthy female and male university students, randomly assigned to the SECPT stress test or to a control group, were asked to remember the locations of 15 pairs of picture cards – a computerized version of the card game "Concentration" or "Memory". The room in which the experiment took place was infused with the scent of vanilla, as odour is a strong cue for memory. Retention testing took place the following day, either in the same room with the vanilla scent again present, or in a different room without the fragrance. The memory performance of subjects who experienced stress during the object-location task decreased significantly when they were tested in an unfamiliar room without the vanilla scent (an incongruent context); however, the memory performance of stressed subjects showed no impairment when they were tested in the original room with the vanilla scent (a congruent context). All participants in the experiment, both stressed and unstressed, performed faster when the learning and retrieval contexts were similar.

This research on the effects of stress on memory may have practical implications for education, for eyewitness testimony and for psychotherapy: students may perform better when tested in their regular classroom rather than an exam room, eyewitnesses may recall details better at the scene of an event than in a courtroom, and persons suffering from post-traumatic stress may improve when helped to situate their memories of a traumatic event in an appropriate context.

Stressful life experiences may be a cause of memory loss as a person ages. Glucocorticoids that are released during stress damage neurons that are located in the hippocampal region of the brain. Therefore, the more stressful situations that someone encounters, the more susceptible they are to memory loss later on. The CA1 neurons found in the hippocampus are destroyed due to glucocorticoids decreasing the release of glucose and the reuptake of glutamate. This high level of extracellular glutamate allow calcium to enter NMDA receptors which in return kills neurons.

Techniques used to study memory

Techniques used to assess infants’ memory

Infants do not have the language ability to report on their memories and so verbal reports cannot be used to assess very young children’s memory. Throughout the years, however, researchers have adapted and developed a number of measures for assessing both infants’ recognition memory and their recall memory. Habituation and operant conditioning techniques have been used to assess infants’ recognition memory and the deferred and elicited imitation techniques have been used to assess infants’ recall memory.

• Visual paired comparison procedure (relies on habituation): infants are first presented with pairs of visual stimuli, such as two black-and-white photos of human faces, for a fixed amount of time; then, after being familiarized with the two photos, they are presented with the "familiar" photo and a new photo. The time spent looking at each photo is recorded. Looking longer at the new photo indicates that they remember the "familiar" one. Studies using this procedure have found that 5- to 6-month-olds can retain information for as long as fourteen days.
• Operant conditioning technique: infants are placed in a crib and a ribbon that is connected to a mobile overhead is tied to one of their feet. Infants notice that when they kick their foot the mobile moves – the rate of kicking increases dramatically within minutes. Studies using this technique have revealed that infants’ memory substantially improves over the first 18-months. Whereas 2- to 3-month-olds can retain an operant response (such as activating the mobile by kicking their foot) for a week, 6-month-olds can retain it for two weeks, and 18-month-olds can retain a similar operant response for as long as 13 weeks.
• Deferred imitation technique: an experimenter shows infants a unique sequence of actions (such as using a stick to push a button on a box) and then, after a delay, asks the infants to imitate the actions. Studies using deferred imitation have shown that 14-month-olds’ memories for the sequence of actions can last for as long as four months.
• Elicited imitation technique: is very similar to the deferred imitation technique; the difference is that infants are allowed to imitate the actions before the delay. Studies using the elicited imitation technique have shown that 20-month-olds can recall the action sequences twelve months later.
• Researchers use a variety of tasks to assess older children and adults' memory. Some examples are:
  • Paired associate learning - when one learns to associate one specific word with another. For example when given a word such as "safe" one must learn to say another specific word, such as "green". This is stimulus and response.
  • Free recall - during this task a subject would be asked to study a list of words and then later they will be asked to recall or write down as many words that they can remember. Earlier items are affected by retroactive interference (RI), which means the longer the list, the greater the interference, and the less likelihood that they are recalled. On the other hand, items that have been presented lastly suffer little RI, but suffer a great deal from proactive interference (PI), which means the longer the delay in recall, the more likely that the items will be lost.
  • Recognition - subjects are asked to remember a list of words or pictures, after which point they are asked to identify the previously presented words or pictures from among a list of alternatives that were not presented in the original list.
  • Detection paradigm - Individuals are shown a number of objects and color samples during a certain period of time. They are then tested on their visual ability to remember as much as they can by looking at testers and pointing out whether the testers are similar to the sample, or if any change is present.

What is interpersonal relationship ?

An interpersonal relationship is a strong, deep, or close association or acquaintance between two or more people that may range in duration from brief to enduring. This association may be based on inference, love, solidarity, regular business interactions, or some other type of social commitment. Interpersonal relationships are formed in the context of social, cultural and other influences. The context can vary from family or kinship relations, friendship, marriage, relations with associates, work, clubs, neighborhoods, and places of worship. They may be regulated by law, custom, or mutual agreement, and are the basis of social groups and societyas a whole.

what is Relationship counseling ?

Relationship counseling is the process of counseling the parties of a human relationship in an effort to recognize, and to better manage or reconcile, troublesome differences and repeating patterns of stress upon the relationship. The relationship involved may be between members of a family or a couple (see also family therapy), employees or employers in a workplace, or between a professional and a client.

Couple's therapy (or relationship therapy) is a subset of relationship therapy. It may differ from other forms of relationship counseling in various regards including its duration. Short term counseling may be between 1 to 3 sessions whereas long term couples therapy may be between 12 and 24 sessions. An exception is brief or solution focused couples therapy. In addition, counseling tends to be more 'here and now' and new coping strategies the outcome. Couples therapy is more about seemingly intractable problems with a relationship history, where emotions are the target and the agent of change.

Marriage counseling or marital therapy can refer to either or some combination of the above.

The methods may differ in other ways as well, but the differences may indicate more about the counselor/therapist's way of working than the title given to their process. Both methods also can be acquired for no charge, depending on your needs. For more information about getting the care that may be required, one should make a call to a local hospital or healthcare professional.